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 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
I've been a long time in the field 20yrs-and honestly all the way back to school I can't recall anyone being so thorough in teaching proper methods. I've said it before and I'm saying it again, you are the best on TH-cam!
Thanks so much for doing the work that you do and for being very thorough in the explanation of all of it. I have worked in the HVACR for a couple of years and now I'm in school for getting my degree in it. This is my first semester and we are just about to start learning about brazing. Thank you for the information on the nitrogen flow.
Mister.... you are the best!!! I'm a general contractor trying to learn AC repairs in installation my hat's off to you, you should be teaching, you are a "Maestro"
You would want to avoid going that high on older coils. You can also read a more precise and quicker pressure test using a digital manifold as the incremental changes can be seen faster, thanks!
You cannot exceed the low side test pressure listed on the data plate, if you don’t have the high and low side isolated. The pins on the compressor cannot handle those pressures of 350-400.
I'm a little confused on the pressure test. Once you have all three gauges at 200 psi and holding, shouldn't you close off the nitrogen feeding into the gauge set. Otherwise if there is a small leak wouldn't the continuous addition of nitrogen hide it by compensating?
Linn tech State College grad... My instructor way of teaching..... "Go look at your book". smh No hand on training whatsoever. Thank goodness for this video!!!!!!!!
If you want to support the ACSERVICETECH Channel and receive more HVAC Content, Correspond, or Collaborate on your endeavors- check out www.Patreon.com/acservicetech All of the ACSERVICETECH Playlists- th-cam.com/channels/OZR-1IqsAer9wzlvFgb4mA.htmlplaylists?view_as=public Submit your email to the ACSERVICETECH email updates list at info@acservicetech.com
Very useful video, lots of information here. This is the only vid on TH-cam where I have seen this oil blowout procedure. When doing this, do you always inject the Nitrogen on the vacuum (low pressure) side and put the can on the high pressure side, or do you inject the Nitrogen into the highest side off the ground so that gravity helps push the oil out the lowest (to the ground) side? thanks!
It just blows the oil onto the inner walls of the tubing so that you can pull a vacuum through all the existing tubing. it doesn't matter which side you push the oil through. We do usually pressurize on the liquid side though and put a cup under the port on the other side. It will not catch much but may catch some drops of oil, thanks!
Great videos! Water in the system will also make the micron gauge jump back and forth, unfortunately I see this more than I should (new construction multi-family).
Absolutely, oh man, that's a shame. They must have not brazed the ends on right away during the pressure test. Yeah you run into a lot of scenarios that you shouldn't have too. Thanks Sloany83!
acservicetech Our installers either didnt tape the ends good on rough-in or had their linesets open to the elements, aka back of their truck with open ends. We have rooftop units and ive ran into 4 out of 60 units so far having water in the system, hopefully the next 61 are better.
I do thank you very much for your excellent instructions and great detailed explanations. You are always during your videos answering all the what, why, how and what not to do with great details and explanations. Having said that, I know you are very busy but if you would please answer a few questions about the mini split AC: 1. As you know the mini split AC of all brands and kind has no high side shredder valve and I do not know why, so is it good idea to install one out side the system near the low side shredder valve? 2. I have a mini split AC under full maintenance including a leak repair on the condenser, as you know the metering device is just at the end of the condenser going to the evaporator, in this case is it OK to feed nitrogen gas from the low side all the way to the condenser to test the condenser leak repair? will nitrogen pass through metering device? and if so will it affect the metering device and or the high side of the compressor? 3. After doing system and line set vacuuming, is their a need to add 2 ounces or may be less of a compressor oil? I can not find any sold information on this issue? Last but not least, thank you very much for teaching so many people not just in the U.S.A. but around the globe as well!!!
The three videos- Combination gas valves and thermocouples, Thermopiles, and Thermocouple videos are in this short playlist, thanks- th-cam.com/play/PLxnHR5_D2ojwefn5vubZ7A8MA89Z6AnMU.html
I have a rear overhead air conditioner in my van it says that the coil is charged with nitrogen I’ve got hot pipes coming from the engine to make it they seem to be hot but I’m not sure how the air conditioning system works is that just circulating cold water from the coil in the front of the vehicle or is it Actually refrigerant ,best regards
It’s good practice never to install the micron gauge on any line that is flowing during the vacuum. It should be installed as far away as possible from the vacuum pump, on a connection facing upward. Use a small pigtail if necessary. Never install the micron gauge on the hoses, or on the vacuum pump itself.
Hi thank you for the great useful video. I have encountered a problem regarding the pressure drop of compressor at low circuit of my chiller unit. The scenario is described as below: My chiller has 3 unit of scroll compressor, when the first compressor is running, the the low circuit pressure shown 4.5 bar and when second compressor cut-in, the low circuit pressure starts to drop to 3.5 and when the last compressor cut-in, the pressure drop again to 2.5 and the system will alarmed. Then the system will automatically cut-off both second and third compressor and the low circuit pressure will again increase to 4.5 bar again. After few minutes, this happened again and again. I have struggling to think of the causes of this problem. Is it because of there is a leakage of my circuit or the expansion valve has malfunction? Or do you have any idea about this? Thank you so much in advance.
Great explanation, I have a question though, on split systems where the condenser is located on a roof and indoor unit on suspended ceiling I have noticed oil traps. When servicing evaporator coil would it be wise to cut coil and remove to do a coil wash or do a oil blow out in a reverse direction to avoid plugging up metering device? Thanks for sharing!
Thanks for your nitrogen pressure test. One question I have is how do you know you don’t have a leak when you left the system pressured by the nitrogen tank? Shouldn’t you isolate the system from the nitrogen tank to do this?
Could you provide a link to where one can get the short, yellow 1/4" female to 1/4" female hose? Googled but nothing found except ones with male 1/4" and a ball valve. Thanks. Excellent procedure steps and like the vacuum setup for a quicker vacuum setup then the procedure I use. As know, the closer the vac gauge is located on the system e.g. as directly connected to the Vapor line port to eliminate hoses, the more accurate level of vacuum obtained. So with my 4-valve manifold gauge set, I have used two vacuum-rated core removal tools (CRTs Appion brand) on both the liquid and vapor line with Schrader valves removed. Vacuum more quickly obtained w/ the micron level shown right at the system. A key step though is, before opening the CRT ball valve to re-insert Schrader valves, one need to slightly pressurize the system with
Beautiful thing, good job! The hose you saw was off of the Hilmor set and was from the manifold hose after the yellow hose valve. I am having a hard time finding that too however this is a short 1/4" by 1/4" female coupler from Supco - amzn.to/2kFrbU9
I try to get a little length away from the vacuum when possible. You may get a little oil in the gauge if it is connected in series and the hoses have not been blown out lately with nitrogen but no the micron gauge semms to last. I will have to pull out my 14 year old one some time and run a vac on that. This manufacturer states you can clean the sensor with rubbing alcohol and I have but not that often, Thanks a lot Ron!
Nitrogen is affected as well but not with the movement that refrigerant has. Refrigerant has liquid to draw more vapor from for pressurization. Nitrogen will certainly move as well. When I pressure test water lines, code is 80psi so I put 85 psi of air in knowing it will drop or rise depending on temp. There obviously is a lack of water vapor in nitrogen. The nitrogen will still expand if you put it in on a cold day or reduce in pressure if you put it in on a hot day or from a warm vehicle into a cold line or a line surrounded by cold air. If you are putting 200psi in, we are just talking probably 5-10 psi over a couple hours. It is just another thing to mess your mind up if one was not aware after a half an hour the pressure fell 2 psi. You might think you have a leak. Thanks Capitol, you made me question myself for a second there, ha ha. I had to check myself before answering.
It can be 15 minutes or a day but I usually bubble leak check my joints too. The vacuum test will also verify that there are no leaks as well, thanks. here is a video on vacuuming- th-cam.com/video/jlzecsOImqs/w-d-xo.html
I am struggling with choosing a good digital micron guage. I am looking at the 2 I see you use which are ofcourse the CPS VG200 and the SUPCO VG64. I have looked at almost 100 reviews on both between Amazon, EBay, Google Search and HVAC forums and honestly 80-90% of the reviews say do not buy and stay away from them. Reasons are bad leaks, unit power shutting off and false readings. I see you using them with no issues. Can you recommend other ones or maybe explain why these do or do not have these issues? Just not wanting to waste money and at the same time not have to spend $300-$400. I was just getting ready to purchase the CPS today from your tool list on Amazon but it says it won't be here for 1-2 months and I can't wait that long. Really appreciate your opinion.
Hey James, sorry to hear that vacuum gauge is no longer an in stock item. Crazy. I looked around on amazon. Maybe try to purchase the cps one through another distributor. I have had good success so far and to date I have not had a single person come back and say they didn't like it. Thats not to say that won't happen or that there wont be a lemon out there but I am really happy with that version.
great video am going to be replacing txv on trane air handler first thing i want to ask if u can give suggestion is that its no room to replace txv inside the A coil whats the best way to replace the txv removing the coil ?and would it have oil in the line should i use same procudure as yours would help to know,thanks
Yes we would remove the coil if there is not enough room and if we had to unbraze and braze the external equalization port. make sure to replace the filter drier afterward as well. Yes you would do an oil blowout before vacuuming. You don't need too much pressure for this, thanks
I appreciate your videos. One question about pressure testing old systems. Is it safe to pressure test the condensing unit (condensing coil) at the same time while testing the rest of the system?
I don't get it, how is some oil in a line somewhere in the system going to change anything as far as "running" a vacuum? Any air (moisture laden or otherwise) that is on the other side of it will be pressurized through the oil...heck I've used a vacuum pump to pump air out of very thick fluids like urethane paint, and it works great...what am I missing here?
I am describing when you use a two hose setup because you are pulling a vacuum from both sides. WE usually don't do a single hose vacuum because of how slow it is because of the metering device restriction half way down the tubing. I did another video that you may want to check out. 5 reasons why a micron gauge reading may jump around- th-cam.com/video/Ks3MtPmXDUE/w-d-xo.html
@@acservicetechchannel Ah, I see now, that makes sense...thanks for taking the time to answer, I will check out your other vid. This one was very informative. ;-)
Had to watch about six times around the 3:45 mark - a subtle skip in the video and no instruction or clear visual regarding closing off the nitrogen and isolating the system. And yet after that he points to the secondary gauge at the nitrogen tank noting that it's "allowing" the pressure on the manifold gauges, as if in present tense?
A little off-topic, but do you know which fitting I would need to go from my argon/co2 guage to the 1/2" acme fitting of an automotive a/c manifold hose?
Yes that is correct! I was thinking of pulling out my old 14 year old micron gauge and doing a video with it. It's the same version but a little worse for wear. They work going through with two ports or with the one port and a cap on, thanks!
Hi there I would like to ask you a question about r134a I fixed a friage few days ago and it takes 4.25 oz of freone I did not weigh up the freon just going by the gages how much it should read on the gages Thank you
I use this Nitrogen Regulator - amzn.to/2bXdR5f -- and the nitrogen tank is a 60 cu ft. I usually have links to the tools used in the video in the description section below the video. Thanks attisso togbo!
There is no liquid so you could technically use it on it's side. I will tell you, that I usually use it vertically and I always store and transport vertically. I was just trying to get it in the shot so you could see it. Thanks
We use dry nitrogen for pressure testing and oil blowouts only. We need to vacuum all the nitrogen out before adding he refrigerant in, otherwise, the nitrogen will get pumped through the system not allowing the saturated refrigerant state to be very large in the coils and will drive up the discharge pressure, thanks
You would need to disconnect the liquid flare at the outdoor unit. if you do the oil blowout from the vapor side, you will accidentaly blow the oil out of the tube since the liquid line is so small. If possible, try blowing from the liquid flare and allow the nitroge out of the vapor port. the object is to blow the oil onto the inner walls of the tubing but not out of the system, thanks!
Hi All, I have a new outside evap coil, when I do the vacuum test do I open a service valves ? Nitrogen test with service valves closed being done and I have no leaks. The new unit have nitrogen inside, how do I precise in this case ? Thank you
@@acservicetechchannel I would never lay it down. I’ve seen water at the bottom of some tanks. Unless it’s certified dry nitrogen, it may have not been handled properly.
9:14 ughh....maybe it's because I'm so tired/depressed/out of it, or whatever, but I'm just not following this and don't have the mental energy to make sense of it. If you think I'm an idiot, I envy you for never having been in this frame of mind.
No one is an idiot for having a question ever! I am teaching and questions are good for the individual that is processing and engaging. That was just a little pressure locked at the valve. The same thing happens on the ball valves of valve core removal tools. I always try to not allow positive pressure into the vacuum gauge whether nitrogen or refrigerant. I don't want any oil to get onto the sensor in the vacuum gauge that would mean I then need to try to clean the sensor. I also don't add pressure into the vacuum gauge because I don't want any leaks, thanks John and no worries I am there in that state too at times!
one correction, the volume of Nitrogen will not change due to temperature, thus it it called "inert". Thats why I always try to pull the residual refrigerant out of the oil sump in the compressor so that it won't influence the reading of the inert dry nitrogen during a pressure test.
I am sorry but nitrogen is inert which is chemically unresponsive. It is a gas and will increase in pressure if temp surrounding it rises. This won't be as severe as a refrigerant but it will rise or fall a little depending on temp. I even show my students on small projects without refrigerant or air in the lines but only nitrogen. Once again, not much but it will rise or fall a very small amount, Thanks
@@acservicetechchannel I'm not trying to contradict, that's what i was told since i started doing ac work since 1989 and don't take me wrong, I've learned so much from your videos. Keep up the good work. 👍
Great video....but..but why is it that no one shows proper connection of hoses! It would be soooo helpful to add 5 seconds of video to show which hose goes where! It’s great without it...but without proper connection it’s not very helpful...remember you are doing it for people who are not sure what they are doing!
Hey Vlad, look up "acservicetech connect check charge disconnect procedure" and you will see them. Honestly, it just has to do with time and trying to get the shot set up so I know it works and can fit the frame as close as I can while not having to block the camera when doing it. thanks
You may want to consider cutting the pipe out and swaging it back in to avoid that. That also reduces the amount of time that you would be present when phosgene could occur if you are having to braze in an area where you know to be oil located there. People hold their breath, bring in fresh air or wear scba setup. SCBA i=would be the safest and best alternative. In reference to the metering device, it would not clog it up but you could try doing the oil blow out in the other direction. The problem being that you may not have enough force to sling it up. If you were to replace the outdoor unit then yes I would look at emptying that trap by cutting in that area. You would want to braze the new filter drier near the indoor coil anyway to keep it from being outside. Great questions, thanks youngbeechnut78!
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 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.com
acservicetech thank you so much, you explain very well
@@mohsengholami5550 I don’t think he explained very well. Now I have more questions than before.
I've been a long time in the field 20yrs-and honestly all the way back to school I can't recall anyone being so thorough in teaching proper methods. I've said it before and I'm saying it again, you are the best on TH-cam!
Thank you very much Marcus, I appreciate it!
I had a pretty bad teacher in hvac school, I thank the lord Jesus I found your videos!
Praise the Lord! Thanks Lee!
Best HVAC learning channel on the internet. Hands down. Thank you so much for all of this free info. Gold mine.
About time someone explained this procedure properly.
Thanks Transport!
Wow, your production values have come way up over the years.
Thanks so much for doing the work that you do and for being very thorough in the explanation of all of it. I have worked in the HVACR for a couple of years and now I'm in school for getting my degree in it. This is my first semester and we are just about to start learning about brazing. Thank you for the information on the nitrogen flow.
Thanks Brandon, look up "acservicetech brazing with nitrogen" for more videos, thanks
Mister.... you are the best!!! I'm a general contractor trying to learn AC repairs in installation my hat's off to you, you should be teaching, you are a "Maestro"
Thanks Al, I taught high school and night adult HVACR classes. I appreciate the comment!
I’ve always heard 350-400 psi is good. I’m glad you covered this!
You would want to avoid going that high on older coils. You can also read a more precise and quicker pressure test using a digital manifold as the incremental changes can be seen faster, thanks!
You cannot exceed the low side test pressure listed on the data plate, if you don’t have the high and low side isolated. The pins on the compressor cannot handle those pressures of 350-400.
good video, you showed detail of what you are doing.
Thanks Rami Hawari!
Great video acservicetech. Really enjoyed it! Look fwd to the next one...Cheers
Thanks Paul HVAC!
I have great tips from all the videos that you have. Thanks for taking the time to teach us all.
I see that Todd, thanks and glad you like them!
Thanks Craig for the tips❤
Any time!
Thanks! You explained this issue perfectly.
I'm a little confused on the pressure test. Once you have all three gauges at 200 psi and holding, shouldn't you close off the nitrogen feeding into the gauge set. Otherwise if there is a small leak wouldn't the continuous addition of nitrogen hide it by compensating?
He forgot that, I think
Linn tech State College grad... My instructor way of teaching..... "Go look at your book". smh No hand on training whatsoever. Thank goodness for this video!!!!!!!!
Very sad, I am sorry to hear! Thank you very much for letting me know!
Best videos in youtube hands down.
Thanks imjustme1991!
The last HVAC company I worked for did not do Nitrogen Pressure testing and had apprentices with no EPA 608 certification handling refrigerants.
And that's why you aren't there any more. Their Loss! That is not good, thanks Game Wizard!
If you want to support the ACSERVICETECH Channel and receive more HVAC Content, Correspond, or Collaborate on your endeavors- check out www.Patreon.com/acservicetech
All of the ACSERVICETECH Playlists- th-cam.com/channels/OZR-1IqsAer9wzlvFgb4mA.htmlplaylists?view_as=public
Submit your email to the ACSERVICETECH email updates list at info@acservicetech.com
Very useful video, lots of information here. This is the only vid on TH-cam where I have seen this oil blowout procedure. When doing this, do you always inject the Nitrogen on the vacuum (low pressure) side and put the can on the high pressure side, or do you inject the Nitrogen into the highest side off the ground so that gravity helps push the oil out the lowest (to the ground) side? thanks!
It just blows the oil onto the inner walls of the tubing so that you can pull a vacuum through all the existing tubing. it doesn't matter which side you push the oil through. We do usually pressurize on the liquid side though and put a cup under the port on the other side. It will not catch much but may catch some drops of oil, thanks!
Well explained and in-depth!
Thanks PanzerFaust!
Great videos! Water in the system will also make the micron gauge jump back and forth, unfortunately I see this more than I should (new construction multi-family).
Absolutely, oh man, that's a shame. They must have not brazed the ends on right away during the pressure test. Yeah you run into a lot of scenarios that you shouldn't have too. Thanks Sloany83!
acservicetech Our installers either didnt tape the ends good on rough-in or had their linesets open to the elements, aka back of their truck with open ends. We have rooftop units and ive ran into 4 out of 60 units so far having water in the system, hopefully the next 61 are better.
My question is did you isolate the compressor went you pressurized the system?
Very good 👍
Thanks Jorge Mejia!
I do thank you very much for your excellent instructions and great detailed explanations. You are always during your videos answering all the what, why, how and what not to do with great details and explanations. Having said that, I know you are very busy but if you would please answer a few questions about the mini split AC:
1. As you know the mini split AC of all brands and kind has no high side shredder valve and I do not know why, so is it good idea to install one out side the system near the low side shredder valve?
2. I have a mini split AC under full maintenance including a leak repair on the condenser, as you know the metering device is just at the end of the condenser going to the evaporator, in this case is it OK to feed nitrogen gas from the low side all the way to the condenser to test the condenser leak repair? will nitrogen pass through metering device? and if so will it affect the metering device and or the high side of the compressor?
3. After doing system and line set vacuuming, is their a need to add 2 ounces or may be less of a compressor oil? I can not find any sold information on this issue?
Last but not least, thank you very much for teaching so many people not just in the U.S.A. but around the globe as well!!!
great work
thanks mm F!
ty u 4 the great video i always learn something from you
Thanks David!
Excellent video thank you for sharing!!!
Thanks Jimbola77!
How does nitrogen go through the compressor? And if it does!! Is it possible to blow oil out of the compressor as well?
When you pressurized the system do you front sitting the king valve, or you back sitting the king valve
Great video! Can you do a video on Thermocouples & Thermopiles?
The three videos- Combination gas valves and thermocouples, Thermopiles, and Thermocouple videos are in this short playlist, thanks- th-cam.com/play/PLxnHR5_D2ojwefn5vubZ7A8MA89Z6AnMU.html
We use r11 flush to clean out oils and other contaminants on existing line sets
That works well, thanks Joe!
I have a rear overhead air conditioner in my van it says that the coil is charged with nitrogen I’ve got hot pipes coming from the engine to make it they seem to be hot but I’m not sure how the air conditioning system works is that just circulating cold water from the coil in the front of the vehicle or is it Actually refrigerant ,best regards
Sorry， didn't get why is there oil in the unit, especially in the new one. I was surprised to get it on my fingers.
It’s good practice never to install the micron gauge on any line that is flowing during the vacuum. It should be installed as far away as possible from the vacuum pump, on a connection facing upward. Use a small pigtail if necessary. Never install the micron gauge on the hoses, or on the vacuum pump itself.
Hi thank you for the great useful video.
I have encountered a problem regarding the pressure drop of compressor at low circuit of my chiller unit.
The scenario is described as below:
My chiller has 3 unit of scroll compressor, when the first compressor is running, the the low circuit pressure shown 4.5 bar and when second compressor cut-in, the low circuit pressure starts to drop to 3.5 and when the last compressor cut-in, the pressure drop again to 2.5 and the system will alarmed. Then the system will automatically cut-off both second and third compressor and the low circuit pressure will again increase to 4.5 bar again. After few minutes, this happened again and again.
I have struggling to think of the causes of this problem. Is it because of there is a leakage of my circuit or the expansion valve has malfunction?
Or do you have any idea about this?
Thank you so much in advance.
During the oil blowout procedure on an empty system, do I have the service valves to condenser open or closed?
Great explanation, I have a question though, on split systems where the condenser is located on a roof and indoor unit on suspended ceiling I have noticed oil traps. When servicing evaporator coil would it be wise to cut coil and remove to do a coil wash or do a oil blow out in a reverse direction to avoid plugging up metering device? Thanks for sharing!
Thanks for your nitrogen pressure test. One question I have is how do you know you don’t have a leak when you left the system pressured by the nitrogen tank? Shouldn’t you isolate the system from the nitrogen tank to do this?
I closed off the manifold gauge set handles and you would watch the manifold set gauges. Digital ones are even better for pressure testing, thanks
How much nitrogen pressure is good for leak testing in indoor and outdoor unit
Really good info man!!!
Thanks Pedro Rodriguez!
great video thank you. On the oil blow out, have you ever had to put oil back in a split system?
No, not much comes out at all. The secret is to blow it onto the walls of the tubing inside before the vacuum.
Could you provide a link to where one can get the short, yellow 1/4" female to 1/4" female hose? Googled but nothing found except ones with male 1/4" and a ball valve. Thanks. Excellent procedure steps and like the vacuum setup for a quicker vacuum setup then the procedure I use. As know, the closer the vac gauge is located on the system e.g. as directly connected to the Vapor line port to eliminate hoses, the more accurate level of vacuum obtained. So with my 4-valve manifold gauge set, I have used two vacuum-rated core removal tools (CRTs Appion brand) on both the liquid and vapor line with Schrader valves removed. Vacuum more quickly obtained w/ the micron level shown right at the system. A key step though is, before opening the CRT ball valve to re-insert Schrader valves, one need to slightly pressurize the system with
Beautiful thing, good job! The hose you saw was off of the Hilmor set and was from the manifold hose after the yellow hose valve. I am having a hard time finding that too however this is a short 1/4" by 1/4" female coupler from Supco - amzn.to/2kFrbU9
I have HVAC system with Condensing Pressure Regulator Types KVR and NRD. How can i make vaccum to this system?
buy connecting vacuum guage to manifold do you worry about compressor oil affecting vacuum guage accuracy? Nice video thank you.
I try to get a little length away from the vacuum when possible. You may get a little oil in the gauge if it is connected in series and the hoses have not been blown out lately with nitrogen but no the micron gauge semms to last. I will have to pull out my 14 year old one some time and run a vac on that. This manufacturer states you can clean the sensor with rubbing alcohol and I have but not that often, Thanks a lot Ron!
thanks for posting,I thought that nitrogen pressure is not affected by temperature?
Nitrogen is affected as well but not with the movement that refrigerant has. Refrigerant has liquid to draw more vapor from for pressurization. Nitrogen will certainly move as well. When I pressure test water lines, code is 80psi so I put 85 psi of air in knowing it will drop or rise depending on temp. There obviously is a lack of water vapor in nitrogen. The nitrogen will still expand if you put it in on a cold day or reduce in pressure if you put it in on a hot day or from a warm vehicle into a cold line or a line surrounded by cold air. If you are putting 200psi in, we are just talking probably 5-10 psi over a couple hours. It is just another thing to mess your mind up if one was not aware after a half an hour the pressure fell 2 psi. You might think you have a leak. Thanks Capitol, you made me question myself for a second there, ha ha. I had to check myself before answering.
real good video
Thanks trukin forever!
always great, thanks ...
Thanks Pei Broker!
I'm about to get this done tomorrow. How long should the nitrogen be in there to detect a leak?
It can be 15 minutes or a day but I usually bubble leak check my joints too. The vacuum test will also verify that there are no leaks as well, thanks. here is a video on vacuuming- th-cam.com/video/jlzecsOImqs/w-d-xo.html
Well Done, Thank You
Thanks Allen!
Thanks Allan Kenney!
I am struggling with choosing a good digital micron guage. I am looking at the 2 I see you use which are ofcourse the CPS VG200 and the SUPCO VG64. I have looked at almost 100 reviews on both between Amazon, EBay, Google Search and HVAC forums and honestly 80-90% of the reviews say do not buy and stay away from them. Reasons are bad leaks, unit power shutting off and false readings. I see you using them with no issues. Can you recommend other ones or maybe explain why these do or do not have these issues? Just not wanting to waste money and at the same time not have to spend $300-$400. I was just getting ready to purchase the CPS today from your tool list on Amazon but it says it won't be here for 1-2 months and I can't wait that long.
Really appreciate your opinion.
Hey James, sorry to hear that vacuum gauge is no longer an in stock item. Crazy. I looked around on amazon. Maybe try to purchase the cps one through another distributor. I have had good success so far and to date I have not had a single person come back and say they didn't like it. Thats not to say that won't happen or that there wont be a lemon out there but I am really happy with that version.
Before you do that... Do you need to recovee the refrigerant?
did i figure this out?
Hi, thank you what happens if you close the nitrogen tank right away after you put the pressure into the system can you do that?
You could do that but you should also have a way of locking the nitrogen in the system for a test while disconnecting the nitrogen tank, thanks!
great video am going to be replacing txv on trane air handler first thing i want to ask if u can give suggestion is that its no room to replace txv inside the A coil whats the best way to replace the txv removing the coil ?and would it have oil in the line should i use same procudure as yours would help to know,thanks
Yes we would remove the coil if there is not enough room and if we had to unbraze and braze the external equalization port. make sure to replace the filter drier afterward as well. Yes you would do an oil blowout before vacuuming. You don't need too much pressure for this, thanks
acservicetech thank you
What pressure do you prefer to test mini splits?
You would test under the max design pressure found on the rating plate, thanks!
I appreciate your videos. One question about pressure testing old systems. Is it safe to pressure test the condensing unit (condensing coil) at the same time while testing the rest of the system?
Reading your question 3 years after. Did you get any answers! I’m curious about your question as well. I know that has to do with service ports.
I don't get it, how is some oil in a line somewhere in the system going to change anything as far as "running" a vacuum? Any air (moisture laden or otherwise) that is on the other side of it will be pressurized through the oil...heck I've used a vacuum pump to pump air out of very thick fluids like urethane paint, and it works great...what am I missing here?
I am describing when you use a two hose setup because you are pulling a vacuum from both sides. WE usually don't do a single hose vacuum because of how slow it is because of the metering device restriction half way down the tubing. I did another video that you may want to check out. 5 reasons why a micron gauge reading may jump around- th-cam.com/video/Ks3MtPmXDUE/w-d-xo.html
@@acservicetechchannel Ah, I see now, that makes sense...thanks for taking the time to answer, I will check out your other vid. This one was very informative. ;-)
Question. Is the valve on the liquid line mid seated?
On this system, the service valve is a two position valve, not a 3 position valve, thanks
Had to watch about six times around the 3:45 mark - a subtle skip in the video and no instruction or clear visual regarding closing off the nitrogen and isolating the system. And yet after that he points to the secondary gauge at the nitrogen tank noting that it's "allowing" the pressure on the manifold gauges, as if in present tense?
A little off-topic, but do you know which fitting I would need to go from my argon/co2 guage to the 1/2" acme fitting of an automotive a/c manifold hose?
Sorry I am not sure Anthony
great info, I purchased the hilmor gauges myself and love them! do you just have a cap on the other connection of the micron gauge?
Yes that is correct! I was thinking of pulling out my old 14 year old micron gauge and doing a video with it. It's the same version but a little worse for wear. They work going through with two ports or with the one port and a cap on, thanks!
acservicetech awesome thank you so much! can you do a oil blow out with the king valves open? or will it blow all the compressor oil out?
Hi there I would like to ask you a question about r134a I fixed a friage few days ago and it takes 4.25 oz of freone I did not weigh up the freon just going by the gages how much it should read on the gages
Thank you
It has to be weighed in on a refrigerator with no sight glass that is that small, thanks
Hi, what kind of nitrogen tank and regulator is good to use on heat pumps?
I use this Nitrogen Regulator - amzn.to/2bXdR5f -- and the nitrogen tank is a 60 cu ft. I usually have links to the tools used in the video in the description section below the video. Thanks attisso togbo!
I was thinking the nitrogen bottle had to be set up right?
There is no liquid so you could technically use it on it's side. I will tell you, that I usually use it vertically and I always store and transport vertically. I was just trying to get it in the shot so you could see it. Thanks
what's different and the same between R22 and nitrogen ?
We use dry nitrogen for pressure testing and oil blowouts only. We need to vacuum all the nitrogen out before adding he refrigerant in, otherwise, the nitrogen will get pumped through the system not allowing the saturated refrigerant state to be very large in the coils and will drive up the discharge pressure, thanks
How do I do an oil blow out on a mini split system. My micron gage is jumping and I can’t draw a good vacuum
You would need to disconnect the liquid flare at the outdoor unit. if you do the oil blowout from the vapor side, you will accidentaly blow the oil out of the tube since the liquid line is so small. If possible, try blowing from the liquid flare and allow the nitroge out of the vapor port. the object is to blow the oil onto the inner walls of the tubing but not out of the system, thanks!
Hi All, I have a new outside evap coil, when I do the vacuum test do I open a service valves ? Nitrogen test with service valves closed being done and I have no leaks. The new unit have nitrogen inside, how do I precise in this case ? Thank you
Look up "acservicetech vacuum playlist" thanks
When doing pressure/vaccum test after swapping a compressor, would it affect the compressor oil while its under vaccum?
No it won't suck out the oil or blow it out. The compressor does not allow pressure to cross while it is off, thanks Sergio!
No, thank you professor!
Let's "go ahead" and do a nitrogen test on this A/C unit.
during the pressure test if the outside or inside temperature increased or changed would the temperature change the pressure on the system?
Yes absolutely, the pressure would change depending on the temp.
acservicetech thank you for your replies and thank you for making videos
No problem THE GENIUS!
Can co2 be use to pressure test and soft soldering?
It could be used. It is just not what distributors usually stock but some techs use that.
acservicetech thanks that helps me a lot.
Must the nitrogen cylinder lie or stand? Perhaps over head?
The Nitrogen is just gas so it doesn't matter but I usually keep it standing upright. I just moved it the get it in the shot, thanks
@@acservicetechchannel I would never lay it down. I’ve seen water at the bottom of some tanks. Unless it’s certified dry nitrogen, it may have not been handled properly.
التعامل مع الغاز خطير جدا
9:14 ughh....maybe it's because I'm so tired/depressed/out of it, or whatever, but I'm just not following this and don't have the mental energy to make sense of it. If you think I'm an idiot, I envy you for never having been in this frame of mind.
No one is an idiot for having a question ever! I am teaching and questions are good for the individual that is processing and engaging. That was just a little pressure locked at the valve. The same thing happens on the ball valves of valve core removal tools. I always try to not allow positive pressure into the vacuum gauge whether nitrogen or refrigerant. I don't want any oil to get onto the sensor in the vacuum gauge that would mean I then need to try to clean the sensor. I also don't add pressure into the vacuum gauge because I don't want any leaks, thanks John and no worries I am there in that state too at times!
one correction, the volume of Nitrogen will not change due to temperature, thus it it called "inert". Thats why I always try to pull the residual refrigerant out of the oil sump in the compressor so that it won't influence the reading of the inert dry nitrogen during a pressure test.
I am sorry but nitrogen is inert which is chemically unresponsive. It is a gas and will increase in pressure if temp surrounding it rises. This won't be as severe as a refrigerant but it will rise or fall a little depending on temp. I even show my students on small projects without refrigerant or air in the lines but only nitrogen. Once again, not much but it will rise or fall a very small amount, Thanks
all gases change volume due to temperature or external pressure changes. That's not the meaning of inert.
now now guys, the volume won't change if its in a fixed volume system will it? :P
I thought nitrogen would not react to any temperature
It does but not as much as air but certainly does change pressure due to temp, thanks
@@acservicetechchannel I'm not trying to contradict, that's what i was told since i started doing ac work since 1989 and don't take me wrong, I've learned so much from your videos. Keep up the good work. 👍
Great video....but..but why is it that no one shows proper connection of hoses! It would be soooo helpful to add 5 seconds of video to show which hose goes where! It’s great without it...but without proper connection it’s not very helpful...remember you are doing it for people who are not sure what they are doing!
Hey Vlad, look up "acservicetech connect check charge disconnect procedure" and you will see them. Honestly, it just has to do with time and trying to get the shot set up so I know it works and can fit the frame as close as I can while not having to block the camera when doing it. thanks
The question was in regards to preventing oil from catching on fire while trying to un braze the joints.
You may want to consider cutting the pipe out and swaging it back in to avoid that. That also reduces the amount of time that you would be present when phosgene could occur if you are having to braze in an area where you know to be oil located there. People hold their breath, bring in fresh air or wear scba setup. SCBA i=would be the safest and best alternative.
In reference to the metering device, it would not clog it up but you could try doing the oil blow out in the other direction. The problem being that you may not have enough force to sling it up. If you were to replace the outdoor unit then yes I would look at emptying that trap by cutting in that area. You would want to braze the new filter drier near the indoor coil anyway to keep it from being outside. Great questions, thanks youngbeechnut78!