I would have felt guilty about putting nitrogen in the system, and would have paid for replacement if needed, also, I've never seen anyone purge nitrogen like that before, nice job!
This is what I was thinking also. This is one reason I'm hesitant about calling people to do work for me. I've been in situations where a tech would damage something by mistake but I would have to pay for it. I learned to do a lot of things myself over the years because of this though haha
There was a restriction in the metering device before he put nitrogen in the system. What he did was not the reason for the repair. Really he just got lucky that he had to recover the charge already anyways haha
I just wanted to say, it's extremly nice that you share your screw-ups too and let everybody learn from. When I'm working on such things, I get very suspicious if I'm doing a measurement and I get "nothing" as a result. Even on electric circuits, getting a wrong voltage feels better than getting exactly 0V, because it tells you at least that your measurement is working (and you have to check the function of your meter anyway). On refrigeration circuits I feel good when I'm reading a little bit above "nothing", maybe 2..3psi. If I'm reading zero, I start to do something like pressing Schraders to confirm this, because it makes me dubious about my measurement.
If I think a unit is out of gas I'll depress the Schrader before putting gauges on it, if it squirts gauges go on. Keep up the good work, awesome videos as always.
@@HVACRVIDEOS i was curious that why Carrier just keep using the coremax . it is so stupid. and i don't have the tool to replace the core everytime i just add a JB tee in to it if i find the leak from it. good video as always thanks
You’re absolutely right. That’s what I do first before putting on the gauge manifold’s hose to be sure there is pressure before putting on gas or adding refrigerant.
I am glad to see I am not the only one who starts with voltages checks. Enjoyed watching this. One time my boss went with me on a residential service call and after the gauges were on and I checked the super heat he asked for my diagnosis. I said a coil is blocked. He went into the attic only to find that coil was super clean. He said that the unit needed refrigerant. I disagreed and he asked why. I said A coil is blocked, I never sail the evaporator coil was. I asked him to move three feet to his left and look behind the condenser coil. There was a clothes dryer vent directly behind the unit and we found the back of the condenser coil was completely blocked with lint. I am unsure if this was a test or if he had tried to fix this before me and failed. Once we cleared all of the lint, the system worked perfectly. Q&A for yall: what is the largest copper line any of you have brazed? For me it was 1 5/8" & not fun as it was also my first forearm burn, the size of an egg.
Old school techs , before all the regulations hit , they used to vent non condensables the way you did . As far as the billing and all that , in all honesty if it was me I would kick myself for not checking that the schrader was correctly depressed , like taking my gauges off and depressing the core with a screwdriver or something . I got fooled by a core not depressing before and now I'm very careful and apprehensive with trusting schraders . That being said we usually have to learn these things the hard way innit .
Thousands of pounds for just one rack system alone if work needed to be done on high side and system could not be isolated was standard daily practice. A pallet full of 30# R22 jugs or a dozen are so 100# refillable cylinders to to re- charge only one unit! --The good old days when a 30# jug of r12 cost
People can give there opinions but it’s different when you are in the moment and working. Nice to see you think your way through that. Like you said I wish you would’ve kept the camera rolling through the frustration. Would of made me feel better when I do it 😂
Read a few of the posts. I agreed with just putting virgin R22 in, just to avoid any other issues for this unit. If I had no pressure on either gauge, I would have reseated my blue tooth gauges and checked by depressing schrader core with screw driver tip. We are under the gun most of the time and try to make good decisions and do our best. We don’t have to worry about 100* temps here (Wisconsin). I like watching these to see what tools other techs are using and picking up different techniques other tech have. Thanks keep it going. I’ll invite you to a roof here when it’s -20* for a no heat call.
Air is lighter than R-22 so it will separate and float above the R-22 like oil and water. The bucket idea was genius, I usually let it sit over night in a temperature controlled room. If you crack the valve you will hear the whistle sound change as the R-22 comes up. You can also hear this when bleeding air out of a hose. If the pressure temperature relationship matches the refrigerant it is good to go.
I noticed the rapid rise right away. Look. Its so easy to armchair quarterback these things and your straight forward reflection is commendable. I have made this same mistake. Especially in the old days (1970 s...did I just date myself?) Had a system that wouldn't take gas. Bugged me for a while till the realization set in. GREAT video. I would apprentice under you in a heartbeat!
What a mental rollercoaster that job would have been, all I was thinking when you were replacing that EVAP was its already recently had a new compressor and now a new evaporator the condenser looks like shit so they may as well just load the parts cannon whilst it was apart and thrown a new condenser at it too 😐 it really makes you wonder how they see it justifiable to keep chucking parts at old degraded and worn out equipment.
SO many places are based upon 1-3-6 month budgets versus 2-3-5 year budgets that give them the ability to spend a little more now to save a big amount later.
I’ve been here and done this! I personally, would have sold them new refrigerant because I don’t trust myself venting out the nitrogen properly. And you never know what kind of contaminants are mixed in with the refrigerant. I do like how you look out for your customers to try to save them money, as long as it doesn’t affect the system. And I love the new way of you doing your videos. I know it’s more work, but it is a much better way of explaining your thought process and what is happening. Keep up the great work!
Thank you for the first 5 minutes of explaining the sequence of operation with the wiring. My field supervisor just did the same thing on the phone with me on Friday to diagnose a blown transformer that I possible grounded out during routing visual inspection/filter change on Thursday. It was on the exact same WeatherMaster unit. I'm new to HVACR and find all your videos to be so informative. Thanks Chris!
I will be going live on TH-cam this evening 10/11/21 @ 5:PM (pacific) to discuss my recent uploads and answer questions from TH-cam comments, emails and the Livechat, come over and check it out th-cam.com/video/Mf8BPexYVhA/w-d-xo.html
I had to do that recocering r123 out of a low pressure chiller. Those run in a vaccum so when they have a leak they suck in air. A couple minutes into the recovery we popped the high pressure on the recovery machine, we had to periodically bleed off the top of the tank to save 1200lbs of gas at a couple G$/100lbs.
I watched this video at just the right time. Thanks for the tip on the Sumner 2124 lift. Never would have thought of using it like that outside of a building. (13:37)
I love your videos. That happens to me also when I just put in the gauge’s hose without noticing the Schrader valve tip bent thereby concluded that the unit is out of gas. Experiences teach us a lot. More power to you💪
Those coremax schraders are notorious for bent stems, I am sure you'll be looking next time before you put the gauges on( I personally try to look at all schrader stems, it's just a good habit before putting on gauges). I probably would have met the customer halfway on the new refrigerant because it did have a full charge and the nitrogen was kind of a screw-up. Chris you still go the extra mile on some of the older equipment but there does come a time when you start throwing good money on top of bad. You did a great job, the only thing different I would have done would be new refrigerant and 4 oz to 8 oz of AC renew for the lost oil. I just happen to love that AC renew, is it just me (?).
Thanks for the flow explanation in the beginning of the video. I like the new style when you stop to add detail when it is necessary, it helps those that are not in the industry understand what is going on. I have to agree with that company, I think I would continue to repair the equipment after you mentioned all the crap they have to go thru to replace a unit, will open up several cans or worms for sure. Thanks for continuing to make these video's!
I’ve gotten fooled with the schrader valve before! Boss wasn’t to happy but it is what it is! I don’t think you were wrong if you had to change the refrigerant. Awesome video, thank you!
This one was great. This reminds us to not assume the simple basic things are ok like a schrader valve. This shows anything is possible because both valves were bad. This would of messed me up too. Great teaching video. Thank you!
We have done that venting on recovery cylinders. We have a few facilities that have big leaks the customers don’t want to fix and their old units. On site engineers just dump 22 in. Found out they never purged their gauges and it eventually bit them. Only works for air like noncondensables. Can’t do that with moisture or fractionizarion. That won’t work with blends either. Awesome vid Chris, thanks for cutting up that evap header for us to see!
its a very old system rescuing old R22 refrigereant i an outstanding decision. The PT chart bucket method to rescue R22 is valid given the resources at hand in my opinion. I would have done the same thing and test it out. If the system works which seems like it did then i would keep else i consider replacing. About the Shrader issue it is the previous technicians responsibility, i have to clean up others mess more often than not in particular wiring and rubouts.
Awesome job man! I replaced the metering devices and liquid header on a similar unit. What a pain in the ass, i should have just quoted a new evap lol.
Hey man it happens sometimes. Doesn't matter how good you are sometimes you over look very simple things. It's funny cause I just had a unit a couple weeks ago that I thought had a bad compressor but turned out my depressors were to far back and I wasn't depressing the shreader. I initially had pressure, but when it turned it looked like no pumping.
I would have done the same. You said it best that it wasn’t your fault the shraders were shot. I’ve seen it far too many times myself. Now I may have pushed them manually just to see if anything spit out but otherwise no issues with me charging em under these circumstances! BTW - I get the same nonsense with the alternatives…..
Although the logic is plausible, regarding pressure/temp relationships, I would sleep better knowing virgin refrigerant was added, to remove any doubt of trace amounts of non-condensibles. This in essence, makes the customer “whole” again. I do respect this….be humble to see your mistakes, be courageous to admit them, and be wise enough to correct them. 🤜🤛
The nitrogen isn't combining with the liquid R22, just the vapor at the top of the tank. Leaving it sit would allow the nitrogen to float on top and then venting vapor out until refrigerant came out would all but guarantee there's little to no nitrogen left.
We had some issue with schradercores and a certain kind of quickconnect fittig. The way you use the quickconnect you have to actuate a valve on the quickconnect itself to open the schrader. Some genius made the valve plunger LONGER than the travel distance of the schradercore which would lead to you bending the living daylight out of the schradercore, wrecking it in the process.
I really appreciate that you are brave enough to post mistakes. Next time check wich pressure switch is open first and all this will be avoided. But now I know how to get nitrogen out of refrigerant.
6:51 I had that happen when I tried to add air in my car tires a few weeks ago... I knew there was air in them, but on one of them the gauge didn't pick up any pressure... then a slight touch of the trigger shot the pressure way up. First I was like WTF... And that happened at another station too, it appears the pin on that valve is a bit too short, whatever, but the depressor does not quite engage it without using high force. I did get them all topped up but that one required some sweet words and coercion.
I am not in the business but have watched many of your videos. This was the first time that you mentioned the red tape involved with installing a new unit. It changed my previous opinion that they were just kicking the problem down the road. All that red tape has costs included besides dealing all the "problems" that the inspections add to the cost. In a similar vein, my appliance guy told me I should keep my ancient clothes washer and dryer going as long as I could because the modern versions have much higher repair costs.
Any time I even suspect a low charge before I even touch the service valves I run an electronic leak test on them. I want to be sure they are not the source of the leak because opening the valves you may create a new leak or stop an previous leak.
Lots of extra precautions in an earthquake zone . You did the right thing by a customer and I am sure you will credit him for some Freon 22. Good video.
Recently I was pulling the gas out of one with cormax fittings. I only had one depressor so I only connected one hose, but didn't cap the other side. Oops! Recovery machine wouldn't pull into a vacuum. Scratching my head what the heck, the leak can't be that big. Suddenly I realized, sucking air into the system through the other cormax fitting! The large disk seal will lift if the pressure is greater on the outside. Air is lighter than R-22 so it will separate and float above the R-22. If you crack the valve you can hear the whistle change sound as the refrigerant starts to come out. I've let them sit over night in a controlled temperature room I never thought about the bucket idea.
Dealing with old units with new edicts... my apologies, policies, is damn difficult. Up in Alaska, it's damn difficult to replace equipment between shipping to the state followed by shipment to the location so we end up doing "repairs" and that's before the politics get involved. I'm sorry to hear about your predicaments.
Before we start let’s just say I hate the fact CA is STILL doing ac lol. Salt Lake City has started heating season since Monday. Can’t say why but I’ve always leaned towards refrigeration. Those heating seasons when they come at you. Your still thinking “ahhh shwwwt what’s the sequence of operations?” Lol GREAT VIDEO CHRIS AS ALWAYS 👍. Let’s talk about them Water boilers & them gummies let’s get to work haha
If there's any mixture in a refer circuit, other than the refrigerant (because blended refrigerants are a thing), all kinds of fuckery starts happening. Jumping pressures, superheat and subcooling readings that make no sense and usually compressor failure.
Yeah, it ruins the PT characteristics of the refrigerant. I think you could get away with a very small amount but its usually just recovered then reclaimed/recycled or destroyed.
It wouldn't ruin it. R22 isn't a blend and the two would be separated. He bled it off so it's all good. If you left it in there, it will throw off compression and expansion properties of the refrigerant causing cooling issues and possible wear from messing with the oil traveling in the system. With a blended refrigerant I'm not sure how it'd work out because the gases can separate so you'd ruin some of the characteristics by trying to bleed vapor. I think a specialized recovery machine would be used at that point to refine it back to a proper refrigerant.
A little excess heat shouldn't damage the filter drier, they usually just contain molecular sieves. They're zeolite adsorbant beads. They can be "recharged" and dried with heat of a few hundred degrees.
Impossible to find a schrader issue when you working on things STUFF happens. Any of the posters including me have done things much worse. Hindsight is always 20/20 especially if your not the one that made the mistake Good job saving the refrigerant
We all work under the assumption that the simple things just works and that the schrader valves just do that and at worst they leak. But there's a movie quote from the movie "Under Siege 2" where it's stated "Assumption is the mother of all F-ups". That's one of the truest quotes from a movie. How successful you are is only measured by the end result, not the way you took. In most conditions nitrogen is pretty inert and harmless, but you could probably get improper pressure readings if you have too much nitrogen in the system. At some stage it might be worth to consider a refrigerant recovery system that can purify the refrigerants, but I assume that's a pretty expensive investment.
I have seen those coremax valves go crooked, brazing in the suction or discharge lines on a compressor changeout, the heat can cook them real good. Can be tricky when they are 6" from braze points.
Hey, I hate those carrier scraders! I don't change them I replace them! I use the regular ones. All my customers still want R-22! Even tho there are good drop in replacement gases. I've done the bleed off trick also too! I have polished a few turds in my time! I couldn't imagine doing work in your state!
If you are planing there will be chips😁 In my opinion you did a good job. Sometimes I'm in a similar situation and had to decide what kind of failure diagnostic strategy I use to find a fault. If my choice was suboptimal there will be a little bit more chips on the floor😁 There is a tomorrow everytime.
When I have a CLO lockout, I reset the power to see what will happen. Once I find power on X, I check for a call. If I have to, I place a jumper first and then test the system to see if it can run. If I can see evidence of a working compressor (as in having gas in the system to do work, such as a temp dropping on the suction line) then I know if I gauge up and see no pressure, it's those coremax valves again. I carry spares on the truck when I get approval to do the repair. Replacing the evap is a good move, but as you found out, the newer evaps don't fit. We had to hack up a 14 year old TME to fit the new part earlier this year. Carrier never got back to me when I told them about the issue, so I'm sure that they were told to not discuss this screwup. I stopped replacing orifices three years ago, because it does not always fix the problem. It may be a problem of thickened oil pooling in the evap or large plugs of wax after the orifice...I haven't taken one home to do an autopsy. The evaps go to the boss' house and are Company scrap. I will sometimes try heating them with pressure on the suction side and an open liquid line, and if that doesn't work, it's big bucks time. Oh, well. I didn't tell them to not use a nice Sporlan TEV. I already have two units lined up for evaps next cooling season. I just remind myself that I didn't design this junk.
Completely ethical in my view. I believe if absolutely necessary you could've charged for new gas as well, but you did the best for this turd. Great job with these videos, much help.
We don't ever touch or use Coremax fittings around here. I believe they don't even accept regular hose fittings? Systems I see have coremax and regular service acsess fittings. Why mess with such BS fittings? Faster evacuation for little 5/10 ton units!? Very foolish$$ for the engineering genius's who think we need two different access fittings right next to eachother when most times they can't even include just one! Bigger Systems we pull vacuum through king valves and other types of full flow service valves. Why does Coremax exist is a good question Excellent job on getting creative with recovering from your mistake though. I've developed purging habits that probably are unessessary for fear of not wanting to get any air into a system. One tip. If you think you might be in a vacuum before putting low side guage on then shut off system to give best chance of not hooking up on a vacuum that sucks in hose air. CA does sound retarded. Less hassle to pay more to fix vs. replace Never heard of such anywhere else
I replace the CoreMax Cores, but I remove the whole center. I install a swivel tee w/ cores on both ports. Then Nylog & Torque everything down. If you need to service after, then you use VCRT’s.
That’s a bad part about those high flow cores. To much side to side play of the plunger. I have a video showing a O ring melted on the core also preventing the plunger from depressing. It happens!
My personal opinion is that you did what was best. I can't remember the phase diagram of nitrogen but I imagine it's boiling point under these pressures is lower than the refrigerant. You quoted them a full charge and were able to vent off the nitrogen for the most part. I used to work in automotive both as a mechanic and as a parts peddler and I always give a worse case scenario. Even if I don't think that's the problem I always let the customer know what the absolute worst is. It's always better to over quote and under charge than one quote and over charge.
We've all done things we'd wish we'd spent just 5 seconds longer thinking it through. My first boss said to me "never assume" That bit of advice bites me time and time again.. However blowing off the nitro and re-using the charge on the job is a personal choice. In this situation considering the customer had already approved new gas on the job I would have recharged with new, taken the old back to the yard and let it sit a while and vent off there . Once happy, that cylinder would go as van stock.. Either way it's no biggie and don't beat yourself up over it.Loved the drier falling off I'm usually swearing my head off by that point :-) . All back up and running = Great job
I think we all have done or will do that during our career. I did put nitrogen on top of the charge thinking it was flat, and it was the core depressor valve that was broken. We just have to laugh and move on. Sometimes we like to jump into conclusions because it look so obvious, old unit , leak are common, no pressure= we think it’s flat.
I've been told by my supervisor before that if you see that a unit low on gas or completely flat. Don't add nitrogen on top of the refrigerant you just add refrigerant, and search for leak which confused me because I thought that adding nitrogen on top was standard practice
Omg I just subscribed to your channel and I’m going through so much similar problems you’ve encountered with carrier it’s uncanny. I’m recently going through contractor chatting and with your video ima look into pressure sensors, also I to had a carrier that I thought was flat and yes why does carrier install those core max service ports?, I looked into that “special tool” and it was like 700.00
Chillers do the same thing with a dedicated purge unit on top of the condenser. So this was an excellent use of your skill and understanding of how refrigerant works. This should be a presentation for hvac school.
32:51 okay that's funny but I was just recently trained over a year ago that if I have to recover what I believe to be a system contaminated with non-condensables that I can do pretty much what you just did they do recommend stabilizing it over many hours as the only difference like in your shop with just the tank, but this is a real world situation and I like how you used the water to speed up the process and get the job done in a reasonable amount of time. I do believe that was also in training materials somewhere.
Oh Chris I was you would have come to a Starbucks in Ottawa to fix our ice machine I told them what I learned I told them the condenser could be iced up or réfringent leak it was not making ice at all.
Interesting perspective, I will discuss this on my livestream this evening 10/11/21 @ 5:PM (pacific) come over and check it out th-cam.com/video/Mf8BPexYVhA/w-d-xo.html
I would have done exactly what you did on the refrigerant. We both know plenty of people that would charge for virgin refrigerant no matter what which is not a bad thing. I prefer to stick with OEM and not redesign a system.
It never occurred to me to purge non condensables like that but I’ve also never accidentally put nitrogen on top of r-22. Easy mistake to make though, I’ve also never seen both valves go bad like that either
You are supposed to clean the refrigerate by running it through a filter dryer from a tank to another, if you are going to reuse refrigerate according to the EPA law.
Seeing as I have no experience with HVAC, I do find your videos very interesting and I'm learning alot. General question: You showed that the carrier unit used two single phase contactors between lines 1, 2 and 3. Wouldn't it be more efficient to replace those two contactors with one 3-phase contactor that I've seen so many of the other units have? Or is just not possible/worth it? Thanks for the videos, Chris, and keep up the great work!
That wouldn't work. The contactors each control separate devices by switching two of the three phases. This fully opens the circuit, even though there's still a hot leg going to the motor, that energy has nowhere to go. I do three phase work for my job often, and I would personally really prefer true three-phase contactors, but I understand why they went the less expensive route.
As for liability, you know that those valves are prone to going bad and not opening. You should have noticed they were faulty when you removed the caps. Luckily you saved the gas but I believe as an experienced tech you should have noticed the condition of the valves before connecting to them. Did you make a note of the time wasted and not bill for it?
I've wondered if it might be possible to save refrigerant gas mixed with a small amount of nitrogen (or possibly another non-refrigerant gas). Had it not worked out, I'm not sure I would have charged the customer for all new refrigerant. I might split/pro-rate it. (But take that for what it is from a largely "armchair" technician who doesn't do this as his primary source of livelihood.) I caught what happened the first time, though I wasn't totally certain why.
The link I sent is for trutechtools if you end up purchasing one do me a favor and use my offer code (bigpicture) one word at checkout to get a discount and in turn I get a commission
@@arthouston7361 I was thinking in general terms , none the less I went to google earth re counted and it was twice as many then I thought not only was the vibration an issue but each fan is creating a downward force on the roof ( there was one large package unit the rest were splits )
I would have felt guilty about putting nitrogen in the system, and would have paid for replacement if needed, also, I've never seen anyone purge nitrogen like that before, nice job!
This is what I was thinking also. This is one reason I'm hesitant about calling people to do work for me. I've been in situations where a tech would damage something by mistake but I would have to pay for it. I learned to do a lot of things myself over the years because of this though haha
There was a restriction in the metering device before he put nitrogen in the system. What he did was not the reason for the repair. Really he just got lucky that he had to recover the charge already anyways haha
I just wanted to say, it's extremly nice that you share your screw-ups too and let everybody learn from.
When I'm working on such things, I get very suspicious if I'm doing a measurement and I get "nothing" as a result. Even on electric circuits, getting a wrong voltage feels better than getting exactly 0V, because it tells you at least that your measurement is working (and you have to check the function of your meter anyway). On refrigeration circuits I feel good when I'm reading a little bit above "nothing", maybe 2..3psi. If I'm reading zero, I start to do something like pressing Schraders to confirm this, because it makes me dubious about my measurement.
"What we have is a legend right here...."..yes we do.....that's exactly how I feel every time I watch one of your videos........
Thanks for the nice words bud!!
If I think a unit is out of gas I'll depress the Schrader before putting gauges on it, if it squirts gauges go on. Keep up the good work, awesome videos as always.
I will too but a cormax Schrader is almost impossible to depress by hand... the spring is so big its very difficult
@@HVACRVIDEOS i was curious that why Carrier just keep using the coremax . it is so stupid. and i don't have the tool to replace the core everytime i just add a JB tee in to it if i find the leak from it. good video as always thanks
Heh these cormaxes has given me so many similar troubles! And yes for manually checking for liquid in the liquid line!
You’re absolutely right. That’s what I do first before putting on the gauge manifold’s hose to be sure there is pressure before putting on gas or adding refrigerant.
That’s probably how those got bent.
Man, you scienced the hell out of that Nitrogen. I like it! :)
I am glad to see I am not the only one who starts with voltages checks. Enjoyed watching this.
One time my boss went with me on a residential service call and after the gauges were on and I checked the super heat he asked for my diagnosis. I said a coil is blocked. He went into the attic only to find that coil was super clean. He said that the unit needed refrigerant. I disagreed and he asked why. I said A coil is blocked, I never sail the evaporator coil was. I asked him to move three feet to his left and look behind the condenser coil. There was a clothes dryer vent directly behind the unit and we found the back of the condenser coil was completely blocked with lint. I am unsure if this was a test or if he had tried to fix this before me and failed. Once we cleared all of the lint, the system worked perfectly.
Q&A for yall: what is the largest copper line any of you have brazed? For me it was 1 5/8" & not fun as it was also my first forearm burn, the size of an egg.
I love how you braze. Bigger the gob the better the job!
Old school techs , before all the regulations hit , they used to vent non condensables the way you did .
As far as the billing and all that , in all honesty if it was me I would kick myself for not checking that the schrader was correctly depressed , like taking my gauges off and depressing the core with a screwdriver or something .
I got fooled by a core not depressing before and now I'm very careful and apprehensive with trusting schraders .
That being said we usually have to learn these things the hard way innit .
Thousands of pounds for just one rack system alone if work needed to be done on high side and system could not be isolated was standard daily practice.
A pallet full of 30# R22 jugs or a dozen are so 100# refillable cylinders to to re- charge only one unit!
--The good old days when a 30# jug of r12 cost
thx Chris, this is a learning experience for us. and i will now check the schraders now.
That first couple minutes of you telling the sequence of operations was awesome!!
People can give there opinions but it’s different when you are in the moment and working. Nice to see you think your way through that. Like you said I wish you would’ve kept the camera rolling through the frustration. Would of made me feel better when I do it 😂
I will discuss this on my livestream this evening 10/11/21 @ 5:PM (pacific) come over and check it out th-cam.com/video/Mf8BPexYVhA/w-d-xo.html
Read a few of the posts. I agreed with just putting virgin R22 in, just to avoid any other issues for this unit. If I had no pressure on either gauge, I would have reseated my blue tooth gauges and checked by depressing schrader core with screw driver tip. We are under the gun most of the time and try to make good decisions and do our best. We don’t have to worry about 100* temps here (Wisconsin). I like watching these to see what tools other techs are using and picking up different techniques other tech have. Thanks keep it going. I’ll invite you to a roof here when it’s -20* for a no heat call.
Air is lighter than R-22 so it will separate and float above the R-22 like oil and water. The bucket idea was genius, I usually let it sit over night in a temperature controlled room. If you crack the valve you will hear the whistle sound change as the R-22 comes up. You can also hear this when bleeding air out of a hose. If the pressure temperature relationship matches the refrigerant it is good to go.
I noticed the rapid rise right away. Look. Its so easy to armchair quarterback these things and your straight forward reflection is commendable. I have made this same mistake. Especially in the old days (1970 s...did I just date myself?) Had a system that wouldn't take gas. Bugged me for a while till the realization set in. GREAT video. I would apprentice under you in a heartbeat!
What a mental rollercoaster that job would have been, all I was thinking when you were replacing that EVAP was its already recently had a new compressor and now a new evaporator the condenser looks like shit so they may as well just load the parts cannon whilst it was apart and thrown a new condenser at it too 😐
it really makes you wonder how they see it justifiable to keep chucking parts at old degraded and worn out equipment.
SO many places are based upon 1-3-6 month budgets versus 2-3-5 year budgets that give them the ability to spend a little more now to save a big amount later.
R-22 is such a good refrigerant they made the jug green to represent money
I’ve been here and done this! I personally, would have sold them new refrigerant because I don’t trust myself venting out the nitrogen properly. And you never know what kind of contaminants are mixed in with the refrigerant.
I do like how you look out for your customers to try to save them money, as long as it doesn’t affect the system. And I love the new way of you doing your videos. I know it’s more work, but it is a much better way of explaining your thought process and what is happening. Keep up the great work!
Lets get some HVACR VIDEOS on a Sunday morning
Thank you for the first 5 minutes of explaining the sequence of operation with the wiring. My field supervisor just did the same thing on the phone with me on Friday to diagnose a blown transformer that I possible grounded out during routing visual inspection/filter change on Thursday. It was on the exact same WeatherMaster unit. I'm new to HVACR and find all your videos to be so informative. Thanks Chris!
I will be going live on TH-cam this evening 10/11/21 @ 5:PM (pacific) to discuss my recent uploads and answer questions from TH-cam comments, emails and the Livechat, come over and check it out th-cam.com/video/Mf8BPexYVhA/w-d-xo.html
Your best teaching video so far Chris thank you so much. We all love you brother
I had to do that recocering r123 out of a low pressure chiller. Those run in a vaccum so when they have a leak they suck in air. A couple minutes into the recovery we popped the high pressure on the recovery machine, we had to periodically bleed off the top of the tank to save 1200lbs of gas at a couple G$/100lbs.
I don't do commercial, so these step by step walkthroughs are AWESOME. Thanks man!
I watched this video at just the right time. Thanks for the tip on the Sumner 2124 lift. Never would have thought of using it like that outside of a building. (13:37)
I probably would have ate the refrigerant cost, but that agreeableness and conflict avoidance is partly why my handyman company died many years ago.
I love your videos. That happens to me also when I just put in the gauge’s hose without noticing the Schrader valve tip bent thereby concluded that the unit is out of gas. Experiences teach us a lot. More power to you💪
I will discuss this on my livestream this evening 10/11/21 @ 5:PM (pacific) come over and check it out th-cam.com/video/Mf8BPexYVhA/w-d-xo.html
Those coremax schraders are notorious for bent stems, I am sure you'll be looking next time before you put the gauges on( I personally try to look at all schrader stems, it's just a good habit before putting on gauges). I probably would have met the customer halfway on the new refrigerant because it did have a full charge and the nitrogen was kind of a screw-up. Chris you still go the extra mile on some of the older equipment but there does come a time when you start throwing good money on top of bad. You did a great job, the only thing different I would have done would be new refrigerant and 4 oz to 8 oz of AC renew for the lost oil. I just happen to love that AC renew, is it just me (?).
Thanks for the flow explanation in the beginning of the video. I like the new style when you stop to add detail when it is necessary, it helps those that are not in the industry understand what is going on. I have to agree with that company, I think I would continue to repair the equipment after you mentioned all the crap they have to go thru to replace a unit, will open up several cans or worms for sure. Thanks for continuing to make these video's!
I’ve gotten fooled with the schrader valve before! Boss wasn’t to happy but it is what it is! I don’t think you were wrong if you had to change the refrigerant. Awesome video, thank you!
I will discuss this on my livestream this evening 10/11/21 @ 5:PM (pacific) come over and check it out th-cam.com/video/Mf8BPexYVhA/w-d-xo.html
Glad I'm not the only one that has that Schrade problem.
This one was great. This reminds us to not assume the simple basic things are ok like a schrader valve. This shows anything is possible because both valves were bad. This would of messed me up too. Great teaching video. Thank you!
We have done that venting on recovery cylinders. We have a few facilities that have big leaks the customers don’t want to fix and their old units. On site engineers just dump 22 in. Found out they never purged their gauges and it eventually bit them.
Only works for air like noncondensables. Can’t do that with moisture or fractionizarion. That won’t work with blends either. Awesome vid Chris, thanks for cutting up that evap header for us to see!
its a very old system rescuing old R22 refrigereant i an outstanding decision. The PT chart bucket method to rescue R22 is valid given the resources at hand in my opinion. I would have done the same thing and test it out. If the system works which seems like it did then i would keep else i consider replacing. About the Shrader issue it is the previous technicians responsibility, i have to clean up others mess more often than not in particular wiring and rubouts.
Watching your videos is definitely making me a better tech…keep up the good work.
Awesome job man! I replaced the metering devices and liquid header on a similar unit. What a pain in the ass, i should have just quoted a new evap lol.
Literally did the same thing the other day but by the stroke of luck figured it out right before the nitro dump
Hey man it happens sometimes. Doesn't matter how good you are sometimes you over look very simple things. It's funny cause I just had a unit a couple weeks ago that I thought had a bad compressor but turned out my depressors were to far back and I wasn't depressing the shreader. I initially had pressure, but when it turned it looked like no pumping.
Appreciate the ride along, TNX!
I would have done the same. You said it best that it wasn’t your fault the shraders were shot. I’ve seen it far too many times myself. Now I may have pushed them manually just to see if anything spit out but otherwise no issues with me charging em under these circumstances! BTW - I get the same nonsense with the alternatives…..
Although the logic is plausible, regarding pressure/temp relationships, I would sleep better knowing virgin refrigerant was added, to remove any doubt of trace amounts of non-condensibles. This in essence, makes the customer “whole” again. I do respect this….be humble to see your mistakes, be courageous to admit them, and be wise enough to correct them. 🤜🤛
The nitrogen isn't combining with the liquid R22, just the vapor at the top of the tank. Leaving it sit would allow the nitrogen to float on top and then venting vapor out until refrigerant came out would all but guarantee there's little to no nitrogen left.
Jam min, my thoughts exactly but I'm glad you put it in words, because it's quite obvious you're more articulate than me.📚
We had some issue with schradercores and a certain kind of quickconnect fittig. The way you use the quickconnect you have to actuate a valve on the quickconnect itself to open the schrader.
Some genius made the valve plunger LONGER than the travel distance of the schradercore which would lead to you bending the living daylight out of the schradercore, wrecking it in the process.
But of course lol
It's the same on automotive stuff, you don't run the valve on the quick connects open all the way because it'll over depress the schraders.
I really appreciate that you are brave enough to post mistakes. Next time check wich pressure switch is open first and all this will be avoided.
But now I know how to get nitrogen out of refrigerant.
6:51 I had that happen when I tried to add air in my car tires a few weeks ago... I knew there was air in them, but on one of them the gauge didn't pick up any pressure... then a slight touch of the trigger shot the pressure way up. First I was like WTF... And that happened at another station too, it appears the pin on that valve is a bit too short, whatever, but the depressor does not quite engage it without using high force. I did get them all topped up but that one required some sweet words and coercion.
Dang it's like almost 5am here in California when you post this
Watching it now at 2 pm
That was Great!....I try to save the customer money as well....at least when I am able to....Thanks for the teaching friend!
I am not in the business but have watched many of your videos. This was the first time that you mentioned the red tape involved with installing a new unit. It changed my previous opinion that they were just kicking the problem down the road. All that red tape has costs included besides dealing all the "problems" that the inspections add to the cost. In a similar vein, my appliance guy told me I should keep my ancient clothes washer and dryer going as long as I could because the modern versions have much higher repair costs.
Any time I even suspect a low charge before I even touch the service valves I run an electronic leak test on them. I want to be sure they are not the source of the leak because opening the valves you may create a new leak or stop an previous leak.
Thanks for the clear information.
I been waiting for this video. I have the same unit on the top of the shop. It's been having problems running on ac.
almost always, always use virgin (new refrigerant) you did a good job, I always find those core max depressors bent or leaning.
Holy crap-seismic testing--Sounds like everybody's got there hand in the cookie jar!!
Lots of extra precautions in an earthquake zone . You did the right thing by a customer and I am sure you will credit him for some Freon 22. Good video.
I was able to re use all the refrigerant so I didn't have to charge him for any of it
Recently I was pulling the gas out of one with cormax fittings. I only had one depressor so I only connected one hose, but didn't cap the other side. Oops! Recovery machine wouldn't pull into a vacuum. Scratching my head what the heck, the leak can't be that big. Suddenly I realized, sucking air into the system through the other cormax fitting! The large disk seal will lift if the pressure is greater on the outside.
Air is lighter than R-22 so it will separate and float above the R-22. If you crack the valve you can hear the whistle change sound as the refrigerant starts to come out. I've let them sit over night in a controlled temperature room I never thought about the bucket idea.
Dealing with old units with new edicts... my apologies, policies, is damn difficult. Up in Alaska, it's damn difficult to replace equipment between shipping to the state followed by shipment to the location so we end up doing "repairs" and that's before the politics get involved. I'm sorry to hear about your predicaments.
Before we start let’s just say I hate the fact CA is STILL doing ac lol. Salt Lake City has started heating season since Monday. Can’t say why but I’ve always leaned towards refrigeration. Those heating seasons when they come at you. Your still thinking “ahhh shwwwt what’s the sequence of operations?” Lol GREAT VIDEO CHRIS AS ALWAYS 👍. Let’s talk about them Water boilers & them gummies let’s get to work haha
I'm just a normal guy who likes these types of videos. So my question may be dumb, but does the nitrogen ruin the refrigerant?
If there's any mixture in a refer circuit, other than the refrigerant (because blended refrigerants are a thing), all kinds of fuckery starts happening. Jumping pressures, superheat and subcooling readings that make no sense and usually compressor failure.
Yeah, it ruins the PT characteristics of the refrigerant. I think you could get away with a very small amount but its usually just recovered then reclaimed/recycled or destroyed.
It wouldn't ruin it. R22 isn't a blend and the two would be separated. He bled it off so it's all good. If you left it in there, it will throw off compression and expansion properties of the refrigerant causing cooling issues and possible wear from messing with the oil traveling in the system.
With a blended refrigerant I'm not sure how it'd work out because the gases can separate so you'd ruin some of the characteristics by trying to bleed vapor. I think a specialized recovery machine would be used at that point to refine it back to a proper refrigerant.
A little excess heat shouldn't damage the filter drier, they usually just contain molecular sieves. They're zeolite adsorbant beads. They can be "recharged" and dried with heat of a few hundred degrees.
Impossible to find a schrader issue when you working on things STUFF happens. Any of the posters including me have done things much worse.
Hindsight is always 20/20 especially if your not the one that made the mistake
Good job saving the refrigerant
Very informative.
Years ago when I had high head pressure, I did the same thing to blead off air out of the refrigerant.
We all work under the assumption that the simple things just works and that the schrader valves just do that and at worst they leak.
But there's a movie quote from the movie "Under Siege 2" where it's stated "Assumption is the mother of all F-ups". That's one of the truest quotes from a movie. How successful you are is only measured by the end result, not the way you took.
In most conditions nitrogen is pretty inert and harmless, but you could probably get improper pressure readings if you have too much nitrogen in the system. At some stage it might be worth to consider a refrigerant recovery system that can purify the refrigerants, but I assume that's a pretty expensive investment.
I have seen those coremax valves go crooked, brazing in the suction or discharge lines on a compressor changeout, the heat can cook them real good. Can be tricky when they are 6" from braze points.
If myself or one of my tech's did that Id have to take responsibility for new refrigerant. I like the purging idea though!
Hey, I hate those carrier scraders! I don't change them I replace them! I use the regular ones. All my customers still want R-22! Even tho there are good drop in replacement gases. I've done the bleed off trick also too! I have polished a few turds in my time! I couldn't imagine doing work in your state!
If you are planing there will be chips😁 In my opinion you did a good job. Sometimes I'm in a similar situation and had to decide what kind of failure diagnostic strategy I use to find a fault. If my choice was suboptimal there will be a little bit more chips on the floor😁 There is a tomorrow everytime.
When I have a CLO lockout, I reset the power to see what will happen. Once I find power on X, I check for a call. If I have to, I place a jumper first and then test the system to see if it can run. If I can see evidence of a working compressor (as in having gas in the system to do work, such as a temp dropping on the suction line) then I know if I gauge up and see no pressure, it's those coremax valves again. I carry spares on the truck when I get approval to do the repair. Replacing the evap is a good move, but as you found out, the newer evaps don't fit. We had to hack up a 14 year old TME to fit the new part earlier this year. Carrier never got back to me when I told them about the issue, so I'm sure that they were told to not discuss this screwup. I stopped replacing orifices three years ago, because it does not always fix the problem. It may be a problem of thickened oil pooling in the evap or large plugs of wax after the orifice...I haven't taken one home to do an autopsy. The evaps go to the boss' house and are Company scrap. I will sometimes try heating them with pressure on the suction side and an open liquid line, and if that doesn't work, it's big bucks time. Oh, well. I didn't tell them to not use a nice Sporlan TEV. I already have two units lined up for evaps next cooling season. I just remind myself that I didn't design this junk.
Good Job Chris.
Completely ethical in my view. I believe if absolutely necessary you could've charged for new gas as well, but you did the best for this turd. Great job with these videos, much help.
We don't ever touch or use Coremax fittings around here. I believe they don't even accept regular hose fittings? Systems I see have coremax and regular service acsess fittings. Why mess with such BS fittings? Faster evacuation for little 5/10 ton units!?
Very foolish$$ for the engineering genius's who think we need two different access fittings right next to eachother when most times they can't even include just one!
Bigger Systems we pull vacuum through king valves and other types of full flow service valves. Why does Coremax exist is a good question
Excellent job on getting creative with recovering from your mistake though.
I've developed purging habits that probably are unessessary for fear of not wanting to get any air into a system.
One tip. If you think you might be in a vacuum before putting low side guage on then shut off system to give best chance of not hooking up on a vacuum that sucks in hose air.
CA does sound retarded. Less hassle to pay more to fix vs. replace
Never heard of such anywhere else
If you look right here we have a legend.
Well yeah, of course you're a legend, that's why we watch your content:)
Keep up the great videos!
I replace the CoreMax Cores, but I remove the whole center. I install a swivel tee w/ cores on both ports. Then Nylog & Torque everything down. If you need to service after, then you use VCRT’s.
i Like the way you solder, like me. use lots of heat and fosco solder, that makes NO leaks
That’s a bad part about those high flow cores. To much side to side play of the plunger. I have a video showing a O ring melted on the core also preventing the plunger from depressing. It happens!
My personal opinion is that you did what was best. I can't remember the phase diagram of nitrogen but I imagine it's boiling point under these pressures is lower than the refrigerant. You quoted them a full charge and were able to vent off the nitrogen for the most part. I used to work in automotive both as a mechanic and as a parts peddler and I always give a worse case scenario. Even if I don't think that's the problem I always let the customer know what the absolute worst is. It's always better to over quote and under charge than one quote and over charge.
Troubleshooting is always a process with infinite factors that can trip us up. Never dwell on mistakes, just keep trucking and figure it out.
My favorite torch tip, rose bud
We've all done things we'd wish we'd spent just 5 seconds longer thinking it through. My first boss said to me "never assume" That bit of advice bites me time and time again.. However blowing off the nitro and re-using the charge on the job is a personal choice. In this situation considering the customer had already approved new gas on the job I would have recharged with new, taken the old back to the yard and let it sit a while and vent off there . Once happy, that cylinder would go as van stock.. Either way it's no biggie and don't beat yourself up over it.Loved the drier falling off I'm usually swearing my head off by that point :-) . All back up and running = Great job
If the schrader is oddly depressed, will counseling help
Thanks for another great video Chris.
I think we all have done or will do that during our career. I did put nitrogen on top of the charge thinking it was flat, and it was the core depressor valve that was broken. We just have to laugh and move on. Sometimes we like to jump into conclusions because it look so obvious, old unit , leak are common, no pressure= we think it’s flat.
I've been told by my supervisor before that if you see that a unit low on gas or completely flat. Don't add nitrogen on top of the refrigerant you just add refrigerant, and search for leak which confused me because I thought that adding nitrogen on top was standard practice
Omg I just subscribed to your channel and I’m going through so much similar problems you’ve encountered with carrier it’s uncanny. I’m recently going through contractor chatting and with your video ima look into pressure sensors, also I to had a carrier that I thought was flat and yes why does carrier install those core max service ports?, I looked into that “special tool” and it was like 700.00
The clip of showing fixed orfice metering device was from your one of your old video 🤭
Awesome video Chris !
16:36 i think the "Artesian Style non-condensables hand purging" should cost extra!
Chillers do the same thing with a dedicated purge unit on top of the condenser. So this was an excellent use of your skill and understanding of how refrigerant works. This should be a presentation for hvac school.
20:16 okay, that got me XD
32:51 okay that's funny but I was just recently trained over a year ago that if I have to recover what I believe to be a system contaminated with non-condensables that I can do pretty much what you just did they do recommend stabilizing it over many hours as the only difference like in your shop with just the tank, but this is a real world situation and I like how you used the water to speed up the process and get the job done in a reasonable amount of time. I do believe that was also in training materials somewhere.
Yup, just checked my 608 prep manual and info is there. I found it in type 1 recovery requirements area
Oh Chris I was you would have come to a Starbucks in Ottawa to fix our ice machine I told them what I learned I told them the condenser could be iced up or réfringent leak it was not making ice at all.
Perfect fix 👍🏻
It was your error so you should have taken the hit even though it was a difficult situation. Great work as always.
Interesting perspective, I will discuss this on my livestream this evening 10/11/21 @ 5:PM (pacific) come over and check it out th-cam.com/video/Mf8BPexYVhA/w-d-xo.html
Nice Turbo cap in there... I can understand putting it in there for a temporary fix, but that is not a cheap fix leaving it there.
Like the blooper bro!👍🏻
🥃🥃🍺🍺🍺🍿🎯
I would have done exactly what you did on the refrigerant. We both know plenty of people that would charge for virgin refrigerant no matter what which is not a bad thing. I prefer to stick with OEM and not redesign a system.
It never occurred to me to purge non condensables like that but I’ve also never accidentally put nitrogen on top of r-22. Easy mistake to make though, I’ve also never seen both valves go bad like that either
I Think I would routinely discard any thing recovered. But that is why I watch the videos, hoping to understand the big picture better.
Just bad luck. That always happens to me late in Friday.
15:03 the valve pin bent to side just push it to center all good to go. i know because this also happen to me.
You are supposed to clean the refrigerate by running it through a filter dryer from a tank to another, if you are going to reuse refrigerate according to the EPA law.
EPA also says you can't take the old R22 and use it on another job the R22 suppose to stay with the same owner/system
you are awesome man , always loved your videos
Seeing as I have no experience with HVAC, I do find your videos very interesting and I'm learning alot.
General question: You showed that the carrier unit used two single phase contactors between lines 1, 2 and 3. Wouldn't it be more efficient to replace those two contactors with one 3-phase contactor that I've seen so many of the other units have? Or is just not possible/worth it?
Thanks for the videos, Chris, and keep up the great work!
That wouldn't work. The contactors each control separate devices by switching two of the three phases.
This fully opens the circuit, even though there's still a hot leg going to the motor, that energy has nowhere to go.
I do three phase work for my job often, and I would personally really prefer true three-phase contactors, but I understand why they went the less expensive route.
@@FerralVideo I see. Thank you for clarifying!
As for liability, you know that those valves are prone to going bad and not opening. You should have noticed they were faulty when you removed the caps. Luckily you saved the gas but I believe as an experienced tech you should have noticed the condition of the valves before connecting to them. Did you make a note of the time wasted and not bill for it?
I've wondered if it might be possible to save refrigerant gas mixed with a small amount of nitrogen (or possibly another non-refrigerant gas). Had it not worked out, I'm not sure I would have charged the customer for all new refrigerant. I might split/pro-rate it. (But take that for what it is from a largely "armchair" technician who doesn't do this as his primary source of livelihood.)
I caught what happened the first time, though I wasn't totally certain why.
On those coremax fittings how do you pull a vacuum since you can’t remove the scraper core what do you attract to it to depress the core
Your best bet is to use a core depressor I happen to use the appion core depressor
trutechtools.com/appion-cct14-core-control-tool.html
The link I sent is for trutechtools if you end up purchasing one do me a favor and use my offer code (bigpicture) one word at checkout to get a discount and in turn I get a commission
YOU MENTIONED VIBRATION ON UNITS , the Florida building that collapsed had 60 RTUs on it plus old concrete
Those were condensing units, not RTU's You can see several of them on top of the pile after the building came down.
@@arthouston7361 I was thinking in general terms , none the less I went to google earth re counted and it was twice as many then I thought not only was the vibration an issue but each fan is creating a downward force on the roof ( there was one large package unit the rest were splits )
8777 Collins ave Surfside Florida
IMO what you did is just fine. You looked after the customer and made sure there isn’t any appreciable amount of N.