How To Recharge an Auto AC System

In this video I show you how to properly recharge an empty automotive R134a A/C system after servicing it.
I can not stress safety enough when working with refrigerant gloves and safety glasses are a must.
Equipment wise the bare minimum you will need is a manifold gauge set, a motorized vacuum pump, disposable refrigerant cans, and a tapping valve.
If your system has ANY refrigerant in it as indicated by your gauge set you MUST have it evacuated before disassembling the system. Venting refrigerant from the system to the atmosphere is against EPA regulations.
"Welcome To The Show" Kevin MacLeod (incompetech.com)
Licensed under Creative Commons: By Attribution 3.0 License
creativecommons.org/licenses/b...
Due to factors beyond the control of Bushougoma, it cannot guarantee against unauthorized modifications of this information, or improper use of this information. Bushougoma assumes no liability for property damage or injury incurred as a result of any of the information contained in this video. Bushougoma recommends safe practices when working with the tools or equipment seen or implied in this video. No information contained in this video shall create any express or implied warranty or guarantee of any particular result. Any injury, damage or loss that may result from improper use of these tools, equipment, or the information contained in this video is the sole responsibility of the user and not Bushougoma.

[@Bushougoma]

NOTE: I left out purging the extra refrigerant from the high side hose this was INTENTIONAL. As doing it improperly which is VERY easy if you don't follow the procedure exactly will put FULL HIGH SIDE PRESSURE on your charge can or cylinder which can cause cause the one time relief valve to blow venting all of the refrigerant from the can and your system potentially on you. Refrigerant cans have a slice partially punched out on the bottom of the can and cylinders have a thin metal disc near the top of the cylinder. When their maximum pressure is exceeded they will vent all of the refrigerant they contain. This escaping refrigerant can flash freeze skin and cause serious injury.

[@screenflot]

Just thought I would thank you for the great video. I replaced the condenser and accumulator in my 2003 Grand Cherokee and so started with an empty system. I purchased an Extreme Power vacuum pump and manifold set on Amazon for 160 bucks and three cans of r134. After a successful vacuum and leak test, the only problem was the compressor not coming on due to low pressure. Some forum searching led me to pulling the AC relay at the fusebox and jumping the 1 and 2 terminals(the two large ones) and the compressor came on. My digital kitchen scale didnt work so well, so at 27 ounce capacity for my system I put in a little over two 12 ounce cans. Now I have super cold AC and a sense of accomplishment. Thanx again!

[@jojo123469]

Finally, this fellow youtuber, explains the importance of vacuuming out the ac system and why it should be done. What a great thorough video on AC system charging and testing.. Thanks so much...Canada..

[@ramohino]

Yes, one thing make sure you do NOT turn the manual quick connect ALL THE WAY DOWN. Watch the gauges as you manually turn them one a a time until they engage the schrader valve, you will notice a small movement on the gauge and then you know the schrader valve is open. I had to replace one of my schrader valve due to turning manual quick connect ALL THE WAY DOWN. GREAT VIDEO!!!

[@bwagenberg]

The most accurate video on the subject. Addresses everything missed more recently by ChrisFix. Thank you very much. Please do a follow up about how to add PAG oil and indicator dye.

[@rtj49]

The best video I have seen on KZbin on use of the ac manifold set for autos. You put the others to shame. Thanks

[@garydrury6698]

This is the most complete, accurate, and professional video I have seen on the subject. Well done, and thanks for sharing!

[@E39M5SPEED]

Gary Drury I agree this guy is very accurate

[@troyb6036]

E39M5SPEED I don't agree fully because many things were said for someone who is advance . After he started to use the scale the explanation was fast and not easy to understand

[@yagousera]

@@troyb6036 - His explanation when started to explain the "Weight, Measurement and Distribution" of the tank to scale was excellent and could not have done a better job of explaining it. I've never done an AC job but have mechanic and crafted many things to know that explanation of the tank. Maybe you need to take a course on "Weight, Measurement and Distribution" that will allow you to grasp things as the purpose of scales quickly.

[@yagousera]

@Bruce Lee - I think you need to first decipher someone's answer if your going to put it under the mill. He did explain the theory "Right" so maybe you need to do your research because when the system asks for so many pounds that's what you put in. Nothing else was talked about nut that so get your research together cause it seems to flake somewhere else. If you have a problem, Hey showing is everything where talk is "BS".

[@olayeyesundaychris8649]

Can will see this products

[@MichaelBorne-rh8co]

Excellent vid. Way better than ALL the rest of them on this entire youtube website!

[@spelunkerd]

That's a very good summary. I hope you extend this series to review other issues, like estimating how much oil to add, flushing the system, and finding leaks.

[@muffinsbear]

Yes, you forgot to mention the lubricating oil necessary for the compressor.

[@bobchannell1775]

This is, without a doubt, one of the most professionally done a/c videos. A lot of videos on a/c leave a lot to be desired, but this one explains it in very easy to understand, and quite professional terms. What a great job!

[@jimdandy6472]

Thanks for making this very detailed video! It really helped seeing the steps in a real world application.

[@patrickmcmurray9446]

Hey Bushougoma; your video is excellent. Your comments are also very informative. You show great patience with many comments, and explain things in detail. Nice going...

[@tempest411]

Very good video. Very few people understand the importance of pumping down the system though, so it's good you effectively communicated that.

[@elijah2078]

I go to this video as a refresher each time I prepare to do auto a/c work. Very instructional!!! Thank You Sir!!!!!

[@KyrosNox]

You my friend would make a very good teacher. Keep up the excellent work.

[@greenthum39]

thank you for taking the time to make this video it's help me fix my a.c. in my suv you did a great job showings how everything works and what not to do. I hope you keep making them

[@gbmmben]

Great job of explaining. I really appreciate how thorough you are

[@garnetsuss4881]

Great video! I've easily spent 80hrs reading and watching videos to learn as much as I can. This is the best tutorial I've come across. Thank you!

[@overmanonfire]

by far the best video i found on youtube showing how to get the job done, Thanks a lot

[@issamadam9352]

Yes is the best video ever on you tube.very informative.

[@dekebell3307]

EXACTLY what I was looking for! Thanks so much!

[@tombstonesmith3005]

Very detailed tutorial on automotive A/C vacuum /charging .Thank you

[@abedj1220]

thanks for the details. I am ready to charge my system after I hit a deer and had to replace the condenser and while I had the system open I replaced the accumulator and added a little pag150 oil I bought a harbor freight pump and evacuated it last fall. Now weather is getting warmer. I will check the vacuum and then follow this procedure. thanks for the details.

[@multidimensionalexploratio3985]

One of the better videos I've seen on this. Thanks for posting!

[@davewilliams4556]

Great video! especially the warnings about charging vapor as opposed to liquid! Thanks for mentioning this! locking up the compressor is very possible by turning the can upside down and flowing liquid into the system.

[@rosshoover6986]

Liquid is non-compressible. Vapor is compressible. The compressor can not handle the pressures built-up by squeezing a liquid. Something is going to bend 🤔 .

[@coldfinger459sub0]

That was a better video with more proper explanation than even the big famous channels who get over 1 million views. Great narration and clear and detailed explanation of how everything works. I very rarely give anybody a thumbs up on their air-conditioning videos but yours deserves one 👍. I definitely have to improve my video editing skills I just shoot and go with no editing. I have very unprofessional video shots just learning how to use KZbin and shoot video.

[@johnhub9626]

Thank you! Such a complete and easy to understand video!

[@thomas4362]

Absolutely fantastic you filled in many of the blanks from others .. GREAT JOB!!!!!!!! Thanks

[@mytube3043]

Without a doubt one of the best youTube instructional videos ever. Period. I've viewed countless DIY and instructional videos and few, if any, even come close.

[@humsup808]

Great video...Big help in my charging my AC. Thanks!

[@aldiaz6651]

Excellent illustration and explanation👏👍

[@davecc0000]

Thorough, methodical, and well edited (and excellent job of adding important audio comments later). Good steady camera work too. Top marks!

[@ollieoctopus1644]

Very good video. Many have the camera going all over the place, but your video was great as was the explanation.

[@WV591]

Good point on valve up and valve down on cans. TU..but i have never ever seen or heard of anybody charging with high side open. even if compressor not running.

[@appleSUX1]

bushougoma, I'm working on a 1998 Pontiac Trans Sport mini van A/C. After installing brand "NEW" A/C compressor(WITH OIL) AND a "NEW" dryer, I used a vacuum pump exactly as you mentioned. I also replace all the o-rings in the system( FYI, this mini van already has NEW hoses). After vacuuming the system for 1+hr, and testing air leak for 10+ hrs, everything was perfect with no leak whatsoever. So, it was time to fill the system just with 3 mall R-134 12 OZ cans. At first, the 1st can would not even go to the system. After several tries, it finally started to go in using ONLY the LOW side with hi side OFF(as you mentioned). After several min 1st can went empty with A/C clutch finally engaged. So I close the blue hose valve and replaced the can with the 2nd r-134 12 OZ can(with bleeding the system as you mentioned once more). However, for some reason the 2nd can will NOT go in the system at all no matter what, even with A/C compressor clutch engaged and working. NOTHING from the 2nd can is going in and I do not see anything flowing in that small glass above the yellow line. Do you have any suggestions as to what might causing it not to suck in any more(FYI, I ONLY use one 12 OZ can so far, I was told it will take 36 oz's, OR 2 LB of R134 as it shows on the sticker in front of the car). Also FYI, the blue gage shows 35psi and that's it. I'm puzzled. Please help:-) thank you very much in advance.

[@marinaparry1807]

Thanks for a good video, especially because I wanted to make sure that the guys knew what they were doing when they need to refill my AC..(might be a female watching them..but now I know what to look for and which questions to ask)

[@roxanadolh7569]

Very good video,easy to follow.Please keep posting.

[@rbarr1200]

Excellent video excellent editing. Thank you

[@laellewis7787]

THE GREATEST PROFESSIONAL VIDEO OF HOW IT REALLY WORKS

[@otislawrence474]

I am a beginner with an interest to know more about auto AC. I have looked at several videos but this one is the most informative. Thanksssssss. I have subscribed to this channel. Thanks.

[@d.mc.6434]

Way cool! Thanks for posting the video.

[@microphonixvirtualstudio1634]

This is good! Looks like you did it correctly.

[@496elcamino2]

Nice professional explanation, doing mine tomorrow.

[@nicorallysport]

Super vidéo 👍, très très bien expliqué ! Bravo 👏

[@mailmanjoe]

Hey busho! I love referring to your videos for the cd5 accords. They're so precise and detailed and of course helpful! I've been meaning to ask, were you ever a Honda tech? I ask because my dad was and you know very precise things about these accords. Stuff that the average person wouldn't like all the little quirks the car has. Thanks for your awesome videos!

[@HouseOfStrength]

Great video. Thanks for all the information.

[@3929tube]

Liked your video ben working on my a/c on my truck for a couple days. I had to order pump. anyway I have watched a lot of videos in the last few days I found yours direct to the point. very cool. the only thing I don't have is the digital scale.

[@papi352583]

Thumbs up @ 12:10 for how to purge the yellow line. That helped me choose a nice affordable manifold set without the purge valve on the yellow hose.

[@andresmurillo5117]

Good job.Thank you for the information....

[@nicklavorata1653]

excellent video. very informative. thank you.

[@kugmyster]

Great video, loved your little Smurf hands too.... Thanks!

[@johndaniels4108]

Very well done THANKS Mate

[@aminammar4260]

What agreat work The most proper vid I have ever seen 👋👏👏

[@salmanalmahal5373]

i like your video i give it 95% thank you very much

[@pg9112471]

Best car AC vid. Thanks.

[@gmcjetpilot]

I was not sure about pre charging a vacuumed down system a little before starting. All the other videos have you start with a vacuum on it. I will follow your process. I am over thinking it... but thanks again for video. I am about to replace the RCV (refrigerant control valve) on my VW A/C compressor. This type of compressor does not have a clutch like most. It always turns but is variable internally. The RCV varies the swash plate and piston travel. These valves can get stuck and not operate properly.

[@MrSamrisutir]

Good Video. Clear explanation.

[@henrietn]

Excellent tutorial. Thumbs up!

[@cesarorozco2462]

Yes, and the video is very clear.

[@davidpearce8829]

Great clear instructions THANKS

[@Southernshaker]

Excellent video, thank you.

[@MrKilo20]

Thanks for that video it was very helpful and how you explained it thank you

[@mfigueroa1112]

Excellent video, Thanks.

[@smms1276]

WELL DONE THANK YOU, 👍

[@sedona1378]

The quality of this video is the best. I learned a lot. I look forward to one that discusses how to correctly and legally discharge a fully charged system using a refrigerant recovery machine say when converting an R-12 unit to R-134a. I have a question about my Robinair MVAC R-134a charging manifold. The middle of the of the manifold bar has the standard 1/2 inch male acme port for attaching the yellow charging hose. However this manifold is different in that this charging port fitting is actually a T-fitting that has two 1/2 inch acme ports, the second 1/2 inch acme fitting is located just below the sight glass and at a 90 degree angle to the one used to connect the yellow charging hose which is pointing down. This second port is also I/2 inch acme has a black cap and has a shrader valve core installed. This connector is not to be confused with the two blank connectors that are located at the ends of the bar and made for hanging the red and blue hoses to keep them out of the way. What is the purpose of this shrader port? I'm thinking maybe it is designed to be used in conjunction with a vacuum pump and a ball valve to pull air from the manifold and hoses just prior to charging the AC system. Thank you.

[@frankl1955]

Excellent video, clear, concise, and complete. Thank You.

[@augustmelinda304]

Very good video. You explained it in very good detail. I just found you and going to look and see if you have a video on a Full recovery on our R 134 A

[@seshachary5580]

very educative. Thank you regards

[@CHIBA280CRV]

Fantastic informative video thanks

[@vernonlevy1447]

Very good and informative video. I would have liked to see the link for your scale. Thanks for the video.

[@thisisyourcaptainspeaking2259]

Good job, done correctly.

[@themusj]

Excellent video. Clear, Precise and very Helpful. One question has crept up on me related to recharging. PAG46 oil. On my 2001 Caravan, one site says it holds 13 ounces; another 7.4 ounces. The compressor itself says it holds already 5.4 ounces and to add 4 MORE ounces if the vehicle has rear air {which mine does.} That would be 9.4 ounces. I added .8 ounces to the dryer, and 1.5 ounces to the condenser. Assuming the evaporator still holds 20%, what if any oil do I really need to add? Who is right?

[@kaibigan3nimysuperboss682]

Napaka angas naman po niyan lods grabe naman po yan

[@IAcityntv]

Good video thanks!

[@diulaylomochohai]

what kind of manifold set do you have? whats the exact mastercool model you got? I am browsing on amazon and i only see "manual/standard couplers" - i guess these couplers automatic depress the shreader valve when you connect? My Honda a/c isn't cold. I see some "dried black carbon looking" stains on the condenser. does it sound like a slow leak freon stain? can you also explain how to properly inject a dye into the system? great video

[@robstuewe4336]

Great video, lot of great points that many other fail to mention or show as part of the process. I will be replacing my condenser along with dryer and orfice valve next week. I know I will be needing to add oil to the system but is there any way to know or calculate how much to add, since I'm not doing a compressor swap there's no way for me to flush out all of the oil and start over.

[@Bushougoma]

Most manufacturer service manuals will tell you how much oil to add after replacing a specific component they will also specify the type of oil and viscosity. Follow the manual recommendations for adding oil to the new compressor it usually involves draining the old compressor and measuring the oil removed.

[@Jaredlindo55555]

Great video~!

[@markpatterson7070]

Great video!!!!!!!!!!!!!!Thanks

[@CaracCompressor]

good job

[@stijnkegelaers653]

verry good video thx for scharing

[@dieselrotor]

Just curious, but after watching a few these self help vids. Why does no one ever check the deep vacuum 1 micron moisture content especially after an open ac situation ? At least You mentioned a moisture possibility, good job.

[@MichaelA-xx2ls]

Great video Bushougoma! Question, Would you do anything different than seen in your fine video if it was for a newly installed variable displacement type compressor with expansion valve type system? Any thoughts on this?

[@foreverwood1963]

That was a damn good video

[@albuzon9375]

on segment time 13:49 was the portion say open the two lines ( low & high side ) ? Great video just want to follow if I hear you right . Thanks

[@marotidapke3900]

Very good pictures

[@sivucit]

hi, hope you are good. i always keep your videos as baseline to come back and check , years after i have doubt. great video, .. i was working on a car today 08 chevy sedan .. i see that low side is around 70 coming back to 60 and high side is 130. compressor kicks and clutch engaged.. i assume it is compressor is bad and not TXV stuck open, is my assumption right. pls advise.

[@NOEISY1]

Thank YOU

[@joelcmanarang9886]

thank you very much

[@66crush9]

Love your videos! I do wonder how you would know if the manifold gauge set itself is not leaking rather than the A/C system?

[@davidgreen7501]

Very informative and very well presented.Watching the film I was wondering about discharging the system and where you did it, but then I realized that the AC system was empty when you vacuumed it. I assume then that two refrigerant bottles are required, one to collect the used refrigerant from the vehicle AC system and one bottle of new refrigerant to charge the AC system after vacuuming. I did notice however that during the presentation you advised about turning the refrigerant bottle upside down during filling the system I think, but then you did not turn the bottle over but used the vehicles AC compressor to charge the system. I do however have questions like have you produced a utube that shows and explains to us how you discharge the system and how you measure the amount of oil removed from the AC system etc. I hope you read this and point me in the right direction to more of your utube examples thanks David

[@davecc0000]

+David Green Reclaiming refrigerant can only be done with a dedicated reclamation system by a licensed pro. Not recommended for the DIY'er. Once the refrigerant is removed, the system is empty, at 0 psi. Then follow Bushougoma's video.

[@kmechkmechanical6658]

Great video. Covers the fundamentals very well. The most important part is: you told the audience they need to weigh their charge into the car. I have a 1995 Accord V6 which I recently replaced the compressor, dryer, condenser coil, evaporator coil and expansion valve. The system held nitrogen at 100 psig for one hour and full vacuum for 24 hours. No leaks. I charged the car with 21 oz as noted on the label of the vehicle. I use a Robinair charge cylinder to measure my refrigerant charge. Once the vehicle was charged the compressor engaged and the car begins to cool. Both fans are operating at the radiator. No short cycling of the compressor however, I cannot get delivery air temperatures below 70F from the dash grills. All doors and windows closed and the car is in the garage with ambient conditions of 86F and 77% RH. This morning the static pressure is 75 psig at ambient conditions of 77F. At idle the low side: 21-28 psig, high side: 125 psig with compressor engaged. At 1500 rpm the low side: 15-20 psig and high side 140-150 psig. The pressures seem low. Not sure if I have a bad thermistor or bad remanufactured compressor. Any suggestions?

[@Bushougoma]

KMech KMechanical How much oil did you add to replace the lost oil in the old components? The service manual tells you how much oil to add based on which components you've replaced. You have to use the right oil Honda recommends ND8 which is a factory part number. PAG 46 is it's equivalent. PAG is the oil type 46 is the viscosity. Why was the old compressor replaced? If it was due to mechanical failure you need to flush the aluminum lines to prevent debris from destroying the new compressor. Based on all the components you've replaced the oil in the system will be minimal so I hope you didn't forget to add it.

[@kmechkmechanical6658]

***** Very good point. I thought that I initially over lubricated the system the first time causing a 'fouling effect' on the cooling coil. So I flush cleaned the evaporator coil and condenser coil but did not add addition oil. I have a Honda service manual I purchased from Helm with the recommended oil fill for each component. I will go back and add where needed. The compressor was properly filled with PAG oil. It is my understanding that you need the proper amount of oil in each component along with the correct charge in order to achieve the proper pressure readings?

[@Bushougoma]

KMech KMechanical As long as too much oil isn't added it doesn't matter where it's put in the refrigerant will evenly distribute it throughout the system. Did you insulate the sensor bulb on the expansion valve with prestite tape? It needs to measure the temperature of the evaporator outlet tube and not the air blowing past it.

[@kmechkmechanical6658]

***** I did not answer your other question. My apologies. The old compressor did not mechanically fail. I had a problem with the cold system cooling. I initially replaced the thermal expansion valve, pulled vacuum and recharged. The car never cooled below 65F. In the summer when it was 100F outside it could not keep up. The car is an old salvage I acquired three years ago. At the time it cooled great. Since I had no history on the vehicle I decided to replace the HVAC system this summer. Its my commuter car to and from work. I did flush the all refrigerant lines with a flush gun and flushing agent for automotive systems. All of the lines were dry when reassembled. The dryer remained sealed until final installation to ensure it was not CV compromised. The new compressor has not run too much so hopefully nothing is damaged.

[@kmechkmechanical6658]

***** I did not use prestige tape however, I did cover the bulb well with foam insulation used on copper refrigerant lines. Felt that I insulated it well from the air stream.

[@ionracer24]

Thanks for sharing with all those neat toys u have hehe ;)

[@MRM-wp4gr]

Actually you can be just as accurate using the small cans by using a small digital kitchen scale. Same procedure....just zero out the reading with a full can and keep track of how many grams go in. Good video

[@Bushougoma]

The weight of the charging line relative to the weight of the can will skew the readings. It's very difficult to get the can (and the line) to stay put in the same place on the scale especially as it empties. The charging line will actually cause the can to tip off the scale at a certain point. Any shift in the position of the can on the scale will compromise the accuracy since the weight of the charging line in this new position will be different and skew the reading.

[@MRM-wp4gr]

Close enough for me. I didn't have a problem since the yellow charge hose is long enough

[@glen7850]

I might tape my small can to my small scale when I charge my system and have the scale off the vehicle on a stand so no vibrations

[@tyrc12pro94]

@@Bushougoma so if the system says 48 oz you can't put the 48 oz in and be ok?

[@H7s7h]

What is the best pressure for the gas in home split air conditioner? Thanks

[@sameermohammed2657]

If you don't have a Cale how can you tell if it had enough refrigerant will the low side needle not drop at a certain point ?

[@rvelandi1919]

Great video. When vacuuming an empty system does the oil pag is also removed? Considering that no new parts are being replaced, and I am doing the vacuum just to clean the system and be able to recharge it. Should I add more oil?

[@Bushougoma]

A very small amount may but it's nothing to worry about. As for adding oil check your service manual. Some manufacturers will tell you to add a certain amount of oil to compensate for the oil lost due to a leak. If the manufacturer doesn't have a recommendation for leaks don't worry about it.

[@akudosolarsystemprincechib5571]

Nice one

[@smms1276]

Any recommendations on vacuum pumps. Such as size, cfm or anything like that?

[@johnibrahim7283]

Nice Video! If I want to hook up the AC manifold to your car to do some measurements for the pressure, should I purge the blue and read lines from air once I connect them or no need as the air will not get into the system? please clarify thx

[@athersheheryar689]

hi, i hope you will be doing well. What about estimating compressor oil amount in the system while taking the gas out and putting it back into the system. Thanks

[@oliverrefrigeration4851]

Gud work

[@vboss5764]

They should make a tee valve so you can have the vac pump and freon can hooked up at the same time, when your done close off the valve to the pump, and open freon.