Tool List- www.amazon.com/shop/acservicetech Support- www.patreon.com/acservicetech For those that are looking for the tools used in the videos: (Linked Below) Here is the Link for the Yellow Jacket Refrigerant Manifold Gauge Set used in the videos- amzn.to/2aenwTq Here is a link to Refrigerant hoses with valves used in the videos- amzn.to/2aBumVI Here is the Yellow Jacket Manifold Gauge Set including standard hoses- amzn.to/2vLVkV9 Here is the Yellow Jacket 4 Port Brute Manifold with Hoses- amzn.to/2BkuGIq Here is the Fieldpiece SMAN360 Digital Manifold Set- amzn.to/2BdoaD4 Here is the Fieldpiece SMAN460 Digital Manifold Set- amzn.to/2nB4Fe6 Here is the Compact Ball Valve Attachment for the end of the Refrigerant Hose- amzn.to/2KUisW8 Here is the Quick Disconnect 90 degree attachment for the end of the refrigerant hose- amzn.to/2MMtVcg Here is a link to the UEI DL389 Multimeter used in the videos- amzn.to/2xAdaJf Here is a link to the Imperial 535-C Kwik Charge Vaporizer for Charging Refrigerant- amzn.to/2wFHtBW Here is the link to the Fieldpiece ST4 Dual Temp Meter- amzn.to/2wc1ME3 Here is a link to the Digital Refrigerant Scale used in the videos- amzn.to/2b9oXYl Here is a link for RectorSeal Bubble Gas Leak Detector amzn.to/2ckWACn Other tool links can be found in the video description section. ACSERVICETECH is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon. Check out other videos on the HVACR topics of interest at- th-cam.com/channels/OZR-1IqsAer9wzlvFgb4mA.htmlplaylists?view_as=public If you want to support the ACSERVICETECH Channel and receive more HVAC content, check out www.Patreon.com/acservicetech
acservicetech thank you for the videos !!!! I have learn a lot with them ! Probably more than I did in school!!! If you had a hands on lab to simulate some of the problems and you have a like weekend seminar many will go !! Please keep doing what you doing you are doing a great job to the community!!!
Do you guys hire migrant workers bro I am from another country and willing to migrate to yours to dedicate myself and my time to work hard in the successful building of your Establishment
⭐️⭐️⭐️⭐️⭐️Great video Craig. So informative. I usually see vapor lines at 70 to 75 psi (R22) and 120 to 125 psi (R410A), more or less. I learned something on the saturated temp explanation and the pressure variances you gave. (60-80 & 105-140) Thank you.
I don't think you realize how many people you're helping by Doing videos and actually responding to comments a lot of people don't want to share their knowledge i've done installs but now I'm starting to get more into the service side of things and your videos have been a big help
@@acservicetechchannel good morning sir I m very happy to hear u. Your work is point to point clear. Sir some deep questions for u? In r32 do we trust in pressure or trust in sticker level on the mini air conditioner outdoor which told 650g gas in 1.5 ton ac? If the pressure which if have to follow? Because old system efficiency is less. Do i put some extra gas like 50g extra or less? If i put the extra gas amps go up? Indoor unit is down, outdoor unit is on roof. Gas pipe is 3.5 meter. Distance is less can i cut pipe and make 2 meter? Would i have to extra gas charging? And if the 30 min with vacuum with refrigerator compressor is it right vacuum? If the vacuum without vacuum pump is it ok? Can i re-vacuum the unit because now how can i remove the air from the system if vacuumed with refrigerator compressor? Now i have to vacuum with double stage vacuum pump? Or i have to out totally gas from the system and then again i vacuum with vacuum pump? Please tell me help me?
So first, when working with an empty system, you need to pressure test, oil blowout, vacuum with a VACUUM GAUGE, to verify that you are below 500 microns, then the 10 minute standing vacuum test, then break the system with refrigerant from the system or liquid refrigerant into the liquid line which is weighed in. If there is air in the lines mixed with the refrigerant, it needs to be recovered to specified level before starting over, thanks
man you are not only helping people with tech problems ,in my case you have help put food on the table for my kids and when I was starting out I could not really learn from other videos. you way of teaching is five star ! on point .and as the old proverb goes you give some one some bread you feed them for a day .teach them to make bread you feed them for life .thank you so much for all of your help you videos are so good you never have to ask a question its already covered
As a former instructor and soon to be, instructing again, I can appreciate the clarity and ease of understanding, just what this video explains...Will made, great orating and I will use this method, if not the video itself...My thanks to the gent that made it...To people that want future employment...Learn the trades.
I just want to thank you for spending your time teaching people like me that are hungry for knowledge like yours you have a big heart I’ve subscribed little while back and enjoy very much the videos thanks again
I watched this video more than 5! Time but every time I watch it I’m learning something new and very helpful thanks. Because I run to an ac with r22 refrigerant and has high pressure on high side and was afraid if I did something wrong to the system after I watch this video again I understand it was because it small condenser with low sears. Thanks again
I've been working with ACs for the past 4 years but i am really wanting to learn about super heat since the ACs at my job use a piston, thanks for the detailed info, one of the best vids I've seen.
Thanks for sharing your extensive knowledge. You would likely enjoy the details of wide-body jet airconditioning systems. Since the OAT varies from say 115F when taxiing out for takeoff in, say, Phoenix to -41F OAT at 39,000 feet cruise altitude, the aircond "packs" work to cool the cabin at low altitudes but must function as "heaters" when it's 41-deg below zero at cruise altitude. The most remarkable characteristic about these a/c "packs" is that they do not require any charge of refrigerant. In fact, there is NO refrigerant in the system except fresh air. The system takes (bleeds") high pressure air from the engines to drive a compressor (turbine) that inducts outside air, compressing it, then cooling it in the slipstream, then allowing it to expand again. As you know, this cycle creates a powerful thermal exchange. Then, the cold expanding exhaust is simply piped into the aircraft. By controlling how quickly this volume of air is injected into the cabin, the aircraft can be "pressurized" as well. The fact that no airconditioning refrigerant must be added means that the systems are extremely reliable and the performance doesn't vary since the compressor is a rotary turbine, not a rotary piston whose efficiency is affected by wear. Thanks again for your videos. I would enjoy sitting down with you to ask you questions. TH-cam is the next best thing. Good luck sir.
Thanks for the awesome, detail filled learning experience for everyone. Thank you for taking the time to write it. Are you a pilot, engineer, or mechanic?
Great Video. Very informative and not alot of wasted time giving shout outs to friends or talking about unrelated topics. You can tell when someone does their homework beforehand. This is exactly the type of video I'm looking for when searching for info on youtube. TH-cam needs more folks like you. Thanks a bunch!!!!
this make it easier for me to comprehend the science behind it.. i rewind constantly to make sure i understand.. although i dont understand SEER measurements yet..
It has to do with how efficient the unit's energy transfer is and therefor electrical energy used to transfer the heat energy. In reference to an outdoor unit, the higher the seer, the larger the surface area of the coil is. The indoor evaporator coil would need to be larger as well to attain a higher seer rating, thanks
I have a question. Our AC Unit was checked and we were told that it was working great. It was a model from 2008. However, by the following day our unit was no longer cooling and the refrigerant was completely empty. We also had water near our furnace from the evaporator coil. I requested the report from the company and these are the numbers that were listed. High Side Pressure=210, High Side Temp=105, Low Side Pressure=70, Low Side Temp=38. Were these readings ok? Or was it indicative of a problem?
I have a question. Let's say in NC the ambient temperature outside is 80 degrees and you are using R-410A refrigerant. What should my high side and my lowside pressures be? Second question if you charge the unit with a subcooling of 12 because that is what it calls for will you still have the same subcooling at 95 degrees in the summer?bAnd what will your high side and low side pressure s be?
Is it normal for head pressure to swing upwards of 70-100psi while running? On a 70 degree day. Unit is around 300psi high side and swings up to 380-400 and then back down. Low side is about 125psi
If a system at sea level has a standing pressure of 14.7 psig on a standard gauge does that mean it is completely void and anything less is technically under vacuum/ open to moisture contamination?
Check the gauge's saturation temperature for each refrigerant against a PT chart. At one time I found one set of gauges where the R-410a temperatures did not match the pressure against a PT chart. Always verify your equipment is correct.
Hi craig. In ductless Minisplit , refrigerant is available both indoors and outdoors. So standing pressure (when compressor is not on) will correspond to Indoor temperature or outdoor temperature or something in between and why??
question please ,,i am a retired tech from way back i never got to work with 410A BUT ! i have enough r22 in my garage to charge a new system now having said that ,,,,,have you ever took a 410A , change the oil ,tvv, to make it work with r22 ? can i do that ? or have you heard of someone that did this or maybe you ? ,,,,,,thanks for your opinion
what about roof top package type units???....i was told do not worry about subcool or superheat method and just charge by pressure...could not find a subcool rating anywhere ..has txv valve
Hi question: what caused the low press pipe condensor outside frosting and hi press pipe cold on the evaporator side ( when you touch it) ? this happens when The AC has been running over 10 hours then temperature house stuck at 24.5 degrees C then the indoor house turning hot again? thank you
Hi i have a Daikin 2HP mini split installed in my house. It has R22 refrigerant. Temps at my place can get upto 110F during peak noon 1-3pm. Cooling is reduced upto 35% when its peak heat around 100-110F in evenings or night temps are around 80-85F it works cold. And the outdoor unit is exposed directly to sunlight and it has around 12 meters of copper piping installed. The low side is 70 psi when outside temp was around 100F
Is this an inverter style or single speed compressor? Do you have an indoor temp diff between the return air and supply air of 18 degrees when it is 80-90 degrees outside?
Does it say a rated subcooling on the rating plate? Is there a charging guide on the back side of the shroud. It likely has a txv on the outside and yes if it is a single speed then you can check the charge with subcooling for txv units and superheat for pistons. Subcooling of usually 8-12 degrees for txv equipped, single speed, comfort cooling units without a stated txv rating. thanks
acservicetech its plate says R22 charge 1.5kg. If the outdoor unit is directly exposed to sunlight heat of around 100F it will effect the cooling of AC and make compressor run more harder
Hi amazing video by the way. At the end when you talking about the unit being 300 psi being too hot due to condenser failing, could be a clogged dryer or piston too.
Should a unit be running when checking levels on a manifold or is the reading the same if off power? I’m getting a reading of 220 psi on my mini split while the unit is off.
Thank you for your videos. I too learn more than I did in school. My question is with a r22 system in Las Vegas 115 outside what would I expect the temperature to be in middle of condenser coil? It is a10 seer split system. Thanks
Your videos are great man have really learned a lot from the way you teach things and make them easier to understand. How do you know what the head pressure should be for an R22 and 410A system if the outdoor coil is clean and the ambient is around 70 degrees F. I was taught anything above 70F, add 30F and that should be your saturated condensing temperature. So if it’s 80 degrees ambient add 30 degrees which gives you 110F. See what pressure that corresponds to using a pt chart for a given refrigerant and that should be your pressure. Is that a good way to determine what your head pressure should be
What you are describing is that old ambient plus 30 rule of thumb. We use superheat and subcooling for efficiency and compressor safety. That was a rule that got you close on old 10 seer r22 units. Look up "acservicetech subcooling and superheat" I also have everything explained in detail step by step in the book at acservicetech.com thanks!
It depends on a few factors but sometimes you wont see the suction gauge go up much because it depends on the metering device and some other factors or you wont be able to charge the refrigerant much because of the devices in the line. Otherwise, most of the time the suction and discharge gauges will reach equilibrium once the refrigerant settles. Alot of times you have to charge as much as you can with the system off then turn the system on so you can finish putting in the rest of the charge because you need a better pressure differential. Ive even had it where i can barely put in refrigerant while the system is off and i had to manually turn on the compressor or bypass the low suction pressure sensor because i couldnt get enough refrigerant in the system for it to stay on long enough because it kept tripping on low suction pressure
I wonder if TUMP could possibly reverse the ridiculous ban on R-22? All the millions wasted on overpriced R-22 and its inferior replacements. Not to mention a lot of older units replaced with junk new ones that will leak in a year or less due to garbage "high efficiency" coils combined with the excessive pressures of 410a.
I have 2010 (13 years old) Trane 5 ton 14 SEER heat pump, TXV. Label states the following: R410A, 10 degree subcooling, comp RLA 26.4, Design PSI HIGH 480 LOW 480. Anyone know what "Design PSI HIGH 480 LOW 480" means? It's not cooling very well so I took pressures today when it was 111 degrees outside. Readings were High 510 PSI (136 degrees saturation), liquid line 118 degrees. Low 135 PSI (46 degree saturation), vapor line 74 degrees. That's 18 degrees Subcooling and 28 degrees SuperHeat. Not sure I truly trust my line temps since I'm using an inexpensive thermocouple. I may need to invest in the Fieldpiece thermocouple you use in your videos. How does high ambient temps affect pressures and line temps? If using approach method, my liquid line is 7 degrees above ambient but my pressure should be closer to 480, not 510 PSI. I also checked my compressor amps at about 23 amps. RLA is 26.4. I'm going to check the pressures again in the morning when it's closer to 90 degrees.
I just started up my own little system but its a medium temp system . Now am confused my friend says it is under changed and I know it is. My high side is at 151 psi and my low side is at 42 Psi How is it that am getting 41F across my coil and my suction temp is at 53F for the compressor. All I know if for my system the evaporator coil needs to be under 40F say about 30F to 35F. Maybe I just need to keep adding gas but when I do my compersser shuts off on high pressure. I am confused it is water cooled as well.
Awesome channel! There is so much bad information out there on this topic so thank you for teaching us! Btw how are window and portable units able to operate at 300psig low / 520psig high (R410a). I’ve been looking everywhere for an answer and can’t find one. They are usually completely sealed systems and don’t have service ports. But even if you install a port, how would you fill it to 300psig?! It seems like they can’t be repaired. There is usually a sticker with the specs on the side of the unit and that’s where I’m getting these numbers from.
Yes that is the max design pressure for sure, they operate the same as other r410a fixed orifice systems and you would mout the port on the low pressure side to check the superheat since it has a capillary tube as the metering device, thanks
Kind of. The system name plate will usually tell you the normal charge in the system (in the US it will say 5lbs of R22 for example) and then since you know what normal operating should be, you can kind of guess. If the system is operating at half the normal pressures then you would be somewhere around 2.5lbs of refrigerant based on the example above. But don’t forget that any split system with more than 20ft of line set you have to add a few ounces per every few feet of extra line set. I cant remember the exact numbers but yea
We have a min of 95F cond temp on all systems so you're going to have a low of that on 22 or 410 systems, so 22 shouldn't be any lower than 190psi and 410 280psi, any lower and the system needs head pressure controls or it will crash, you won't be able to maintain control of the low side and you might slug the compressor, variable speed equip might be the exception.
Do you know why on carrier heat pumps only why you have to get high side pressure in heating mode on the larger hot discharge line service port and if you check the 3/8 service port pressure it will be close to your suction pressure? On every other manufacturer you get high side pressure on the 3/8 service port in heating and cooling. Thanks!
Brian, That is because they have the metering device in the piston chamber right before your port when the subcooled liquid is flowing from the indoor coil toward the outdoor coil. The piston is right under the nut. If the port were 3 inches closer to the indoor coil, it would be high pressure subcooled liquid. You are reading low pressure liquid with 20 percent flash gas at that port because it is right after the metering device in heat mode. Other manufacturers place their piston chamber inside the outdoor unit so it is further downstream, thanks
AC Service Tech LLC that makes sense I just would think the hot discharge gas pressure would be too high because of the increased temp / pressure created from the compressor to be an accurate high side pressure
Are you talking about following a manufacturer charging procedure for a heat pump in heat mode because other than that, we can't really check a charge in heat mode due to not knowing how much refrigerant is in the accumulator. We are stuck with total weight procedure or reducing condensor airflow to raise high side sat temp in cooling mode but it would need to be 38 degrees or higher ambient temp for that method, thanks
Nice video, you're a good teacher. bought a new house, and trying to evaluate the ac system. Nordyne 3 1/2 ton 1600 sq. ft house. the best my low side ever gets is at 11AM Low:92 r22 ring: 52. but at 4 in the after noon the system wont shut off at 78 degrees in the house. So low on 22? compressor going bad? High on 22? I've cleaned both sets of coils, evaporator was really bad. Advice?
Hey David, I would need to know if you have a txv or fixed orifice such as a piston or capillary tubing as the metering device in order to answer the question. Then I would need high and low pressures, superheat, subcooling, outdoor temp and indoor wet bulb temp. We don't go by pressures only in order to check a charge, thanks
Something I can't seem to understand is if the temperature outside is cool like 70s your suction pressure can seem low like at a 30-32 degree saturation but be perfectly fine. Like If its 70 degrees in the house my low side sat temp is like 30.. how does this work? Your videos help me in my career. I'm out here in FL as well thanks
If it is below 32 degrees sat temp then it would be freezing so that wouldn't be good. That would mean either low airflow, low refrigerant charge, liquid line restriction or low temperature inside the building. The evaporators for air conditioning are designed to run at around 40 degrees. That could mean anywhere between 32 and 55 degrees depending on the indoor temp crossing the coil and the outdoor temp. It has to be low enough to get the humidity in the building to condense and drip into the pan and low enough to absorb heat efficiently. Keep watching the videos. Look up "acservicetech superheat playlist" to learn more and check out the ones with the evap coil in the thumbnail, thanks
@@acservicetechchannel right I know below 32 degrees it's freezing.. however if the indoor temp is cold I notice my sat temp is very low BUT there would be no issues at all. Just confuses me. Thank you
Thank you for your video, guru. My AC is RUDD UACC-036JAS, R22 refrigerant system, it has refrigerant leakage, the Tech refilled R22 to Low Pressure at about 62 psi, High Pressure is 220 psi, is it ok for cooling? but I feel it is slow to make rooms cool. What is the best psi of Low Pressure for my AC? Thanks.
he would need to check it with superheat or subcooling but the refrigerant will eventually leak out again. He would need to find and fix the leak. You could also check for 18-21 degree temp decrease between the return air and supply air to verify it is working correctly, thanks
Acservicetech this is really but really a exelente video man...can you make some more videos like this one explaining the pressures and the simtoms or problems like you did on this one...we really need videos like this one well I need videos like this one.
Thank you for your videos. I have a question about the "expected pressure" on the high side, can we take the SEER rating, refrigerate type and the outside temperature and add a constant value to get the expected high side pressure? So for a example a R22 on a 85 degree day for a SEER 13 would mean the pressure should reflect 85 + 20 = 105 F. Then covert 105F on a PT chart?
Kow the are . Diffwrnce in temperraure of of out and room air and u factor the heat leakge rhrufh wall . Cilling and floor per hour canbw calculated using the following equation .. Heat leakge =ufactor xtemperature difference =uxAxTD (u=factor -Btus =area -squre feet Td=tempreaature difference -°f.
In the same panel as evaporator coil or right outside the evap coil usually unless it is a fixed orifice or exv. Those are usually at the condenser. But they are all on the liquid line going to the evap coil
So I charge refrigerators all the fine but I’m gonna be charging my RV AC tomorrow and it’s R410a. I dnt believe I have a way of measuring the 22oz charge. Do I just charge it running till I get around 110 psig on the low side ?
We usually use a digital scale for systems like that but you could check the type of metering device such as if it has a piston and use the superheat method likely, thanks
You mentioned that things are different in an inverter type system. Can you explain that more? I am seeing about 75psig on the low side of a R410a mini-split during operation and trying to figure out if that is somehow normal or if there is actually a leak.
Mini split manufacturers don't give us superheat or subcooling guidelines but just the total weight procedure for inverter type units unfortunately however the low side sat temp should not be below 32 degrees, thanks
My low side pressure reads 200+. When I add 410a, it goes even higher. High side reads 285. No idea what’s going on. It’s like it’s not taking my refrigerant.
Tool List- www.amazon.com/shop/acservicetech
Support- www.patreon.com/acservicetech
For those that are looking for the tools used in the videos: (Linked Below)
Here is the Link for the Yellow Jacket Refrigerant Manifold Gauge Set used in the videos- amzn.to/2aenwTq
Here is a link to Refrigerant hoses with valves used in the videos- amzn.to/2aBumVI
Here is the Yellow Jacket Manifold Gauge Set including standard hoses- amzn.to/2vLVkV9
Here is the Yellow Jacket 4 Port Brute Manifold with Hoses- amzn.to/2BkuGIq
Here is the Fieldpiece SMAN360 Digital Manifold Set- amzn.to/2BdoaD4
Here is the Fieldpiece SMAN460 Digital Manifold Set- amzn.to/2nB4Fe6
Here is the Compact Ball Valve Attachment for the end of the Refrigerant Hose- amzn.to/2KUisW8
Here is the Quick Disconnect 90 degree attachment for the end of the refrigerant hose- amzn.to/2MMtVcg
Here is a link to the UEI DL389 Multimeter used in the videos- amzn.to/2xAdaJf
Here is a link to the Imperial 535-C Kwik Charge Vaporizer for Charging Refrigerant- amzn.to/2wFHtBW
Here is the link to the Fieldpiece ST4 Dual Temp Meter- amzn.to/2wc1ME3
Here is a link to the Digital Refrigerant Scale used in the videos- amzn.to/2b9oXYl
Here is a link for RectorSeal Bubble Gas Leak Detector amzn.to/2ckWACn
Other tool links can be found in the video description section.
ACSERVICETECH is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.
Check out other videos on the HVACR topics of interest at- th-cam.com/channels/OZR-1IqsAer9wzlvFgb4mA.htmlplaylists?view_as=public
If you want to support the ACSERVICETECH Channel and receive more HVAC content, check out www.Patreon.com/acservicetech
acservicetech thank you for the videos !!!! I have learn a lot with them ! Probably more than I did in school!!! If you had a hands on lab to simulate some of the problems and you have a like weekend seminar many will go !! Please keep doing what you doing you are doing a great job to the community!!!
Great idea frontiermarvin71! Thanks
Do you guys hire migrant workers bro I am from another country and willing to migrate to yours to dedicate myself and my time to work hard in the successful building of your Establishment
ty
⭐️⭐️⭐️⭐️⭐️Great video Craig. So informative. I usually see vapor lines at 70 to 75 psi (R22) and 120 to 125 psi (R410A), more or less. I learned something on the saturated temp explanation and the pressure variances you gave. (60-80 & 105-140) Thank you.
I don't think you realize how many people you're helping by Doing videos and actually responding to comments a lot of people don't want to share their knowledge i've done installs but now I'm starting to get more into the service side of things and your videos have been a big help
That's great to hear Matthew, thank you!
Thank you so much for your time helpping us to understanding that..
@@acservicetechchannel good morning sir
I m very happy to hear u.
Your work is point to point clear.
Sir some deep questions for u?
In r32 do we trust in pressure or trust in sticker level on the mini air conditioner outdoor which told 650g gas in 1.5 ton ac? If the pressure which if have to follow? Because old system efficiency is less. Do i put some extra gas like 50g extra or less? If i put the extra gas amps go up? Indoor unit is down, outdoor unit is on roof. Gas pipe is 3.5 meter. Distance is less can i cut pipe and make 2 meter? Would i have to extra gas charging? And if the 30 min with vacuum with refrigerator compressor is it right vacuum? If the vacuum without vacuum pump is it ok? Can i re-vacuum the unit because now how can i remove the air from the system if vacuumed with refrigerator compressor? Now i have to vacuum with double stage vacuum pump? Or i have to out totally gas from the system and then again i vacuum with vacuum pump?
Please tell me help me?
So first, when working with an empty system, you need to pressure test, oil blowout, vacuum with a VACUUM GAUGE, to verify that you are below 500 microns, then the 10 minute standing vacuum test, then break the system with refrigerant from the system or liquid refrigerant into the liquid line which is weighed in. If there is air in the lines mixed with the refrigerant, it needs to be recovered to specified level before starting over, thanks
I agree your videos are absolutely awesome your a great teacher
man you are not only helping people with tech problems ,in my case you have help put food on the table for my kids and when I was starting out I could not really learn from other videos. you way of teaching is five star ! on point .and as the old proverb goes you give some one some bread you feed them for a day .teach them to make bread you feed them for life .thank you so much for all of your help you videos are so good you never have to ask a question its already covered
Thanks a lot David. I really appreciate your comment! Awesome!
Thanks Jesus/God bless. More than two years I'm checking videos on TH-cam to know about that. You are the only one who give very good informations.
Thank you Di Si, Praise the Lord!
i went to school,but it seems that ur being more helpful than the school, thanks man nd keep doing such of great job I really grateful
Thanks a lot William! I am glad the videos are helping that much!
As a former instructor and soon to be, instructing again, I can appreciate the clarity and ease of understanding, just what this video explains...Will made, great orating and I will use this method, if not the video itself...My thanks to the gent that made it...To people that want future employment...Learn the trades.
Thanks a lot Vern! Enjoy Teaching!
You're detailed videos are hands down the best I've seen on You Tube. Great job !!!
Thank you very much dantinas!
thank you Doctor. I am saturated now, just a homeowner not an installer will watch a couple more times, thank you for the video.. thumbs up.
Ha Ha thanks!
I just want to thank you for spending your time teaching people like me that are hungry for knowledge like yours you have a big heart I’ve subscribed little while back and enjoy very much the videos thanks again
I appreciate that very much Silvio!
This video has given me more understanding in reading the gauges and what can be going on
I watched this video more than 5! Time but every time I watch it I’m learning something new and very helpful thanks. Because I run to an ac with r22 refrigerant and has high pressure on high side and was afraid if I did something wrong to the system after I watch this video again I understand it was because it small condenser with low sears. Thanks again
There are many things I learned on your videos. Hard to explain. Thanks. God bless you and your family.
Thanks for letting me know! May the Lord Bless You Too Fortino!
My 19 year old R-22 system is dying. 2 ton unit. Trying to get an idea how to change to the new and best stuff. Nice job!
I've been working with ACs for the past 4 years but i am really wanting to learn about super heat since the ACs at my job use a piston, thanks for the detailed info, one of the best vids I've seen.
Thanks Theo! Look up "acservicetech superheat playlist" for more!
Thanks for sharing your extensive knowledge. You would likely enjoy the details of wide-body jet airconditioning systems. Since the OAT varies from say 115F when taxiing out for takeoff in, say, Phoenix to -41F OAT at 39,000 feet cruise altitude, the aircond "packs" work to cool the cabin at low altitudes but must function as "heaters" when it's 41-deg below zero at cruise altitude. The most remarkable characteristic about these a/c "packs" is that they do not require any charge of refrigerant. In fact, there is NO refrigerant in the system except fresh air. The system takes (bleeds") high pressure air from the engines to drive a compressor (turbine) that inducts outside air, compressing it, then cooling it in the slipstream, then allowing it to expand again. As you know, this cycle creates a powerful thermal exchange. Then, the cold expanding exhaust is simply piped into the aircraft. By controlling how quickly this volume of air is injected into the cabin, the aircraft can be "pressurized" as well. The fact that no airconditioning refrigerant must be added means that the systems are extremely reliable and the performance doesn't vary since the compressor is a rotary turbine, not a rotary piston whose efficiency is affected by wear. Thanks again for your videos. I would enjoy sitting down with you to ask you questions. TH-cam is the next best thing. Good luck sir.
Thanks for the awesome, detail filled learning experience for everyone. Thank you for taking the time to write it. Are you a pilot, engineer, or mechanic?
Retired, flew 40 years. Thanks again for your stellar videos.
Great Video. Very informative and not alot of wasted time giving shout outs to friends or talking about unrelated topics. You can tell when someone does their homework beforehand.
This is exactly the type of video I'm looking for when searching for info on youtube.
TH-cam needs more folks like you. Thanks a bunch!!!!
Thanks a lot Robert!
Very knowledgeable video you helping a lot of technician out there
I appreciate that!
All I am going to say, "THANK YOU" you do know what you are talking about.
Thanks Cesar! Our book goes into great detail about all the methods, false methods, troubleshooting and much more, thanks!
Thanks for your videos just finished trade school I started doing side jobs thanks
Really good explanation!!!
this make it easier for me to comprehend the science behind it.. i rewind constantly to make sure i understand.. although i dont understand SEER measurements yet..
It has to do with how efficient the unit's energy transfer is and therefor electrical energy used to transfer the heat energy. In reference to an outdoor unit, the higher the seer, the larger the surface area of the coil is. The indoor evaporator coil would need to be larger as well to attain a higher seer rating, thanks
Excellent coverage of condenser and evaporator pressures for R22 and R410. Thanks for the info!
Glad to help!
Thank you for making amazing videos. Very much appreciate the time you put into them. They are to the point, extremely well done. Thanks!
Thank you very very much Ken!
Really appreciate you and this channel!!! Love you man. I bought your book!!
Awesome, thanks for letting me know!!!
You are great easy to understand and most important pro technician qualified..to do the job.thanks for sharing your knowledge..is power..
Thanks Ronald!
Great Video and SOLID explanation!!! Thank You!
Glad you enjoyed it!
Great demonstration and easy to understand, thank you!
Glad it was helpful!
I have a question. Our AC Unit was checked and we were told that it was working great. It was a model from 2008. However, by the following day our unit was no longer cooling and the refrigerant was completely empty. We also had water near our furnace from the evaporator coil. I requested the report from the company and these are the numbers that were listed. High Side Pressure=210, High Side Temp=105, Low Side Pressure=70, Low Side Temp=38. Were these readings ok? Or was it indicative of a problem?
Thank you for making these videos, I am an installer transitioning to service Tech
Hey bro I appreciate your channel it's helping us to be better at our craft.
Thanks Fernando!
I have a question. Let's say in NC the ambient temperature outside is 80 degrees and you are using R-410A refrigerant. What should my high side and my lowside pressures be? Second question if you charge the unit with a subcooling of 12 because that is what it calls for will you still have the same subcooling at 95 degrees in the summer?bAnd what will your high side and low side pressure s be?
Thank you explaining this. Great video.
My pleasure!
What is the max pressure required for an inside evaporator. My evaporator has 400 psig. Can I use it for R-410A after flushing out the r-22?
Is it normal for head pressure to swing upwards of 70-100psi while running? On a 70 degree day. Unit is around 300psi high side and swings up to 380-400 and then back down. Low side is about 125psi
Thank you for your information
So nice of you
I love watching these videos when I feel like my teacher didn't completely explain it. I guess I should read more out of my book also
Great videos
Yeah, I'm not sure the book will give you all the ins and outs but more of just the premise with a couple of examples. Thanks Michael!
Well explained. So helpful.
Great job and video
Glad you enjoyed it
Excellent video 👍
If a system at sea level has a standing pressure of 14.7 psig on a standard gauge does that mean it is completely void and anything less is technically under vacuum/ open to moisture contamination?
Check the gauge's saturation temperature for each refrigerant against a PT chart. At one time I found one set of gauges where the R-410a temperatures did not match the pressure against a PT chart. Always verify your equipment is correct.
I found that once too. That was an interesting one! Always check
Your having a huge impact in the industry. I bought your book.
Thank you for your support!
Thanks for this video bro! it helps a lot.
Glad to hear it!
Great videos watched just this one about five times haha
Hi craig. In ductless Minisplit , refrigerant is available both indoors and outdoors. So standing pressure (when compressor is not on) will correspond to Indoor temperature or outdoor temperature or something in between and why??
question please ,,i am a retired tech from way back i never got to work with 410A BUT ! i have enough r22 in my garage to charge a new system now having said that ,,,,,have you ever took a 410A , change the oil ,tvv, to make it work with r22 ? can i do that ? or have you heard of someone that did this or maybe you ? ,,,,,,thanks for your opinion
Have you ever tried adding PAO oil to a r22 system? All the data I've seen is that it's compatible with mineral oil.
Enjoy all the videos.
Thanks Nor-Cal, I appreciate what your efforts as well!
Thank you for your videos. Very easy to understand and very informative.
Thanks Eduard!
what about roof top package type units???....i was told do not worry about subcool or superheat method and just charge by pressure...could not find a subcool rating anywhere ..has txv valve
Very good and informative video!
Hi question: what caused the low press pipe condensor outside frosting and hi press pipe cold on the evaporator side ( when you touch it) ? this happens when The AC has been running over 10 hours then temperature house stuck at 24.5 degrees C then the indoor house turning hot again? thank you
thank you. for passing on this information and teaching us about hvac
Thanks redd!
Hi i have a Daikin 2HP mini split installed in my house. It has R22 refrigerant. Temps at my place can get upto 110F during peak noon 1-3pm. Cooling is reduced upto 35% when its peak heat around 100-110F in evenings or night temps are around 80-85F it works cold. And the outdoor unit is exposed directly to sunlight and it has around 12 meters of copper piping installed. The low side is 70 psi when outside temp was around 100F
Is this an inverter style or single speed compressor? Do you have an indoor temp diff between the return air and supply air of 18 degrees when it is 80-90 degrees outside?
Its single speed R22 split.
Does it say a rated subcooling on the rating plate? Is there a charging guide on the back side of the shroud. It likely has a txv on the outside and yes if it is a single speed then you can check the charge with subcooling for txv units and superheat for pistons. Subcooling of usually 8-12 degrees for txv equipped, single speed, comfort cooling units without a stated txv rating. thanks
acservicetech its plate says R22 charge 1.5kg. If the outdoor unit is directly exposed to sunlight heat of around 100F it will effect the cooling of AC and make compressor run more harder
Absolutely, if it were installed in the shade it certainly would be better as long as long as air flow was not cut off, thanks
Hi amazing video by the way. At the end when you talking about the unit being 300 psi being too hot due to condenser failing, could be a clogged dryer or piston too.
Should a unit be running when checking levels on a manifold or is the reading the same if off power? I’m getting a reading of 220 psi on my mini split while the unit is off.
What about high outdoor temperature and low wet bulb like in the south west?
Amazing your channel is the best!!!
Thank you for your videos. I too learn more than I did in school. My question is with a r22 system in Las Vegas 115 outside what would I expect the temperature to be in middle of condenser coil? It is a10 seer split system. Thanks
Your videos are great man have really learned a lot from the way you teach things and make them easier to understand. How do you know what the head pressure should be for an R22 and 410A system if the outdoor coil is clean and the ambient is around 70 degrees F. I was taught anything above 70F, add 30F and that should be your saturated condensing temperature. So if it’s 80 degrees ambient add 30 degrees which gives you 110F. See what pressure that corresponds to using a pt chart for a given refrigerant and that should be your pressure. Is that a good way to determine what your head pressure should be
What you are describing is that old ambient plus 30 rule of thumb. We use superheat and subcooling for efficiency and compressor safety. That was a rule that got you close on old 10 seer r22 units. Look up "acservicetech subcooling and superheat" I also have everything explained in detail step by step in the book at acservicetech.com thanks!
AC Service Tech LLC Thanks, I really appreciate the info and your videos have helped me tremendously throughout my apprenticeship
Thank you Leo !and Acservicetech! you guys are awsome!
Thanks Alex!
have purchased a 5# tank of R410A for top up of unit. Tech says I need a valve to regulate pressure from tank. ???? Enjoy your blog...
Great video good easy explanation I found more information in this video thank you
What should the blue/low guage read when re-filling with R22? This would be in a constant temp climate like Miami of about 85 deg F.
It depends on a few factors but sometimes you wont see the suction gauge go up much because it depends on the metering device and some other factors or you wont be able to charge the refrigerant much because of the devices in the line. Otherwise, most of the time the suction and discharge gauges will reach equilibrium once the refrigerant settles. Alot of times you have to charge as much as you can with the system off then turn the system on so you can finish putting in the rest of the charge because you need a better pressure differential. Ive even had it where i can barely put in refrigerant while the system is off and i had to manually turn on the compressor or bypass the low suction pressure sensor because i couldnt get enough refrigerant in the system for it to stay on long enough because it kept tripping on low suction pressure
top of the line video, beautifully simplified explanation of the gages, best one I have seen yet,
thank you much
Thanks purrungas2012!
I wonder if TUMP could possibly reverse the ridiculous ban on R-22? All the millions wasted on overpriced R-22 and its inferior replacements. Not to mention a lot of older units replaced with junk new ones that will leak in a year or less due to garbage "high efficiency" coils combined with the excessive pressures of 410a.
Thanks for the info. It really does help a lot. Thanks for taking the time to make the videos.
Great to hear Keith! Thanks
Can i use an r22 guage to measure pressure on an r410a system
I have 2010 (13 years old) Trane 5 ton 14 SEER heat pump, TXV. Label states the following: R410A, 10 degree subcooling, comp RLA 26.4, Design PSI HIGH 480 LOW 480. Anyone know what "Design PSI HIGH 480 LOW 480" means? It's not cooling very well so I took pressures today when it was 111 degrees outside. Readings were High 510 PSI (136 degrees saturation), liquid line 118 degrees. Low 135 PSI (46 degree saturation), vapor line 74 degrees. That's 18 degrees Subcooling and 28 degrees SuperHeat. Not sure I truly trust my line temps since I'm using an inexpensive thermocouple. I may need to invest in the Fieldpiece thermocouple you use in your videos. How does high ambient temps affect pressures and line temps? If using approach method, my liquid line is 7 degrees above ambient but my pressure should be closer to 480, not 510 PSI. I also checked my compressor amps at about 23 amps. RLA is 26.4. I'm going to check the pressures again in the morning when it's closer to 90 degrees.
so critical and helpful information, thank you
Glad it was helpful!
I just started up my own little system but its a medium temp system . Now am confused my friend says it is under changed and I know it is. My high side is at 151 psi and my low side is at 42 Psi How is it that am getting 41F across my coil and my suction temp is at 53F for the compressor. All I know if for my system the evaporator coil needs to be under 40F say about 30F to 35F. Maybe I just need to keep adding gas but when I do my compersser shuts off on high pressure. I am confused it is water cooled as well.
Good video
Awesome channel! There is so much bad information out there on this topic so thank you for teaching us! Btw how are window and portable units able to operate at 300psig low / 520psig high (R410a). I’ve been looking everywhere for an answer and can’t find one. They are usually completely sealed systems and don’t have service ports. But even if you install a port, how would you fill it to 300psig?! It seems like they can’t be repaired. There is usually a sticker with the specs on the side of the unit and that’s where I’m getting these numbers from.
Or perhaps it’s the maximum pressure the unit is built for..... yeah probably that. :)
Yes that is the max design pressure for sure, they operate the same as other r410a fixed orifice systems and you would mout the port on the low pressure side to check the superheat since it has a capillary tube as the metering device, thanks
Thank you for sharing your knowledge and experience .
Glad to help Haben!
You should add that a technician must verify the correct volume , CFM, of airflow before charging a system.
Yes, thanks
Absolutely, they must be done before checking the charge. Thanks Gary!
Is there a way to approximate how low in refrigerant a system may be using the gauges? Thanks. Love the channel.
Kind of. The system name plate will usually tell you the normal charge in the system (in the US it will say 5lbs of R22 for example) and then since you know what normal operating should be, you can kind of guess. If the system is operating at half the normal pressures then you would be somewhere around 2.5lbs of refrigerant based on the example above. But don’t forget that any split system with more than 20ft of line set you have to add a few ounces per every few feet of extra line set. I cant remember the exact numbers but yea
hello ,i hook the low side but needle not move can you tell me why? thank you
Nice one, Craig. Lot's of good info here. Thanks!
Thanks Jack, hope all is well!
This is great thanks for your help 👍
We have a min of 95F cond temp on all systems so you're going to have a low of that on 22 or 410 systems, so 22 shouldn't be any lower than 190psi and 410 280psi, any lower and the system needs head pressure controls or it will crash, you won't be able to maintain control of the low side and you might slug the compressor, variable speed equip might be the exception.
Do you know why on carrier heat pumps only why you have to get high side pressure in heating mode on the larger hot discharge line service port and if you check the 3/8 service port pressure it will be close to your suction pressure? On every other manufacturer you get high side pressure on the 3/8 service port in heating and cooling. Thanks!
Brian, That is because they have the metering device in the piston chamber right before your port when the subcooled liquid is flowing from the indoor coil toward the outdoor coil. The piston is right under the nut. If the port were 3 inches closer to the indoor coil, it would be high pressure subcooled liquid. You are reading low pressure liquid with 20 percent flash gas at that port because it is right after the metering device in heat mode. Other manufacturers place their piston chamber inside the outdoor unit so it is further downstream, thanks
AC Service Tech LLC that makes sense I just would think the hot discharge gas pressure would be too high because of the increased temp / pressure created from the compressor to be an accurate high side pressure
Are you talking about following a manufacturer charging procedure for a heat pump in heat mode because other than that, we can't really check a charge in heat mode due to not knowing how much refrigerant is in the accumulator. We are stuck with total weight procedure or reducing condensor airflow to raise high side sat temp in cooling mode but it would need to be 38 degrees or higher ambient temp for that method, thanks
Excellent video
Thanks Jeff!
What is the suction pressure of ac unit with a r 410a charge
Nice video, you're a good teacher. bought a new house, and trying to evaluate the ac system. Nordyne 3 1/2 ton 1600 sq. ft house. the best my low side ever gets is at 11AM Low:92 r22 ring: 52. but at 4 in the after noon the system wont shut off at 78 degrees in the house. So low on 22? compressor going bad? High on 22? I've cleaned both sets of coils, evaporator was really bad. Advice?
Hey David, I would need to know if you have a txv or fixed orifice such as a piston or capillary tubing as the metering device in order to answer the question. Then I would need high and low pressures, superheat, subcooling, outdoor temp and indoor wet bulb temp. We don't go by pressures only in order to check a charge, thanks
BEST VIDEO ON TH-cam !!THX!!
Thanks Raybo!
Something I can't seem to understand is if the temperature outside is cool like 70s your suction pressure can seem low like at a 30-32 degree saturation but be perfectly fine. Like If its 70 degrees in the house my low side sat temp is like 30.. how does this work? Your videos help me in my career. I'm out here in FL as well thanks
If it is below 32 degrees sat temp then it would be freezing so that wouldn't be good. That would mean either low airflow, low refrigerant charge, liquid line restriction or low temperature inside the building. The evaporators for air conditioning are designed to run at around 40 degrees. That could mean anywhere between 32 and 55 degrees depending on the indoor temp crossing the coil and the outdoor temp. It has to be low enough to get the humidity in the building to condense and drip into the pan and low enough to absorb heat efficiently. Keep watching the videos. Look up "acservicetech superheat playlist" to learn more and check out the ones with the evap coil in the thumbnail, thanks
@@acservicetechchannel right I know below 32 degrees it's freezing.. however if the indoor temp is cold I notice my sat temp is very low BUT there would be no issues at all. Just confuses me. Thank you
@@dapperdon7212 aka Teflon Don
Hey I have a system that is reading 250 on high and low side
Awesome video 👏🏽👏🏽
Thank you !!
You're jesus son my friend your video's are very helpful. I really appreciate it. God bless you!!
Praise the Lord!
Thank you for your video, guru. My AC is RUDD UACC-036JAS, R22 refrigerant system, it has refrigerant leakage, the Tech refilled R22 to Low Pressure at about 62 psi, High Pressure is 220 psi, is it ok for cooling? but I feel it is slow to make rooms cool. What is the best psi of Low Pressure for my AC? Thanks.
he would need to check it with superheat or subcooling but the refrigerant will eventually leak out again. He would need to find and fix the leak. You could also check for 18-21 degree temp decrease between the return air and supply air to verify it is working correctly, thanks
Acservicetech this is really but really a exelente video man...can you make some more videos like this one explaining the pressures and the simtoms or problems like you did on this one...we really need videos like this one well I need videos like this one.
Thanks Pedro, check out these for now and then let me know what exactly you would like to see, thanks!
th-cam.com/play/PLxnHR5_D2ojxZI3-xx03Bttxe3xCqUD87.html
Thank you for your videos. I have a question about the "expected pressure" on the high side, can we take the SEER rating, refrigerate type and the outside temperature and add a constant value to get the expected high side pressure?
So for a example a R22 on a 85 degree day for a SEER 13 would mean the pressure should reflect 85 + 20 = 105 F. Then covert 105F on a PT chart?
Kow the are . Diffwrnce in temperraure of of out and room air and u factor the heat leakge rhrufh wall . Cilling and floor per hour canbw calculated using the following equation .. Heat leakge =ufactor xtemperature difference =uxAxTD (u=factor -Btus =area -squre feet Td=tempreaature difference -°f.
great job i think i added to much 410a to my mini split the psig reads 150 should i evacuate some
You would need to use superheat and subcooling to know what to do, thanks!
Where to normally find the metering devices on typical residential systems? Thanks
In the same panel as evaporator coil or right outside the evap coil usually unless it is a fixed orifice or exv. Those are usually at the condenser. But they are all on the liquid line going to the evap coil
So I charge refrigerators all the fine but I’m gonna be charging my RV AC tomorrow and it’s R410a. I dnt believe I have a way of measuring the 22oz charge. Do I just charge it running till I get around 110 psig on the low side ?
We usually use a digital scale for systems like that but you could check the type of metering device such as if it has a piston and use the superheat method likely, thanks
You mentioned that things are different in an inverter type system. Can you explain that more? I am seeing about 75psig on the low side of a R410a mini-split during operation and trying to figure out if that is somehow normal or if there is actually a leak.
Mini split manufacturers don't give us superheat or subcooling guidelines but just the total weight procedure for inverter type units unfortunately however the low side sat temp should not be below 32 degrees, thanks
Good VDO easy to understand thanks
Thanks sidtrex1!
My low side pressure reads 200+. When I add 410a, it goes even higher. High side reads 285. No idea what’s going on. It’s like it’s not taking my refrigerant.
Great video(class)you put on for us
Thanks a lot Mardino, and also the paperbacks just became available today on the website, acservicetech.com thanks