How To Recharge an AC System - EricTheCarGuy

This video can show you the basics of recharging an AC system. I would urge you perform safe practices when working with AC and avoid venting refrigerant into the atmosphere. That said, with a little time and patients, you may be able to recharge your AC system yourself.

For more information on HVAC Problems.

Tools

As I said in the video you need to be responsible when dealing with refrigerant, also in some locations it's not legal for you to perform your own AC work so keep that in mind and observe your local laws.

Stay dirty

ETCG

Due to factors beyond the control of EricTheCarGuy, it cannot guarantee against unauthorized modifications of this information, or improper use of this information.  EricTheCarGuy assumes no liability for property damage or injury incurred as a result of any of the information contained in this video. EricTheCarGuy recommends safe practices when working with power tools, automotive lifts, lifting tools, jack stands, electrical equipment, blunt instruments, chemicals, lubricants, or any other tools or equipment seen or implied in this video.  Due to factors beyond the control of EricTheCarGuy, 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 EricTheCarGuy.

[Lockemeister]

Because of the small molecule of R134a, the refrigerant can commonly leak past the Schrader valves, especially the high pressure Schrader valve. The "dust caps" are actually an integral part of the entire system (per the EPA), being the last line of defense, so to speak, between the refrigerant and the atmosphere. There is a seal in the inside top of the cap that seals the top of the Schrader valve to theoretically seal the valve if/when the actual valve insert leaks. The "dust caps" need to be inspected for cracks and hand tightened to secure the system. Just wanted to mention that in case some folks think they are optional.

[Chris-imrd]

Eric. Know that your old AC videos are still helping people like me today.

[mrfixit]

And 12 years later this video is still helping. I had watched a few videos a couple months ago, bought all the gear and just lost interest in getting this done. Eric, you made this so much more simple than others. My daughters have A/C again. Thank you!

[MisterRisk]

Thanks Eric. I have been repairing my own cars for 25+ years. Engine rebuilds, drive-train, suspension, even body and paint work now and then. There were a few things that were voodoo to me, welding and A/C. 10 years ago I started taking welding classes at the local community college and now I can weld anything I want. I've been watching your videos for a little while now and finally decided to get a set of a/c gauges and a vacuum pump. This video was my guide to my first home A/C repair and recharge. You are bringing knowledge to thousands of people and the comments enhance that by bringing in even more thousands of knowledgeable people to add to and acknowledge the information you impart. It is amazing.

[joeg.cintron]

I viewed your video last week several times and took notes. Saturday morning I replaced my Jeep's A/C Compressor that took, surprisingly, one hour - remove the old and mount the new. Taking a break from the exhausting heat (we live in Florida), I once again viewed your video. An hour later, back into the heat and following your time line, I was finished in 1 1/2 hours. Thank you so much for an excellent, well throughout and easy to understand video. BTW, I saved $225 in the process including the gauge manifold set. [I was quoted $422 for the job, including tax.] I am now looking over some of your other videos - just in case. God Bless!

[patbrock]

Great video, the center hose is called the charge hose, I noticed that when you introduced freon through the charge hose you didn't bleed the trapped air inside the hose, usually you need to bleed just a minor amount of freon to remove any air in the line. But great job all around.

[tomboytomgirl]

Excellent video, Eric. Retired aircraft mx/engineering tech here. I like that you address the seemingly 'obvious' details. It's the little things that get you! You're absolutely correct: a/c systems are not for the faint of heart. Consequently; this should always be an "A/C for Dummies" course. You've done that. That's what makes you so good as an instructor. (BTW; I love "for Dummies" books/vids.) Remember; always keep on addressing all those little things (like the O-ring missing on a fitting; NEVER open the hi-press valve; safety glasses, etc.) that guys/females are too shy to raise a question about. Thanks and keep up the excellent work!

[guestguide]

What I found by listening to ac experts is low side pressure is ballpark of 1/2 ambient air temperature and for high side 2x ambient air temp. So adding refrigerant at 80 degrees ambient temp low side would be about 4o and high side 160. At 100 degrees low side 50 high side 200. They have stainless steel injector plungers that allow adding correct oil right at low side hook up. When I charged mine last 5 yrs ago I believe I added just under 2 oz oil with the oil injector, could have added some leak detector with it but hadn't thought to do it.

[cyberkiller]

Eric. I love your videos, i am not a mechanic by trade, but your videos some years ago gave me the little push that i need it to work on my own AC and get the tools.

Now i work in my AC and my friends AC, i had changed compressors, valves, hoses, and obviously recharges.

Now regarding the pressures that you get, my little experience had shown me that, the high side compression depende on various things like your said.

* The AC Compressor power or status, i mean, a bad compressor will give your lows pressures on high side and some noises
* The condenser debris or clean status, if its not too clean, the temperature will rise, rising the refrigerant pressure more than nominal values (i had that case on my fathers car))
* The charge quantity, if it is overcharged, you will see higher than usual both high side and low sides pressures
* Finally the ambient temperature.

On various cars i found there is a table with related the high and low side pressures in function to ambient temperature, i use those to diagnose my charge, i want it to be close, and, the weird part with your video is that i think is a little too low on the high side, like there is missing refrigerant still, because normally you will see on very chili days (about 18 degree) a low Side of about 30psi to a high side between 130 to 160 psi.

Maybe your day was colder that 18 degree, this way, that pressures will be pretty perfect.

Here in Medellin Colombia i have a ambient temp of about 30degree and that gives me a nominal low pressure of 40 to 50 psi to a high pressure of 250 to 270 psi.


Another tip that you maybe forgot to mention is, when you apply die or oil or ven the R134a gas to the system, you should purge a little bit the INPUT HOSE (i think that is the name jeje), so there is no air, moisture aggregated to the system.

Again. Congratulations on your videos, i love them very much, i used this video as a start on the AC world, and i love every minute of it, i used too the brake pad change video, i even used my vacuum pump to vacuum by brakes while charging, i love to learn all about this and do your self a lot of stuff.

Thanks Eric.

P.S: Pardon my english, my primary language as i mentioned in another comment is spanish, so... i love english but i am nowhere an expert on it.

[clausgraf]

Replaced the condenser in my Dodge Durango last week, pulled a vacuum and recharged it. It is working now! Watching your video made it very easy! Thanks, and keep up the good work & videos!

[JohnRBooth]

Dude,
You have fixed so many of my car problems.
Thank you sincerely
john

[fourstarrjim]

Great video, Eric! The yellow hose commonly referred to as the “Service Line”, because this lets you service the system. The adapter on the can is commonly called a “can tap”. Now there is a blue adapter for the can of refrigerant to prevent leaks, because the cans of refrigerant have their own shrader valves.

[theherbstep]

When you hook up the refrigerant canister YOU MUST PURGE THE YELLOW HOSE BEFORE CHARGING! It is done simply by the following: step 1: hook up yellow hose to refrigerant can. step 2: turn the can upside down and open the valve on the can so the refrigerant fills the yellow hose. step 3: at the manifold assembly briefly loosen the yellow hose until you get a small puff of liquid come out and seal it back. Then you can charge the system.

[shelbyandmargaret]

You're a very good instructor. I took notes and soon I'll buy the equipment needed to find links, repair and possibly recharge the a/c system on my 1989 Ford E150. After eighty dollars for a recharge and twenty dollars for a hose replacement I had a/c for four days. Two weeks of running back and forth because there was problems with getting another unrelated repair right the mechanic simply wanted to send me somewhere else to spend more money. At this point I figure I have nothing to lose by trying to figure things out myself versus going blind on the word of others and paying whatever they demand and coming out no better off.

[AceABCDN]

Hi Eric. I'm actually a professional career pilot, but my hobby has always been restoring cars, especially the older ones. Your videos are great. I maybe a little bit more of a perfectionist, but you definitely come across as knowing what your doing, and most importantly, you show and talk about even your mistakes or errors in your first judgements calls that makes you a really do it yourself kind of guy that all home mechanics can connect and relate to. Great work Man. And just a small plug, the only other repair videos that I watch on a regular basis it are Kevin Tetz, Hands-On-Cars. By combining not only both of your knowledge, but also common sense and attitude, there isn't anything I can't fix on a car or truck, in budget, and do it right the first time.

[mikeashford]

Eric The Car Guy, Thank you for the info you make it look all so simple ... I got my Ford Ranger down to -25 and it held vacuum for several hours so I put the R-134a in the system and it went smooth, , so no more driving around with the windows down

[havoc]

Eric, great video! It's called the service hose of the manifold gauge set. Keep the content coming!

[jeffpoppert]

Eric is an excellent instructor. I used many of his videos successfully. I replaced a compressor in a 2003 Elantra back in 2019 and used this video to learn how to vacuum and charge a system. The ac is still blowing cold. Thanks Eric.

[DjJtown]

I can't tell you how many times I've used your vids, especially this one as a reminder of the steps. With that being said --- see what I did there --- I just noticed your high tech audio. I cassette to CD adapter. Well, at least I'm not the only one. BTW, good luck on whatever you are doing and enjoy. You've been a great help and I shall say; in some cases; a great instructor. Thank You very much for sharing your knowledge with ALL of us.

[troyken]

I just did this this morning according to the video. I had the exact same symptoms and added R-134 as shown outlet temp dropped from 46 to 39-40 degrees F. Feels much better. Thanks for the helpful video!!!