Okay, here's a quick thought Morley. Since you have access to that storage area, take the closet door off, buy a super cheap door from the home improvement store, run your duct straight in through a hole in the door, then, use a second inline fan on the outside that pulls air out from another hole in the door at the top (hot air rises). That way you have an actual air return and you will get far better ventilation, and you won't destroy your landlord's door. You might also get better cooling, because you're pulling the hot air out. Just a thought, but other than that, great video, always fun watchin you solve these problems!
Yep, since the problem is venting hot humid air, put a hole in the top of the door with a pc fan. The hot humid air goes out, the cool dry air comes in the bottom, and he wouldn't need all the ducting.
There is a ceiling vent right there in the hallway too. Just print a ceiling vent cover he can attach a duct and run it through the door and set the thermostat to fan only. A small dehumidifier might help as well.
Sorry Morley, I usually love your videos but as an HVAC guy myself I found this whole operation a bit poorly thought out, it is defiantly a way to do it... but you are missing some of the key elements in any HVAC system, VENTILATION! That gap you used at the bottom of the door is there for a reason, its called an "Undercut" and allows air circulation when doors are closed. You gotta have some way of letting the pressure out or you are just stalling your blower as it try's to pressurize the room. This effectively makes you only have small percentage of the cooling potential possible not to mention the uninsulated duct not helping your fate. Just ditch the ducting, add some vent fans to the door, and replace it when you move out. Maybe keep part of the duct to spread the cool air further back in your hallway if necessary.
What about halving the size of the duct at the bottom of the door? Only the first bit of it has air flowing anyway, and then it frees up the rest of the door for ventilation.
Buy a new door and follow the HVAC man’s advice…. But also vent that printer fumes all the way outside. Maybe all you need to do is aggressively suck/ push the printer fumes out of that room, from an enclosed printer rack. Then that evacuation of the fumes will suck cold air in.
He's also got about 400 watts or more of heater in that small space. The printer heater cartridge and computer equipment. It's more likely the the ambient air changed than that cooling system is working. I hate those AC units because as they discharge air out the patio, they are bringing uncooled air in from the hallway or outside. You can't discharge air without make up air coming in from somewhere. He's be better off with a new door and a window unit through it, and a discharge fan at the patio door IMO.
If you're going to be printing and working in that same room, you really need to add a lot of active ventilation for the printers. There are a lot more VOCs and very fine particulates coming off of printers than we used to think, and they're bad for your health long term. CO2 building up in the room from your breath could also be a problem. You might want to get a meter and see how much it rises over the day with you in the room. It'll make you sleepy and less able to think. You could repurpose this whole system for that though! On days when it's not hot, connect the hose to the spot where the AC vents out the door and reverse your inline fan, and you'll be pulling out air! You would need a way for clean air to get in the room to replace the vented air.
With the constant/dropping humidity I'd expect enough air exchange inside this room. This will push out any VOCs/PM{2.5,10} of this tiny space as well. It's simply now a positive pressure chamber.
I work in a room with 6 printers and have noticed zero side effects. But I only print PLA and PETG. Resin is the most dangerous for VOCs and toxic particulates inside your lungs
@@LexxDesign3D that's the insidious thing about particulates and lung damage. You won't necessarily notice it right away. Unfortunately PLA and PETG seem to be less safe than we thought. They still generate a fair amount of VOCs and particulates, they just aren't as bad as resin. It's just one of those things where it's so simple to mitigate the risk that it's absurd to not do so.
You need to use insulated ducts, you're losing all of the effectiveness because the cool temp is being loss through the duct. If you touch your ducts they will be cold especially closest to the AC Unit. Using an inline fan will only force air, but its still losing cooling through the material of the duct. Use an insulated duct to fix this problem. Also remove half of the side of your floor baffle that isnt effective. You need a way for air to push out of the room equally as important as air being pushed in. I would buy a smaller AC unit for your office and push the hot air out through the duct system you made, and let the AC blow cold air into your studio, that would really drop the temps.
This, exactly. Plus, your support ribs for the door plenum block too much airflow, they only had a few small circles cut in them. If you measure their total area, you'd see that your available airflow area is less than 20% of what you calculated for the door gap. Shrink the door plenum to 50% width, and redesign the support ribs to be in the direction of airflow, not against them (think marble run channels), to divvy up the airflow and spread it across the gap without impeding airflow. With these changes, you'll likely double the airflow over your current solution.
Yep, very good point. It's way easier to push the hot air out of that room to atmosphere and cool it directly rather than cooling it from a distance with no way for the hot air to release
What I thought... Unfortunately I am very hard feeling pressure changes and would get headaches with this approach. Good when it is working for you...🎉
@@sydnerdNot true, there can be air in without air out. Air is a compressible fluid. Additionally, the harder it is for it to exhaust hot air, the more friction in the system, the harder it is to move the air into the room. With just that little inline fan, that translates to less are moved.
Crazy thought, but if you're not allowed to make holes, why not replace the door with your own custom (pallet/recycled wood?) door that has all the features you need? Cool video, still renter friendly
Yes, the opening for the door duct has, "sufficient" volume, but one major thing you overlooks, is the connection between the adapter and the tube. You're effectively going from an open pipe to a tiny sliver or a cylinder that then flares out. If you want greater airflow (there are other more important things that could be improved actually), it would be better to shape the adapter like a wide-nozzle vacuum attachment. It would spread the volume of air more evenly across the floor adapter before it flows out and under the door.
I'm hesitant to believe you actually think this was a good execution and result, I'm sorry... 1. In the before, your 3D-printer was running, in the after it was not. 2. There's no air return, making the whole system inefficient and you're not venting out CO2 or VOC's from the printers. 3. You made at least 30 screwholes following a pattern, not exactly the same as hanging a few pictures. 4. Painting everything white doesn't make it not ugly. I would love to see you revisit this with all the good feedback from the comments (temporary door, air return, AC inside the cupboard, CO2-monitor). Onwards and upwards!
Almost all of his videos are like this. He sells failures as sucusses. He's supposed to be an engineer but he misses crucial details that drive him to redo everything. He just doesn't seem to have any well thought out processes. He's just not cut out for the whole "inventor" thing.
@@TechnologistAtWorki was gonna say that redoing everything is very common in engineering, but i'm now more concerned about you. you've commented 15 times on this channel, all of them in an extremely negative way. why do you even watch his videos if you don't enjoy them?
@@Thomas-sg4iz His videos are suggested to me. And no that's not how prototyping works. I'm an engineer myself and prototyping is mainly improving a product but fixing fatal flaws. If you scrap your work so much and redo it from scratch then you don't know what you're doing. Look up any popular product prototypes, they're usually a gradual improvement not total failures and start over. He didn't see the airflow impedance over a long distance, he didn't see the gap variance for that door. All his videos are like that but he keeps claiming that he's an inventor. There is stuff that he makes you could easily not see them working then the results are expected by the end of the video. There's a bit of arrogance in the things he says and it's fascinating watching him fumble at the end, yet he learns nothing and always has a positive take instead of acknowledging his mistakes. Then comes you. No clue about how engineers work yet you're trying to pick an argument about it. That's just bizarre. Are you his lawyer?
@@TechnologistAtWork Reminds me of the "I like to make stuff" channel. They guy acts like he's got a plan, that the knows what he's doing, and is all, "You just do this..." - but then his videos are him backtracking a ton, restarting completely, stumbling the entire way, and in the end, he's all, "Well, this doesn't do exactly what I set out to do", or "So, this didn't actually work at all, but maybe you could pull it off with..." And it's like, guy - I just watched your twenty minute video, and you didn't actually do anything worth doing/you took the worst possible path/you could have Googled any of this before starting and it would have been so much easier and faster.
You should have used as much straight and smooth piping as possible. That would have made the airflow a lot less turbulent and it would have improved the look in my opinion.🛠
I would have just cut the drywall and ran the duct directly into the top. Now I know someone will say he is renting. But what you do is keep the piece of drywall you cut out so if you need to move, you put in back in a get the paint matched. takes very little skill to patch a hole when you have the original piece you cut out. I did this in my old apartment that had no wall large enough for any size tv but one wall. and the one wall you could put it on had no outlets so you had to run the power cord across a walk way. Behind that wall was a little closet area that have a outlets as it had the apartment wifi router in. So I cut into that wall. Ran the power in to plug in. i left the piece of drywall in the closet till i moved out. used paint sticks to back it and drilled it back in place. but before i did that, i took the piece to get paint color matched. This was actually nice because the landlord missed many areas when painting before i moved in. So everytime i showered I would see areas behind the toilet or shower with the old color. So in the end. By cutting this piece out and color matching to get paint. I actually left the unit in better condition and properly painted.
It might have some room for improvement, but Morley really nailed the spirit of makers/tinkerers, which is something I totally love. DIYers always have tons of ideas-some might seem a bit weird or not make sense at first, but that’s just part of the process. Every great invention goes through a bunch of failures and tweaks before it’s just right. It’s all about learning as you go and picking up lessons from the mistakes. I’ve learnt a lot from everyone’s comments too, and hoping Morley gets a chance to do a follow-up with an upgraded version. Keep going, Morley. I m a big fan of you. :)
I sent this video to my dad and he said something really interesting that would "dramatically improve" your invention! He said that as good as the invention is, there is no way for you to circulate the air and get enough airflow, so he said to make the little thingy at the bottom a little longer into the room, and then have a gap where you can get airflow through the crack under the door. That way he said you would get a lot more airflow! Just though that that Ideas was really cool so, do with it what you will! Also loved the video btw ❤
The odd hole here or there sure, but you literally just drilled 20ish brackets at 2 holes a pop 40 holes?! Half of which are into the ceiling?! Hah be interested to see what your landlord says in the next inspection.
That's normal in Canada. They repaint and fix everything after people leave. Unless it's something big, they don't even take your deposit over small screw holes.
Nail holes are easier to cover up than command strips that have been on the wall for a long time tbh, I always take them out wrong and it rips out a chunk of wall. A tiny nail hole is easier to patch with a tube of spackle.
So apart from the air having no way to exit your closet, your test without the vent was with the printer printing and the test with the vent didn't have the printer do anything. You're far better off by just taking the door out of the frame and then putting in something like a DIY folding door with the appropriate holes.
I would have just cut some holes. You can always patch them when you move out. Also, sorry if I missed this, but did you consider PVC pipe or even cylindrical metal ducting instead of that expanding hose? The smooth texture of PVC or metal ducting (painted white) would make it less noticeable.
My thought was a cooler and a battery powered fan blowing over it inside the closet lol. Then again, it gets to be 105 degrees F here, so $2 worth of dry ice and a little 12" fan blowing square into the box works great for a small room, just have to have air to circulate.
The problem with portable AC is the negative pressure created in your appartement when you′re cooling the heat exchange system. Basically, you′re sucking air inside your room to cool down the AC, and throwing the hot air outside... The air of your room needs to get back inside, otherwise you will just die from the lack of oxygen in your room! The only way the air comes back is from outside, which is.... hotter than inside! So you′re basically wasting a lot of energy running these system. One thing you can do to prevent this issue (which I did), is to print a cover of the air input (from the air exchanger of course) and suck the air from outside. That way you make a complete sealed system! Be aware that you need to seperate the two hose, otherwise you′ll end up sucking the hot air from the heat exchanger and your AC will die of over heating x) Sorry for my bad english, i′m French :) Cheers!
his unit IS a 2-hose system btw. The newer portable AC units combine the 2-hose into one really big looking "single hose", but its still 2 hoses. The hot air gets exhausted out of the top hose, and the intake hose gets colder air below it.
@@TheOfficialOriginalChad They are, but it′s really hard to fibd them, and even then, it′s extremely expensive compared to the single hose models :) Again I didn′t know it was that common in the US/Canada to buy dual hose system so I assumed it was a single hose one in the video. Thanks for pointing it out!
@@Xailow Other person comment that you can just fill in the small holes and nobody would know. To which I'd say: You could just fix big holes, too, and nobody would know. Just takes a little longer/more skill to do properly.
This has to be one of the most inefficient ways to use an ac. I am surprised that the air was even a little bit cold at the end off the tube. To get this setup even close to working (and I think 3 degrees Fahrenheit is not enough to proof that the setup works) you'd have to make a compromise where the cooler is placed half the distance to your office, to reduce the distance where the cool air is warmed up. Then you must use a proper heat-insulated ventilation hose to conduct the warm air out and the cool air into the office. Else all the cool air will be warmed up by the time it reaches your office. The door-gap-design must be the coup de grâce for this project, as it has 2 major flaws. First, there is a reason why every hose is round. It reduces surface area and therefore material cost - but in this case it also dramatically increases the heat released from the outside air in to your cold air stream, as heat transfer is proportional to the area. Second, even though the cross-sectional area is the same, the majority of the air is again redirected into another direction which increases friction. You should have completely evaded this problem by just going for the round hole at the top of the door, which would also safe a bit of ventilation hose and therefore cold. (and developing time for this project) Then you also have to make a hole for air going out of the room, because if you keep everything sealed, pressure in your room increases to a point, where It perfectly balances the in flow and it will result in a net flow of zero. It would be optimal to place the hole somewhere, where you know the air is the hottest for eg above your 3d printers. (So basically another tube from your printer connected to the door) While it was entertaining watching your development process, I must say that this project has to be declared a failure at this point. Not every project can turn out as a success which is completely reasonable, but I dislike when a failed project is presented as if it is a success.
A lot of people mention the insulated hose issue but an AC that size for a room that small would be overkill anyways. Plus the heat loss is into their own apartment anyways so its not a total loss. As others have mentioned, putting in a new door with ventilation is way easier (maybe sound trade off). One other thing that bothered me was that he measures the cross sectional gap under the door and claims its roughly the same area as the hose pipe then proceeds to restrict the flow by the support structures within the vent that just have tiny holes haha.
Thank you! With a tiny office like this, I think there's gonna be many more 3D printed improvements (haven't even dug into the world of storage solutions yet)
Since you have an AC you could have focused on just keeping the office as cool as the rest of the apartment. Build a strip and wedge to keep the office door ajar say four or five inches, with fans near the top and bottom to move air in and out. This would easily stick to the doorway with command strips - totally removable, no screws in the wall, no duct, no need to run a second AC unit. Having said that, I am as totally thrilled as you are with the A1/AMS combo. After five years of tinkering with my Ender 3 (which I didn't mind - it was a great way to learn about printing) it's a pleasure to use a printer that's a tool and not a project. I love having a printer that just WORKS!
my first reaction is to point out the flaw that I can see so I can feel smart but really when I remember how hard it is for me to get anything done because im a perfectionist I just admire that you did something and it has a positive result. I hope one day I can get over myself and just enjoy creating something without feeling like "i wasted all my effort because its trash."
I love your ability to finish these things, I always envied people like you in a good way :D If you still want to improve on it, you can consider: - let some air out: If your portable AC blows in new air but cant get rid of the old one, pressure will rise and it would work on a lower efficiency. If you buy a new door and make 2 new holes, then you can bring new, cold air at the bottom and get rid of the old, hot air at the top - double hose AC: now your AC work this way: it takes air from it's sides, throws some out through the hose and blows you some cold air. So it heats up some air it just cooled. You can create an attachment to the AC where it sucks in air and connect another hose in so it can take air from the outside. Maybe have some insulation for both of the hoses. This will make it way more efficient, close to split AC systems. - humidity: Have a separate unit that would make the humidity higher if it drops way too low. Low humidity will dry out your mucus in your air ways and you will be prone to catch sicknesses like the cold, flu or covid. 35% is not too bad, but do not let it drop below 30% at all - remote control: You could create a remote control in a creative way if your AC has a remote (i dont remember). You could measure the IR signals and create a transmitter that emits the signals when you press the button inside or if you dont want to code, you could 3d print a case for that remote with some mechanic fingers that you can move using hydraulics or something (suboptimal, but way cooler :D)
i was going to say the same. by pushing air into the room there needs to be a way for air to get back out too. if the only way out is around the place it comes in then you'll lose some of the colder air straight back out the gaps in the door. Though the floor fan will be helping move that air around. I'd say itd be more effective just to take the door off, store it somewhere, and get a slotted door that will allow air to escape, and then just setup a fan on the ceiling blowing air at the door. Allowing cold air from the apartment to flow into the cupboard, as the hot air get pushed out. then if he ever moves he can just put the door back up.
Great project! The main reason nobody does ventilation through the door crack is because usually if not just a mess up of the builder is to do the opposite then what you did! The crack under the door is designed to take out any excess and "used" air out of the room (to prevent air pressure vuild up which unables good circulation of air and cooling) so i would advise leaving even a small gap under the door for air to go out if you feel you need to replace the air in the room. Again really nice project and problem solving keep up!
Awesome video! Here is a different thought to help with some work flow for you too. You could automate you working in the office and turning on the AC for you. Right now it looks like when you want to work in the office, you need to manually close the vent covers, plug in the inline fan, close the door, and turn on the in room fan. Here are some things you could do to help automate that: - Get a smart plug for the inline fan - Get a smart plug for the room fan - Get a door sensor for the door - Setup an automation that says when you close the door to the room, turn on the inline and room fan, and when you open it, turn them off. This would still require you to manually close the vent covers, but there are electronic ways you could figure that out (I am just not that thoughtful), but everything else is just automatic! Keep up what you are doing though... Looks cool!
insulated smooth wall ducts will get much more efficient supply air to that room. go buy an interior door you can cut up and temporarily replace the one that is there so you can cut a hole low for the supply and one high for the "return" adding a fan on the high side of that door to draw hot humid air out will do more for the comfort in that room that the cold supply will.
I dig your enthusiasm and skill. I do think that results would be the same with corner computer fan tube that exhausts hot air from top of office into hallway. Cool air will be drawn in from the vacuum. Bonus your SO is happy you keep your stuff in the room and don't turn the apartment into a server room.
Then there is the added issue that the cold air is never being delivered around the AC unit, so the compressor in it will run non stop, more wear on it and higher electric bill. And I definitely agree, swap the door with a cheap used one and just run the duct in through a hole in the top corner. Also may not look as pretty, get rid of as many sharp bends as you can
I've been thinking about doing something similar to do this but everyone and myself have been questioning the idea of running a duct throughout the apt and this video was the push i needed to do it. Thank you!!
I enjoy having 80° F x 39-40% humidity in my home. The two back bedrooms are set to cool at around 65°F and with one ceiling fan running in the living room we maintain this temperature easily through out the day plus the split air units are set to just dehumidify and run super slow and very quiet.
Great video Morley! I remember reading somewhere that for every 90 degree bend you have, it's the equivalent of an extra meter of pipe (i.e. further pressure loss over distance)
You should also have a carbon dioxide (and monoxide because why not) detector in there, if only to make sense of why you get tired after a while I mention this because the cycling air in a car slowly builds up in carbon dioxide and is part of why drivers get sloppy
The reason the humidity "plummeted" 14:06 , is because hotter air can hold more water than cold air. In a closed box, the humidity percentage will therefor lower with a rising temperature. While the humidity in Liter/m^3, will stay the same. The percentage is just an oversimplification of humidity to let people know when it typically feels good or bad.
I don’t rent, but I LOVE renter friendly renovation! I’m the type to change up my appearance as well as my surroundings quite a bit, on the regular. Love your vids!❤
I like the “change the door out for a cheap one from a home improvement store” to add a feed and return port to, but let’s step it up a notch and add motors to access doors at the AC unit and automate the whole thing so it’ll close the doors to feed your office with cold air when temp and/or humidity hit a certain number, or for an easier automation, based off time of the day when you’ll be working in your office.
If you're pushing air in, there's got to be a way for other air to get out. Right now, it's probably just pushing out through the cracks in the door. Perhaps one solution would be to have another fan high up in the closet that sucks in warmer air and pushes it out through another duct under the door. Sure, both ducts will have to be half size, but I think it might work a lot better.
Nice work! Although you will still be slightly choking motor with open area on door outlet. Between the hose and the slot there isn’t much transition. This open area is maybe half a circumference wide and 3/4” - wall thickness tall. So even though as you said it opens up again, it will get a choking point just before this
The single hose portable ACs are suuper inefficient. Dual hose is a lot better if you have to use a portable. I know you said you were borrowing it, though. There are some awesome U shaped window units that are so quiet and efficient. Also, if I'm renting for more than 6 months, I'm dong wtf I want because patching a
Lots of good feedback here, but I havent seen anyone mention the type of ducting used. In my experience working with chip/dust extraction on CNC machines, solid ducting is far more efficient than that flexible style of ducting. I think even just replacing all the long straight runs with a bit of PVC pipe would have to at least help the situation. Definitely something to consider alongside all the other great suggestions here!
Very nice. This gives me some ideas on how to move air into my kids rooms from a main area. The tambor turned out great. Love the shout out to your mom.
The worst part about the bad AC is you have an ideal scenario. Body heat increases temps a lot too, but an x86, especially a desktop computer really pumps out the heat.
I think if the duct work were to be used as an exhaust duct, you could put a small AC unit in your office and vent out to another hole in that plexiglass piece. Something like an Ecoflow WAVE 2 would be perfect for the space. Plus it can output heat in the colder winter months.
This is a very cool design. Bravo! I only see two improvements that can be made right off the bat. 1) You could print the vent to where it is directed upward rather than having to rely on the fan. The unit would need to slide on the bottom of the door like the Nintendo switch joy-con attachments. 2) If you use HVAC flex duct you will probably see even better results since it is an insulated duct. (I do not think the white dryer vent looking duct you chose is insulated) Either way, it's really impressive to see what people with a little creativity and a 3D printer can create.
Let me pile on the criticisms, bc and easy shot is fun and good for my spirits. Get a used / cheap door as others say, if hollow, fill with spray foam to make silent, when shooting your ASMR 😅. But, 3d print for two vents with a channel block between the two flow paths though it may eat into cfm, or trim the top of door to have a fixed 3d vent on top of doorway, and other on bottom. Either way: One inflow, and one out. You _could then_ just add a small hose to the outflowing air side with the inline vent fan to add suction to remove air out of the room forcing pressure balance. In this way, you may get away just using 1 ac for the whole apt. However, you may need 2 ACs, not 1. 1 is for where its at for the apt exclusively keeping the happy wife. The other is just outside the door assuming you want inside to be quiet. Each must be a dual hose, for efficiency. Now, the cold air comes in and hot air leaves quickly, and inline fan and large hose snake isn't needed with two acs. Or, ignore the landlord, and drill holes everywhere baby; live your life, because, I know in my area they just keep the depisit anyway. I'm in Cali. Landlords are mean here to the good tenants, and good to the bad tenants. 😢
Thinking "outside the box" (there's a subtle thermodynamics heat-pump joke in there): you could pull the hinge pins and stash the door, get a 'temp' door (~US$65 at big-box-orange-or-blue), cut whatever size/shape holes you need (for BOTH cold-air-in AND warm-air-out!), and when you move out put the original door back. As you found when you had to put in the inline fan: pipes/tubes are like "resistors" in a circuit: wherever there's a bend, or the 'corrugations' of your expandable tubing, there's more-and-more back-pressure -- and while the rectangle under the door had a similar cross-section area, you were forcing circular-cross-section profile into a very constrained different VERY narrow cross-section. You're (ahem) blowing a lot of power ($) on pumping air through resistance - and that's even before you don't have a return path at all, let alone an efficient one. THAT ALL SAID - nice job, and props!
Hi Morley! Watching your channel has motivated me to start making videos. I've got a friend set up with an A1 mini and his prints are coming out amazing! Next time drill a hole through the wall 😂 after renting for 20 years i can patch a wall with toilet paper, flour, and apartment provided paint 😉
For V2 of the under door duct don't have a top plate that extends under the door. Make it butt against the door, flush with the bottom of it. That's at least another 1/8" of height. Remove the door and smoothly finish the bottom edge. Perhaps even slightly round the room side corner. The bottom plate will of course still need to extend under the door, perhaps even into the room some with a bit of kick up to direct the incoming air off the floor. The duct inlet should be higher and the top sloped sideways so it's at least a couple of inches tall at the inlet end, tapering down to gap height at the far end. Shape it right and it won't need reinforcement ribbing, like a highly domed 1940's car hood. Stiffening ribs on the bottom plate should be curved to follow/guide airflow and made wide and low like those wider speed humps used on some 25 MPH roads. Avoid sharp corners that cause turbulence. Your current design is all sharp corners. Lastly, it shouldn't span the full width of the door so air can get out of the room. A very quick and inexpensive way to smooth over the 3D printing layer lines on the inside is aluminum flue tape. The type with the peel off paper is easy to cut to shape before applying and the adhesive is super sticky. Get some thin wall PVC pipe, the stuff made for low pressure irrigation or wood shop vacuum systems, to replace all the straight runs of your flexible duct. That, along with matching PVC elbows for the corners, will drastically improve the airflow.
I find it interesting that the AC in our house went out last week here in Texas and we had to borrow a similar portable AC unit that you used to stop the temps in the house from reaching 90 degrees. We make shifted a similar vent system with boxes, blankets and fans to move air to our offices from the dining room window. Crazy how the internet works.
@@danlowe I think you misunderstand the two types of Airconditioning units. First there are stationary, wall mounted ACs. Those will recirculate the room air and use a heat exchanger that transports the heatenergy by storing it inside a liquid and radiating it to the outside air with a diffrent heatexchanging unit. Mobile ACs work with the same priciple but will use the room air to cool and radiate the heat. This means the hot air from the exhaust and the cold air that he transports is from the same room. His set up dumps the hot air directly to the outside, creating a negative pressure inside the airconditioned room. This pressure pulls fresh air from gaps inside the room. His Mobile AC is located at a diffrent, much larger room then his office. This way the AC is sucking in the fresh air from the large room and dumping the cooled fresh air inside the small room. This creates positive pressure wich pushes out the CO2 rich air. Hope this has cleared things up. If not I can just ask ChatGPT to explain this in a more understandable tone.
Where is your exhaust? This isn't going to work very well if you're sucking air in, but not exhausting air out. If you are just pushing air in, you are creating positive pressure and won't be able to cool any more beyond that. You will have cracks that air can escape, but that's not going to be enough with the closed door. Also another thing to consider is you don't need the ducting if your air conditioner unit is sized well enough to cool the entire space. If the hallway outside your office is cool, you just need a way to exchange air from your office with the hallway. As others have pointed out, get a cheap door you can cut holes into. If noise is a factor, you just need to design a intake and exhaust vent that isn't a straight shot where sound can enter and get trapped/absorbed. Ideally you want your intake and exhaust as far as part as possible, so you should put your intake on the bottom of the door, and your exhaust on the top of the door. You want fans on both, so one to pull air in, and the other to suck it out. You won't need a fan on the inside to "push air up" because if you have enough air pressure, the cool air should fill from the bottom up, with hot air from the top pushing out. You could encourage that by possibly having your intake be at a higher speed, but try them balanced first. Lastly, does your floor unit have an exhaust? Usually those floor units have 2 pipes that are supposed to go top/bottom.
Great video Morley love watching the ideas you come up with for the 3D Printing I just got the A1 and I’m loving it hope that someday I can learn how to make my own stuff. Thanks for sharing
additionally you can do this the reverse way and have the vent face outside the door and have a grow tent exhaust mounted at ceiling height in the room, now you can use it to exchange warm airafter you have to return the ac unit
I'm not sure if the before-and-after comparisons are fully fair because you were running the printer during the "before" segment, so I'm not sure if the solution is as effective as described, but I'm sure it's noticeable enough regardless! AC is so crucial.
if you blocked a small section from the inbound vent, you could uses the same idea in the room without am exhaust fan you could use the pressure difference to induce a natural convection effect and there would be more efficient room cooling.
You could shave a little bit from the bottom of the door without the management noticing if you don't go crazy. I've seen random doors with pretty large clearance. You might even be able to hide all of your AC stuff and put a rug down and call management and ask them to shave the bottom of the door for you. Another thing you might do is to unscrew the door completely, get a cheap one from the hardware store and put that one in and you can put all the holes you want to in that. Just keep the original door stored somewhere for when you move out. Living in a house has taught me that you can repair pretty much anything with things like some spackling and paint. When I lived in an apartment the only problem I had was this one wall that was wallpapered. Unless you have that specific paper there's not much you can do. Everything else is pretty much fair game, just put it back like it was when you move out. Or just don't worry about any of it because they will keep your security deposit anyway. They always find some excuse to keep the deposit.
I have a decked out X1c with 4 AMS Units and while that thing is always cranking out prints for my small shop.. I grabbed the A1 mini during their anniversary sale and man do i love that thing prints just as well as the X1 and just keeps crankin stuff out in its small form factor. It handles most of my day to day / quick prints without thinking. I almost got the A1 but with a X1x and a P1s i really wanted to give the mini a try glad i did
I think she understands that he's trying to make his office a comfortable place to be. As long as it doesn't get in the way, I'd rather someone be comfortable regardless of how something looks.
@@amullins433 I’m the provider for sure. We are lucky enough to where she doesn’t have to work and can stay home with the kids. And not whipped, it was more in a joking sense but you know what I mean.
I don't want to be rude, but I noticed that you printed in the baseline test but not in the control test (at least not in the timelaps of the edited video). Shouldn't that make it difficult to compare the two temperatures, as a 3D printer (especially without a housing) produces a lot of waste heat?
The algorithm is working. I have been thinking about making something to direct cool air from the through the wall a/c in my living room to my bedroom in my apartment. I use a fan to blow air into my bedroom from the living room but I've been thinking about running some ducting in a similar way as this.
MUCH simpler and flow-efficient solution would be getting the cheapest replacement door that you can drill round hole through. Keep the original door for the time when you move out. You can also drill a hole on the top of the door eliminating the need for the fan on the floor. Last - using cheap metal duct pipes without flex would wastly improve the air flow
While the idea is sound the execution leaves a lot to be desired. There is massive static pressure requirement coming from duct type and length used. Also if you want air conditioning to be effective you actually have to remove as much air (preferably hot) from the space as you put in. Ideally you would do this in closed loop system. Right now it looks like your AC is not only taking living room air to cool it down to push it to your work room, it also takes the same air to cool it's condenser and expels it outside creating under pressure condition inside. This not only lowers it's efficiency but also makes hot air from outside get inside through every opening it can find. Ideally you would have slight overpressure so no hot air would be coming in.
My office gets up to 32C/90F because it's an attic and our roof isn't insulated, but I can't stand working with the shitty renter-friendly AC unit I have going 24/7 because it's too loud. Got a swamp cooler too and that helps a little bit on low humidity days, but when it gets humid those don't do anything either. What I found is that it's much more important to keep airflow going 24/7, as CO buildup kinda hangs around wherever you are, so you're not maxing out the volume of that closet anyway. What I found with my mobile AC unit (different style but same concept as yours) is that even an oversized unit does not really have the capacity to cool what it says it can. The BTU calculations match, but those are ideal conditions. If you want to cool both your living room and office, make sure to buy a bigger unit.
I did exactly the same design to extract fumes from my sla printer through the slightly cracked open window a few years ago, works great but after a year or so the glue started failing so I replaced CA with epoxy. I do believe that you could improve the efficiency of this setup by extracting warm air from the top of the room and pushing it under the door, half of this output shroud seems to be non fuctional anyway, so why not use it to push the air out to reduce the positive pressure inside of the room and make the job of intake fans easier?
Did you mean 13.9 inches squared, or 13.9 square inches? Were you planning to cut off part of the bottom of the door to get those 13.9 inches squared? (193.21 square inches - at 32 inches wide, it would need to be 6.0378 inches tall). I guess.
Quick comment... You might want to reduce the length of the outlet so allow for air to leave the room. Your current design is most likely getting airlocked all HVAC systems are nominally designed for air outflow so prevent this... Be well...
That is such a clever way to respect your landlord and make it work for you. But could you put the AC in that room, rotate the inline fan and let everything exhaust out of the plexiglass? Also if you ever enclose your 3d printer you can use that to exhaust the bad smells.
Just buy a dehumidifier... Also, did you account for backpressure? Its not going to cool the room well if there's nowhere for the hot air to escape to.
Plenty of whole-house air conditioner vents are on the floor. Mine are and I don't need portable fans to blow the cool air upwards, lol. I think that portable AC is not strong enough to force air through that long vent. It will probably tear it up if you use it that way for long, plus it doesn't work. I think the humidity went down based on your weather and the added portable fan.
Would be SOO much easier to buy a new door. Put a hole at the bottom for cold air intake (another AC unit) and hole at the top for hot air exhaust (PC fan). Easier and will cool the room better, without sacrificing the main AC in the living space.
Two thoughts, 1. If you put a second online fan at the front of the chain, could you keep the vents open without hindering the cooling of the main living space while also dehumidifying the workspace? 2. Could you use the same system you’ve installed in reverse? Pull the ac unit all the way in the apartment and use the tunnel system to vent out the warm air rather than transport the cool air?
How much do the ribs and gaps in the underfloor bit reduce the airflow? I could be wrong but don't the internal ribs with holes mean that you have greatly reduced the total hole air under the door to the size of the first bit before the rib and the holes in that rib. You could put the ribs on top of the funnel. If you want to revisit your design I would suggest working backwards from your room. AKA try and get as much of the hot and humid air out of the room while forcing some new air in. if you want to stick with the under door vent then I recommend giving yourself maximum use of that gap by not having any of your 3d print taking that space. you can make a print that seals to the lowest part of the front outside of the door, then have no bottom to that vent, just get as low to the floor as it fits then add a skirt around the hall way side of the vent to stop air getting out (think hovercraft). Also If you make your transistion from hose to vent more gradual then you'll get less eddy currents slowing your air. I have loads more ideas about improvements, hit me up if you are interested. I should go back to work now.Amazing work BTW
The internal walls you put inside the door manifold are cutting your active cross-section by at least half, and having no return path is likely cutting the air flow by even more than that.
It is just important to pull the air out of the room as push it in. If you had a way to pull air out at the top of the door you would see even cooler temps.
I am thinking I would have run 6" tin duct and painted it white. It would be a much cleaner look with less friction with more air flow. and of course replace the door and cut the holes you desire. I like the work and thought for the deflector you created but would it be better to just roll the A/C to the back of the hall and send the exaust to the outside using the same ductwork?
nice build. though i think i would just take the door off and put in one of those doors that has slats all the way up it, then have the fan in the room for pulling cold air in, or blow hot air out, or get two and do both. keep the door under a bed or somewhere, behind the couch? and you can put it back up and the landlord will never even know you took it down.
my very first thought when you outlined the restrictions was under the door, my second thought was buy a cheap second hand door and hang that in place of original door putting it back when you move...
Okay, here's a quick thought Morley. Since you have access to that storage area, take the closet door off, buy a super cheap door from the home improvement store, run your duct straight in through a hole in the door, then, use a second inline fan on the outside that pulls air out from another hole in the door at the top (hot air rises). That way you have an actual air return and you will get far better ventilation, and you won't destroy your landlord's door. You might also get better cooling, because you're pulling the hot air out. Just a thought, but other than that, great video, always fun watchin you solve these problems!
I thought the same thing. It is simpler and maybe even cheaper. Depends on how much all that filament costs.
Also thought of new door, save the land lords
Yep, since the problem is venting hot humid air, put a hole in the top of the door with a pc fan. The hot humid air goes out, the cool dry air comes in the bottom, and he wouldn't need all the ducting.
Agreed! Gotta balance the air flow. Honestly, you wouldn't have needed any of the ducting at all with just a new door and two fans...
There is a ceiling vent right there in the hallway too. Just print a ceiling vent cover he can attach a duct and run it through the door and set the thermostat to fan only. A small dehumidifier might help as well.
Sorry Morley, I usually love your videos but as an HVAC guy myself I found this whole operation a bit poorly thought out, it is defiantly a way to do it... but you are missing some of the key elements in any HVAC system, VENTILATION! That gap you used at the bottom of the door is there for a reason, its called an "Undercut" and allows air circulation when doors are closed. You gotta have some way of letting the pressure out or you are just stalling your blower as it try's to pressurize the room. This effectively makes you only have small percentage of the cooling potential possible not to mention the uninsulated duct not helping your fate.
Just ditch the ducting, add some vent fans to the door, and replace it when you move out. Maybe keep part of the duct to spread the cool air further back in your hallway if necessary.
What about halving the size of the duct at the bottom of the door? Only the first bit of it has air flowing anyway, and then it frees up the rest of the door for ventilation.
Buy a new door and follow the HVAC man’s advice…. But also vent that printer fumes all the way outside. Maybe all you need to do is aggressively suck/ push the printer fumes out of that room, from an enclosed printer rack. Then that evacuation of the fumes will suck cold air in.
He's also got about 400 watts or more of heater in that small space. The printer heater cartridge and computer equipment. It's more likely the the ambient air changed than that cooling system is working. I hate those AC units because as they discharge air out the patio, they are bringing uncooled air in from the hallway or outside. You can't discharge air without make up air coming in from somewhere. He's be better off with a new door and a window unit through it, and a discharge fan at the patio door IMO.
This is the second video I've seen from this channel and both are just bad solutions.
Guy could just leave the door open.
The most amazing part of this build is that your wife is cool with that thing running across your apartment.
I thought the exact thing!
She might have said "I should have said No"
@@dnzcn-qh4wl She might have said "This video will bring in some money and we can pull it down right afterwards"
Dude… her face in the couch was epic enough to make me give up for sure.
She probably isn't, but knows it's how he's going to make money on TH-cam.
If you're going to be printing and working in that same room, you really need to add a lot of active ventilation for the printers. There are a lot more VOCs and very fine particulates coming off of printers than we used to think, and they're bad for your health long term. CO2 building up in the room from your breath could also be a problem. You might want to get a meter and see how much it rises over the day with you in the room. It'll make you sleepy and less able to think.
You could repurpose this whole system for that though! On days when it's not hot, connect the hose to the spot where the AC vents out the door and reverse your inline fan, and you'll be pulling out air! You would need a way for clean air to get in the room to replace the vented air.
With the constant/dropping humidity I'd expect enough air exchange inside this room. This will push out any VOCs/PM{2.5,10} of this tiny space as well. It's simply now a positive pressure chamber.
Exactly
I work in a room with 6 printers and have noticed zero side effects. But I only print PLA and PETG.
Resin is the most dangerous for VOCs and toxic particulates inside your lungs
@@LexxDesign3D that's the insidious thing about particulates and lung damage. You won't necessarily notice it right away. Unfortunately PLA and PETG seem to be less safe than we thought. They still generate a fair amount of VOCs and particulates, they just aren't as bad as resin. It's just one of those things where it's so simple to mitigate the risk that it's absurd to not do so.
@@evanbarnes9984 agreed, those effects don’t show up for years, just ask someone who is dying of lung cancer who gave up smoking 10 years ago.
You need to use insulated ducts, you're losing all of the effectiveness because the cool temp is being loss through the duct. If you touch your ducts they will be cold especially closest to the AC Unit. Using an inline fan will only force air, but its still losing cooling through the material of the duct. Use an insulated duct to fix this problem. Also remove half of the side of your floor baffle that isnt effective. You need a way for air to push out of the room equally as important as air being pushed in. I would buy a smaller AC unit for your office and push the hot air out through the duct system you made, and let the AC blow cold air into your studio, that would really drop the temps.
Exactly. I just wanted to suggest the same thing!
Yeah, I'm really surprised he never considered how air would leave the room.
This, exactly. Plus, your support ribs for the door plenum block too much airflow, they only had a few small circles cut in them. If you measure their total area, you'd see that your available airflow area is less than 20% of what you calculated for the door gap. Shrink the door plenum to 50% width, and redesign the support ribs to be in the direction of airflow, not against them (think marble run channels), to divvy up the airflow and spread it across the gap without impeding airflow. With these changes, you'll likely double the airflow over your current solution.
Yep, very good point. It's way easier to push the hot air out of that room to atmosphere and cool it directly rather than cooling it from a distance with no way for the hot air to release
I wish i had the optimism to completely fail and clutter my whole house up and still take it as a win
I wasn’t going to say it but ya 80 is still hot af my house stays at 69 100% of the time 80 is way to hot to be a success
As a landlord, I would never have noticed if you had just sanded the bottom of the door to make it level :)
As a renter, I totally would have noticed if YOU had just sanded the bottom of the door to make it level. :)
Cool, but you need a way for air to get OUT too for it to really be effective. I'm glad it helped as much as it did though!
There is no air in without air out, there are still gaps in other places of the room where air will get out. It's now a positive pressure room ^.^
What I thought...
Unfortunately I am very hard feeling pressure changes and would get headaches with this approach. Good when it is working for you...🎉
@@sydnerd Yeah, obviously no air would come in if no air could get out. That's kinda my point though... Limited air out means limited air in.
@@sydnerdNot true, there can be air in without air out. Air is a compressible fluid.
Additionally, the harder it is for it to exhaust hot air, the more friction in the system, the harder it is to move the air into the room. With just that little inline fan, that translates to less are moved.
I was thinking this too. Perhaps the gaps around the side/top of the door are large enough? It must be going somewhere.
Crazy thought, but if you're not allowed to make holes, why not replace the door with your own custom (pallet/recycled wood?) door that has all the features you need? Cool video, still renter friendly
Or a second hand hollow core door that you can hack
Yes, the opening for the door duct has, "sufficient" volume, but one major thing you overlooks, is the connection between the adapter and the tube. You're effectively going from an open pipe to a tiny sliver or a cylinder that then flares out. If you want greater airflow (there are other more important things that could be improved actually), it would be better to shape the adapter like a wide-nozzle vacuum attachment. It would spread the volume of air more evenly across the floor adapter before it flows out and under the door.
I'm hesitant to believe you actually think this was a good execution and result, I'm sorry...
1. In the before, your 3D-printer was running, in the after it was not.
2. There's no air return, making the whole system inefficient and you're not venting out CO2 or VOC's from the printers.
3. You made at least 30 screwholes following a pattern, not exactly the same as hanging a few pictures.
4. Painting everything white doesn't make it not ugly.
I would love to see you revisit this with all the good feedback from the comments (temporary door, air return, AC inside the cupboard, CO2-monitor). Onwards and upwards!
Almost all of his videos are like this. He sells failures as sucusses. He's supposed to be an engineer but he misses crucial details that drive him to redo everything. He just doesn't seem to have any well thought out processes. He's just not cut out for the whole "inventor" thing.
@@TechnologistAtWorki was gonna say that redoing everything is very common in engineering, but i'm now more concerned about you. you've commented 15 times on this channel, all of them in an extremely negative way. why do you even watch his videos if you don't enjoy them?
@@Thomas-sg4iz His videos are suggested to me. And no that's not how prototyping works. I'm an engineer myself and prototyping is mainly improving a product but fixing fatal flaws. If you scrap your work so much and redo it from scratch then you don't know what you're doing.
Look up any popular product prototypes, they're usually a gradual improvement not total failures and start over.
He didn't see the airflow impedance over a long distance, he didn't see the gap variance for that door. All his videos are like that but he keeps claiming that he's an inventor. There is stuff that he makes you could easily not see them working then the results are expected by the end of the video. There's a bit of arrogance in the things he says and it's fascinating watching him fumble at the end, yet he learns nothing and always has a positive take instead of acknowledging his mistakes.
Then comes you. No clue about how engineers work yet you're trying to pick an argument about it. That's just bizarre. Are you his lawyer?
@@TechnologistAtWork Reminds me of the "I like to make stuff" channel. They guy acts like he's got a plan, that the knows what he's doing, and is all, "You just do this..." - but then his videos are him backtracking a ton, restarting completely, stumbling the entire way, and in the end, he's all, "Well, this doesn't do exactly what I set out to do", or "So, this didn't actually work at all, but maybe you could pull it off with..."
And it's like, guy - I just watched your twenty minute video, and you didn't actually do anything worth doing/you took the worst possible path/you could have Googled any of this before starting and it would have been so much easier and faster.
You should have used as much straight and smooth piping as possible. That would have made the airflow a lot less turbulent and it would have improved the look in my opinion.🛠
I would have just cut the drywall and ran the duct directly into the top. Now I know someone will say he is renting. But what you do is keep the piece of drywall you cut out so if you need to move, you put in back in a get the paint matched. takes very little skill to patch a hole when you have the original piece you cut out.
I did this in my old apartment that had no wall large enough for any size tv but one wall. and the one wall you could put it on had no outlets so you had to run the power cord across a walk way. Behind that wall was a little closet area that have a outlets as it had the apartment wifi router in. So I cut into that wall. Ran the power in to plug in. i left the piece of drywall in the closet till i moved out. used paint sticks to back it and drilled it back in place. but before i did that, i took the piece to get paint color matched. This was actually nice because the landlord missed many areas when painting before i moved in. So everytime i showered I would see areas behind the toilet or shower with the old color. So in the end. By cutting this piece out and color matching to get paint. I actually left the unit in better condition and properly painted.
It might have some room for improvement, but Morley really nailed the spirit of makers/tinkerers, which is something I totally love. DIYers always have tons of ideas-some might seem a bit weird or not make sense at first, but that’s just part of the process. Every great invention goes through a bunch of failures and tweaks before it’s just right. It’s all about learning as you go and picking up lessons from the mistakes. I’ve learnt a lot from everyone’s comments too, and hoping Morley gets a chance to do a follow-up with an upgraded version. Keep going, Morley. I m a big fan of you. :)
I love you bro, but that white ducting along the ceiling... Eden is a saint for tolerating that ;)
im sure the paycheck he gets from making content outweighs style.
I sent this video to my dad and he said something really interesting that would "dramatically improve" your invention! He said that as good as the invention is, there is no way for you to circulate the air and get enough airflow, so he said to make the little thingy at the bottom a little longer into the room, and then have a gap where you can get airflow through the crack under the door. That way he said you would get a lot more airflow! Just though that that Ideas was really cool so, do with it what you will! Also loved the video btw ❤
>renter friendly
>drills into the walls
i don't think we have the same landlord
Every apartment I’ve lived in, we patch whatever holes we make and it’s fine 🤷♂️
They usually repaint between tenants anyway
The odd hole here or there sure, but you literally just drilled 20ish brackets at 2 holes a pop 40 holes?! Half of which are into the ceiling?! Hah be interested to see what your landlord says in the next inspection.
That's normal in Canada. They repaint and fix everything after people leave. Unless it's something big, they don't even take your deposit over small screw holes.
Nail holes are easier to cover up than command strips that have been on the wall for a long time tbh, I always take them out wrong and it rips out a chunk of wall. A tiny nail hole is easier to patch with a tube of spackle.
So apart from the air having no way to exit your closet, your test without the vent was with the printer printing and the test with the vent didn't have the printer do anything.
You're far better off by just taking the door out of the frame and then putting in something like a DIY folding door with the appropriate holes.
I would have just cut some holes. You can always patch them when you move out. Also, sorry if I missed this, but did you consider PVC pipe or even cylindrical metal ducting instead of that expanding hose? The smooth texture of PVC or metal ducting (painted white) would make it less noticeable.
I'm going to be honest, it would have been way cheaper, easier, and cleaner to just buy a new cheap door, and install a box fan in to it
box fans push out hot air, though. He'd boil his girlfriend!
@@Thomas-sg4iz his gf has an AC she'd be fine.
A dehumidifier with a container you just dump woulda been just as efficient
My thought was a cooler and a battery powered fan blowing over it inside the closet lol.
Then again, it gets to be 105 degrees F here, so $2 worth of dry ice and a little 12" fan blowing square into the box works great for a small room, just have to have air to circulate.
@@jameskirk3 If you want to kill yourself!? Dry ice is solid CO2 and when it sublimates it will fill the room with CO2 gas.
The problem with portable AC is the negative pressure created in your appartement when you′re cooling the heat exchange system.
Basically, you′re sucking air inside your room to cool down the AC, and throwing the hot air outside...
The air of your room needs to get back inside, otherwise you will just die from the lack of oxygen in your room!
The only way the air comes back is from outside, which is.... hotter than inside! So you′re basically wasting a lot of energy running these system.
One thing you can do to prevent this issue (which I did), is to print a cover of the air input (from the air exchanger of course) and suck the air from outside. That way you make a complete sealed system!
Be aware that you need to seperate the two hose, otherwise you′ll end up sucking the hot air from the heat exchanger and your AC will die of over heating x)
Sorry for my bad english, i′m French :)
Cheers!
Yep, however 2 hose AC's are sold as well.
@@marsrover001 Not in France :/
@@Les12flinguesyes they are sold in France.
What do you think the french government has some sort of import law on air intakes? 🤣
his unit IS a 2-hose system btw. The newer portable AC units combine the 2-hose into one really big looking "single hose", but its still 2 hoses. The hot air gets exhausted out of the top hose, and the intake hose gets colder air below it.
@@TheOfficialOriginalChad They are, but it′s really hard to fibd them, and even then, it′s extremely expensive compared to the single hose models :)
Again I didn′t know it was that common in the US/Canada to buy dual hose system so I assumed it was a single hose one in the video. Thanks for pointing it out!
"Renter friendly", proceeds to drill a ton of holes into the wall and ceiling...
You can spackle them in 35 seconds flat and they'd be none the wiser tbh. It's nbd.
Renters can drill little holes in the wall, not big ones
@@Xailow Other person comment that you can just fill in the small holes and nobody would know.
To which I'd say: You could just fix big holes, too, and nobody would know. Just takes a little longer/more skill to do properly.
This has to be one of the most inefficient ways to use an ac. I am surprised that the air was even a little bit cold at the end off the tube.
To get this setup even close to working (and I think 3 degrees Fahrenheit is not enough to proof that the setup works) you'd have to make a compromise where the cooler is placed half the distance to your office, to reduce the distance where the cool air is warmed up. Then you must use a proper heat-insulated ventilation hose to conduct the warm air out and the cool air into the office. Else all the cool air will be warmed up by the time it reaches your office.
The door-gap-design must be the coup de grâce for this project, as it has 2 major flaws.
First, there is a reason why every hose is round. It reduces surface area and therefore material cost - but in this case it also dramatically increases the heat released from the outside air in to your cold air stream, as heat transfer is proportional to the area.
Second, even though the cross-sectional area is the same, the majority of the air is again redirected into another direction which increases friction. You should have completely evaded this problem by just going for the round hole at the top of the door, which would also safe a bit of ventilation hose and therefore cold. (and developing time for this project)
Then you also have to make a hole for air going out of the room, because if you keep everything sealed, pressure in your room increases to a point, where It perfectly balances the in flow and it will result in a net flow of zero.
It would be optimal to place the hole somewhere, where you know the air is the hottest for eg above your 3d printers. (So basically another tube from your printer connected to the door)
While it was entertaining watching your development process, I must say that this project has to be declared a failure at this point. Not every project can turn out as a success which is completely reasonable, but I dislike when a failed project is presented as if it is a success.
A lot of people mention the insulated hose issue but an AC that size for a room that small would be overkill anyways. Plus the heat loss is into their own apartment anyways so its not a total loss. As others have mentioned, putting in a new door with ventilation is way easier (maybe sound trade off).
One other thing that bothered me was that he measures the cross sectional gap under the door and claims its roughly the same area as the hose pipe then proceeds to restrict the flow by the support structures within the vent that just have tiny holes haha.
@@EdTse88 I completely missed that he restricted air flow with the additional wall lol
It's so cool to see this project come together! I absolutely love the home improvement type stuff with 3D printing, it's so fun and creative!
Thank you! With a tiny office like this, I think there's gonna be many more 3D printed improvements (haven't even dug into the world of storage solutions yet)
My mind is blown that you are comfortable at 80 degrees! and if 62% humidity is a problem you should avoid the entire South eastern US.
Since you have an AC you could have focused on just keeping the office as cool as the rest of the apartment. Build a strip and wedge to keep the office door ajar say four or five inches, with fans near the top and bottom to move air in and out. This would easily stick to the doorway with command strips - totally removable, no screws in the wall, no duct, no need to run a second AC unit.
Having said that, I am as totally thrilled as you are with the A1/AMS combo. After five years of tinkering with my Ender 3 (which I didn't mind - it was a great way to learn about printing) it's a pleasure to use a printer that's a tool and not a project. I love having a printer that just WORKS!
my first reaction is to point out the flaw that I can see so I can feel smart but really when I remember how hard it is for me to get anything done because im a perfectionist I just admire that you did something and it has a positive result.
I hope one day I can get over myself and just enjoy creating something without feeling like "i wasted all my effort because its trash."
I love your ability to finish these things, I always envied people like you in a good way :D
If you still want to improve on it, you can consider:
- let some air out: If your portable AC blows in new air but cant get rid of the old one, pressure will rise and it would work on a lower efficiency. If you buy a new door and make 2 new holes, then you can bring new, cold air at the bottom and get rid of the old, hot air at the top
- double hose AC: now your AC work this way: it takes air from it's sides, throws some out through the hose and blows you some cold air. So it heats up some air it just cooled. You can create an attachment to the AC where it sucks in air and connect another hose in so it can take air from the outside. Maybe have some insulation for both of the hoses. This will make it way more efficient, close to split AC systems.
- humidity: Have a separate unit that would make the humidity higher if it drops way too low. Low humidity will dry out your mucus in your air ways and you will be prone to catch sicknesses like the cold, flu or covid. 35% is not too bad, but do not let it drop below 30% at all
- remote control: You could create a remote control in a creative way if your AC has a remote (i dont remember). You could measure the IR signals and create a transmitter that emits the signals when you press the button inside or if you dont want to code, you could 3d print a case for that remote with some mechanic fingers that you can move using hydraulics or something (suboptimal, but way cooler :D)
Maybe use half the door to get air in and the other half to get it out?
i was going to say the same. by pushing air into the room there needs to be a way for air to get back out too. if the only way out is around the place it comes in then you'll lose some of the colder air straight back out the gaps in the door. Though the floor fan will be helping move that air around.
I'd say itd be more effective just to take the door off, store it somewhere, and get a slotted door that will allow air to escape, and then just setup a fan on the ceiling blowing air at the door. Allowing cold air from the apartment to flow into the cupboard, as the hot air get pushed out.
then if he ever moves he can just put the door back up.
There’s not much hot air at the floor, so a bottom mounted exhaust will not have a positive impact.
Great project!
The main reason nobody does ventilation through the door crack is because usually if not just a mess up of the builder is to do the opposite then what you did!
The crack under the door is designed to take out any excess and "used" air out of the room (to prevent air pressure vuild up which unables good circulation of air and cooling) so i would advise leaving even a small gap under the door for air to go out if you feel you need to replace the air in the room.
Again really nice project and problem solving keep up!
Awesome video! Here is a different thought to help with some work flow for you too. You could automate you working in the office and turning on the AC for you. Right now it looks like when you want to work in the office, you need to manually close the vent covers, plug in the inline fan, close the door, and turn on the in room fan. Here are some things you could do to help automate that:
- Get a smart plug for the inline fan
- Get a smart plug for the room fan
- Get a door sensor for the door
- Setup an automation that says when you close the door to the room, turn on the inline and room fan, and when you open it, turn them off.
This would still require you to manually close the vent covers, but there are electronic ways you could figure that out (I am just not that thoughtful), but everything else is just automatic!
Keep up what you are doing though... Looks cool!
insulated smooth wall ducts will get much more efficient supply air to that room.
go buy an interior door you can cut up and temporarily replace the one that is there so you can cut a hole low for the supply and one high for the "return" adding a fan on the high side of that door to draw hot humid air out will do more for the comfort in that room that the cold supply will.
I dig your enthusiasm and skill. I do think that results would be the same with corner computer fan tube that exhausts hot air from top of office into hallway. Cool air will be drawn in from the vacuum. Bonus your SO is happy you keep your stuff in the room and don't turn the apartment into a server room.
You could have used PVC which would have allowed a lot less friction.
Just wanted to add love for the A1, got mine a few weeks ago and it's incredible!
Then there is the added issue that the cold air is never being delivered around the AC unit, so the compressor in it will run non stop, more wear on it and higher electric bill. And I definitely agree, swap the door with a cheap used one and just run the duct in through a hole in the top corner. Also may not look as pretty, get rid of as many sharp bends as you can
I've been thinking about doing something similar to do this but everyone and myself have been questioning the idea of running a duct throughout the apt and this video was the push i needed to do it. Thank you!!
It's backwards. Have the portable Ac in the room and duct the "exhaust" air outside.
Morley always finds new things to do that help others! At least it helped me! Thanks for the video! Keep the good Work!
Curious: how did it help?
@@ellabun I have a treehouse in my garden and it gets really hot in there so i am going to do the same as morley
I enjoy having 80° F x 39-40% humidity in my home. The two back bedrooms are set to cool at around 65°F and with one ceiling fan running in the living room we maintain this temperature easily through out the day plus the split air units are set to just dehumidify and run super slow and very quiet.
Great video Morley! I remember reading somewhere that for every 90 degree bend you have, it's the equivalent of an extra meter of pipe (i.e. further pressure loss over distance)
You should also have a carbon dioxide (and monoxide because why not) detector in there, if only to make sense of why you get tired after a while
I mention this because the cycling air in a car slowly builds up in carbon dioxide and is part of why drivers get sloppy
The reason the humidity "plummeted" 14:06 , is because hotter air can hold more water than cold air.
In a closed box, the humidity percentage will therefor lower with a rising temperature. While the humidity in Liter/m^3, will stay the same.
The percentage is just an oversimplification of humidity to let people know when it typically feels good or bad.
I don’t rent, but I LOVE renter friendly renovation! I’m the type to change up my appearance as well as my surroundings quite a bit, on the regular. Love your vids!❤
I like the “change the door out for a cheap one from a home improvement store” to add a feed and return port to, but let’s step it up a notch and add motors to access doors at the AC unit and automate the whole thing so it’ll close the doors to feed your office with cold air when temp and/or humidity hit a certain number, or for an easier automation, based off time of the day when you’ll be working in your office.
If you're pushing air in, there's got to be a way for other air to get out. Right now, it's probably just pushing out through the cracks in the door. Perhaps one solution would be to have another fan high up in the closet that sucks in warmer air and pushes it out through another duct under the door. Sure, both ducts will have to be half size, but I think it might work a lot better.
Nice work! Although you will still be slightly choking motor with open area on door outlet. Between the hose and the slot there isn’t much transition. This open area is maybe half a circumference wide and 3/4” - wall thickness tall. So even though as you said it opens up again, it will get a choking point just before this
Can you remake a "I invented something every day" please, because most of the things were for your van, love your videos!
Excellent idea
The single hose portable ACs are suuper inefficient. Dual hose is a lot better if you have to use a portable. I know you said you were borrowing it, though. There are some awesome U shaped window units that are so quiet and efficient. Also, if I'm renting for more than 6 months, I'm dong wtf I want because patching a
Lots of good feedback here, but I havent seen anyone mention the type of ducting used. In my experience working with chip/dust extraction on CNC machines, solid ducting is far more efficient than that flexible style of ducting. I think even just replacing all the long straight runs with a bit of PVC pipe would have to at least help the situation. Definitely something to consider alongside all the other great suggestions here!
Very nice. This gives me some ideas on how to move air into my kids rooms from a main area. The tambor turned out great. Love the shout out to your mom.
The worst part about the bad AC is you have an ideal scenario. Body heat increases temps a lot too, but an x86, especially a desktop computer really pumps out the heat.
I think if the duct work were to be used as an exhaust duct, you could put a small AC unit in your office and vent out to another hole in that plexiglass piece. Something like an Ecoflow WAVE 2 would be perfect for the space. Plus it can output heat in the colder winter months.
You basically created a nascar exhaust called a boom tube to run your AC under the door 😂 I love it
This is a very cool design. Bravo! I only see two improvements that can be made right off the bat.
1) You could print the vent to where it is directed upward rather than having to rely on the fan. The unit would need to slide on the bottom of the door like the Nintendo switch joy-con attachments.
2) If you use HVAC flex duct you will probably see even better results since it is an insulated duct. (I do not think the white dryer vent looking duct you chose is insulated)
Either way, it's really impressive to see what people with a little creativity and a 3D printer can create.
You’re too nice man , I would have just gotten the hole saw out and cut a big old hole in the drywall and fix later LOL. Great work and ingenuity!
Let me pile on the criticisms, bc and easy shot is fun and good for my spirits.
Get a used / cheap door as others say, if hollow, fill with spray foam to make silent, when shooting your ASMR 😅.
But, 3d print for two vents with a channel block between the two flow paths though it may eat into cfm, or trim the top of door to have a fixed 3d vent on top of doorway, and other on bottom. Either way: One inflow, and one out. You _could then_ just add a small hose to the outflowing air side with the inline vent fan to add suction to remove air out of the room forcing pressure balance. In this way, you may get away just using 1 ac for the whole apt.
However, you may need 2 ACs, not 1. 1 is for where its at for the apt exclusively keeping the happy wife. The other is just outside the door assuming you want inside to be quiet. Each must be a dual hose, for efficiency.
Now, the cold air comes in and hot air leaves quickly, and inline fan and large hose snake isn't needed with two acs.
Or, ignore the landlord, and drill holes everywhere baby; live your life, because, I know in my area they just keep the depisit anyway. I'm in Cali. Landlords are mean here to the good tenants, and good to the bad tenants. 😢
Thinking "outside the box" (there's a subtle thermodynamics heat-pump joke in there): you could pull the hinge pins and stash the door, get a 'temp' door (~US$65 at big-box-orange-or-blue), cut whatever size/shape holes you need (for BOTH cold-air-in AND warm-air-out!), and when you move out put the original door back.
As you found when you had to put in the inline fan: pipes/tubes are like "resistors" in a circuit: wherever there's a bend, or the 'corrugations' of your expandable tubing, there's more-and-more back-pressure -- and while the rectangle under the door had a similar cross-section area, you were forcing circular-cross-section profile into a very constrained different VERY narrow cross-section. You're (ahem) blowing a lot of power ($) on pumping air through resistance - and that's even before you don't have a return path at all, let alone an efficient one. THAT ALL SAID - nice job, and props!
Hi Morley! Watching your channel has motivated me to start making videos. I've got a friend set up with an A1 mini and his prints are coming out amazing! Next time drill a hole through the wall 😂 after renting for 20 years i can patch a wall with toilet paper, flour, and apartment provided paint 😉
all in all this was a great video, and nice way of thinking outside the box, or quiet literally, thinking beneath the door
I love you're videos Morley!!!
Keep up the good work man
For V2 of the under door duct don't have a top plate that extends under the door. Make it butt against the door, flush with the bottom of it. That's at least another 1/8" of height. Remove the door and smoothly finish the bottom edge. Perhaps even slightly round the room side corner. The bottom plate will of course still need to extend under the door, perhaps even into the room some with a bit of kick up to direct the incoming air off the floor.
The duct inlet should be higher and the top sloped sideways so it's at least a couple of inches tall at the inlet end, tapering down to gap height at the far end. Shape it right and it won't need reinforcement ribbing, like a highly domed 1940's car hood. Stiffening ribs on the bottom plate should be curved to follow/guide airflow and made wide and low like those wider speed humps used on some 25 MPH roads. Avoid sharp corners that cause turbulence. Your current design is all sharp corners. Lastly, it shouldn't span the full width of the door so air can get out of the room.
A very quick and inexpensive way to smooth over the 3D printing layer lines on the inside is aluminum flue tape. The type with the peel off paper is easy to cut to shape before applying and the adhesive is super sticky.
Get some thin wall PVC pipe, the stuff made for low pressure irrigation or wood shop vacuum systems, to replace all the straight runs of your flexible duct. That, along with matching PVC elbows for the corners, will drastically improve the airflow.
I find it interesting that the AC in our house went out last week here in Texas and we had to borrow a similar portable AC unit that you used to stop the temps in the house from reaching 90 degrees. We make shifted a similar vent system with boxes, blankets and fans to move air to our offices from the dining room window. Crazy how the internet works.
I love seeing your inventions, and ideas come to life! Super cool
Co2 will be a problem too.
Not with fresh air being pumped in by the AC
@@LemonsRage You mean fresh CO2
@@danlowe I think you misunderstand the two types of Airconditioning units.
First there are stationary, wall mounted ACs. Those will recirculate the room air and use a heat exchanger that transports the heatenergy by storing it inside a liquid and radiating it to the outside air with a diffrent heatexchanging unit.
Mobile ACs work with the same priciple but will use the room air to cool and radiate the heat. This means the hot air from the exhaust and the cold air that he transports is from the same room. His set up dumps the hot air directly to the outside, creating a negative pressure inside the airconditioned room. This pressure pulls fresh air from gaps inside the room.
His Mobile AC is located at a diffrent, much larger room then his office. This way the AC is sucking in the fresh air from the large room and dumping the cooled fresh air inside the small room. This creates positive pressure wich pushes out the CO2 rich air.
Hope this has cleared things up. If not I can just ask ChatGPT to explain this in a more understandable tone.
@@danlowewhat in the “missing brain cells” are you ON?? Fresh CO2 😂
We don’t breathe in fresh CO2, we NEED OXYGEN. 🤣 🤣 🤣 🤣 woooow that was funny
@@whydontyouaskmehe said PUSH OUT CO2 AIR AND FILL IN WITH FRESH AIR I think your the dumb one
Where is your exhaust? This isn't going to work very well if you're sucking air in, but not exhausting air out. If you are just pushing air in, you are creating positive pressure and won't be able to cool any more beyond that. You will have cracks that air can escape, but that's not going to be enough with the closed door. Also another thing to consider is you don't need the ducting if your air conditioner unit is sized well enough to cool the entire space. If the hallway outside your office is cool, you just need a way to exchange air from your office with the hallway. As others have pointed out, get a cheap door you can cut holes into. If noise is a factor, you just need to design a intake and exhaust vent that isn't a straight shot where sound can enter and get trapped/absorbed. Ideally you want your intake and exhaust as far as part as possible, so you should put your intake on the bottom of the door, and your exhaust on the top of the door. You want fans on both, so one to pull air in, and the other to suck it out. You won't need a fan on the inside to "push air up" because if you have enough air pressure, the cool air should fill from the bottom up, with hot air from the top pushing out. You could encourage that by possibly having your intake be at a higher speed, but try them balanced first.
Lastly, does your floor unit have an exhaust? Usually those floor units have 2 pipes that are supposed to go top/bottom.
Great video Morley love watching the ideas you come up with for the 3D Printing I just got the A1 and I’m loving it hope that someday I can learn how to make my own stuff. Thanks for sharing
additionally you can do this the reverse way and have the vent face outside the door and have a grow tent exhaust mounted at ceiling height in the room, now you can use it to exchange warm airafter you have to return the ac unit
I'm not sure if the before-and-after comparisons are fully fair because you were running the printer during the "before" segment, so I'm not sure if the solution is as effective as described, but I'm sure it's noticeable enough regardless! AC is so crucial.
if you blocked a small section from the inbound vent, you could uses the same idea in the room without am exhaust fan you could use the pressure difference to induce a natural convection effect and there would be more efficient room cooling.
You could shave a little bit from the bottom of the door without the management noticing if you don't go crazy. I've seen random doors with pretty large clearance. You might even be able to hide all of your AC stuff and put a rug down and call management and ask them to shave the bottom of the door for you. Another thing you might do is to unscrew the door completely, get a cheap one from the hardware store and put that one in and you can put all the holes you want to in that. Just keep the original door stored somewhere for when you move out. Living in a house has taught me that you can repair pretty much anything with things like some spackling and paint. When I lived in an apartment the only problem I had was this one wall that was wallpapered. Unless you have that specific paper there's not much you can do. Everything else is pretty much fair game, just put it back like it was when you move out. Or just don't worry about any of it because they will keep your security deposit anyway. They always find some excuse to keep the deposit.
I have a decked out X1c with 4 AMS Units and while that thing is always cranking out prints for my small shop.. I grabbed the A1 mini during their anniversary sale and man do i love that thing prints just as well as the X1 and just keeps crankin stuff out in its small form factor. It handles most of my day to day / quick prints without thinking. I almost got the A1 but with a X1x and a P1s i really wanted to give the mini a try glad i did
The way your wife puts up with your add ons is mind blowing. My fiance would've bit my head off lmao. Love to see it
I think she understands that he's trying to make his office a comfortable place to be. As long as it doesn't get in the way, I'd rather someone be comfortable regardless of how something looks.
@@crispy_orb I’m with you 1000%. I was just saying my fiance would tell me to figure out a different way haha
@@macko4l sound whipped... whos the money maker you or her? Don't let someone boss you around.
@@amullins433 I’m the provider for sure. We are lucky enough to where she doesn’t have to work and can stay home with the kids. And not whipped, it was more in a joking sense but you know what I mean.
I don't want to be rude, but I noticed that you printed in the baseline test but not in the control test (at least not in the timelaps of the edited video). Shouldn't that make it difficult to compare the two temperatures, as a 3D printer (especially without a housing) produces a lot of waste heat?
The algorithm is working. I have been thinking about making something to direct cool air from the through the wall a/c in my living room to my bedroom in my apartment. I use a fan to blow air into my bedroom from the living room but I've been thinking about running some ducting in a similar way as this.
MUCH simpler and flow-efficient solution would be getting the cheapest replacement door that you can drill round hole through. Keep the original door for the time when you move out. You can also drill a hole on the top of the door eliminating the need for the fan on the floor. Last - using cheap metal duct pipes without flex would wastly improve the air flow
While the idea is sound the execution leaves a lot to be desired. There is massive static pressure requirement coming from duct type and length used. Also if you want air conditioning to be effective you actually have to remove as much air (preferably hot) from the space as you put in. Ideally you would do this in closed loop system. Right now it looks like your AC is not only taking living room air to cool it down to push it to your work room, it also takes the same air to cool it's condenser and expels it outside creating under pressure condition inside. This not only lowers it's efficiency but also makes hot air from outside get inside through every opening it can find. Ideally you would have slight overpressure so no hot air would be coming in.
My office gets up to 32C/90F because it's an attic and our roof isn't insulated, but I can't stand working with the shitty renter-friendly AC unit I have going 24/7 because it's too loud. Got a swamp cooler too and that helps a little bit on low humidity days, but when it gets humid those don't do anything either.
What I found is that it's much more important to keep airflow going 24/7, as CO buildup kinda hangs around wherever you are, so you're not maxing out the volume of that closet anyway.
What I found with my mobile AC unit (different style but same concept as yours) is that even an oversized unit does not really have the capacity to cool what it says it can. The BTU calculations match, but those are ideal conditions. If you want to cool both your living room and office, make sure to buy a bigger unit.
Could have printed that cheap stuff with a better printer. Anyways a hole in drywall is easier to patch then the work you put in.
I did exactly the same design to extract fumes from my sla printer through the slightly cracked open window a few years ago, works great but after a year or so the glue started failing so I replaced CA with epoxy. I do believe that you could improve the efficiency of this setup by extracting warm air from the top of the room and pushing it under the door, half of this output shroud seems to be non fuctional anyway, so why not use it to push the air out to reduce the positive pressure inside of the room and make the job of intake fans easier?
Did you mean 13.9 inches squared, or 13.9 square inches? Were you planning to cut off part of the bottom of the door to get those 13.9 inches squared? (193.21 square inches - at 32 inches wide, it would need to be 6.0378 inches tall). I guess.
Quick comment... You might want to reduce the length of the outlet so allow for air to leave the room. Your current design is most likely getting airlocked all HVAC systems are nominally designed for air outflow so prevent this...
Be well...
Have you watched Terry Gilliam's _Brazil_ lately? Ducts!!!
😉👍
Nice to see, once again, the Leatherman Skeletool on the job!
Cheers.
That is such a clever way to respect your landlord and make it work for you. But could you put the AC in that room, rotate the inline fan and let everything exhaust out of the plexiglass? Also if you ever enclose your 3d printer you can use that to exhaust the bad smells.
Just buy a dehumidifier...
Also, did you account for backpressure? Its not going to cool the room well if there's nowhere for the hot air to escape to.
Plenty of whole-house air conditioner vents are on the floor. Mine are and I don't need portable fans to blow the cool air upwards, lol. I think that portable AC is not strong enough to force air through that long vent. It will probably tear it up if you use it that way for long, plus it doesn't work. I think the humidity went down based on your weather and the added portable fan.
Just as sn FYI, when figting against gravity, command strips are substantially stronger against shearing forces when mounted vertically.
Would be SOO much easier to buy a new door. Put a hole at the bottom for cold air intake (another AC unit) and hole at the top for hot air exhaust (PC fan). Easier and will cool the room better, without sacrificing the main AC in the living space.
I don't want to add to internet negativity, so I'll just give you an A for effort
Two thoughts,
1. If you put a second online fan at the front of the chain, could you keep the vents open without hindering the cooling of the main living space while also dehumidifying the workspace?
2. Could you use the same system you’ve installed in reverse? Pull the ac unit all the way in the apartment and use the tunnel system to vent out the warm air rather than transport the cool air?
How much do the ribs and gaps in the underfloor bit reduce the airflow? I could be wrong but don't the internal ribs with holes mean that you have greatly reduced the total hole air under the door to the size of the first bit before the rib and the holes in that rib. You could put the ribs on top of the funnel.
If you want to revisit your design I would suggest working backwards from your room. AKA try and get as much of the hot and humid air out of the room while forcing some new air in. if you want to stick with the under door vent then I recommend giving yourself maximum use of that gap by not having any of your 3d print taking that space. you can make a print that seals to the lowest part of the front outside of the door, then have no bottom to that vent, just get as low to the floor as it fits then add a skirt around the hall way side of the vent to stop air getting out (think hovercraft). Also If you make your transistion from hose to vent more gradual then you'll get less eddy currents slowing your air.
I have loads more ideas about improvements, hit me up if you are interested. I should go back to work now.Amazing work BTW
The internal walls you put inside the door manifold are cutting your active cross-section by at least half, and having no return path is likely cutting the air flow by even more than that.
literally as you explained your issue i was thinking ' push it under the door ' but my idea was not as simple as yours right off the bat lol
One thing I’ve noticed with PLA on the A1 is when printing large you need to turn down the bed temp 65 is way too hot. I turned mine down to 40.
The most amazing part of the video is Canadian landlords being okay with you drilling 40 screwholes into the walls and ceiling
It is just important to pull the air out of the room as push it in. If you had a way to pull air out at the top of the door you would see even cooler temps.
I am thinking I would have run 6" tin duct and painted it white. It would be a much cleaner look with less friction with more air flow. and of course replace the door and cut the holes you desire. I like the work and thought for the deflector you created but would it be better to just roll the A/C to the back of the hall and send the exaust to the outside using the same ductwork?
I believe no one ever did the air entrance below the door because cold air go down and hot air go up, thats why A/Cs are on the top of the walls.
nice build.
though i think i would just take the door off and put in one of those doors that has slats all the way up it, then have the fan in the room for pulling cold air in, or blow hot air out, or get two and do both.
keep the door under a bed or somewhere, behind the couch? and you can put it back up and the landlord will never even know you took it down.
my very first thought when you outlined the restrictions was under the door, my second thought was buy a cheap second hand door and hang that in place of original door putting it back when you move...