Recharging vehicle AC


#1

Hey, curious if anyone here has done a DIY refill for their car AC unit? I’ve had my AC “recharged” twice for about $250 but my seals must have a slow leak, because after a couple of years it no longer works. Ignoring the environmental implications of dumping refrigerant into the air, has anyone done those manual refill kits? I’ve heard mixed things.


#2

It’s the same refrigerant as what the shops use, just in can form, as far as I know.

Modern refrigerants aren’t the ozone hole-causing CFCs that they used to be, so the environmental implications aren’t quite as bad.

Refrigeration systems like AC should ideally never need to be “recharged”, but in reality they do leak sometimes. Solve the leaks before you keep dumping refrigerant into your AC system otherwise you’re throwing money down the drain.

Source: have worked on some projects with a refrigeration technician, although not on car Air conditioning (the physics principles are the same though)


#3

There are some kits that have a UV dye in them that help you detect leaks in your AV room. You can then use a blacklight, and if your engine bay looks like the bedsheets at a sleazy motel then you know you have a problem with your AC.


#4

Yeah, both times I had it “recharged” they did the dye test and found no leaks, but it ended up leaking. Replacing the seals in the system isn’t really feasible or worth the money - it’s a 1999 - but I wouldn’t mind being able to refill the thing another once or twice and would prefer not to spend $250 each time.


#5

Yeah a diy recharge kit would be perfect for you then. Most people aren’t comfortable under the hood of their car, which is why the shops do it, but the diy kits are designed to be pretty user friendly.


#6

The nice thing about the kits is that you don’t need a whole refrigeration gauge manifold set which can cost a lot of money. The recharge kits typically come with all of the fittings you need and a gauge thingy.


#7

Ah, great to hear! Thanks!


#8

No worries. I haven’t done any car A/C work, but I’m sure YouTube would be your friend for this.


#9

lol - wish I knew about this back in my k-car days. Looks like recharging is pretty simple to do. :smiley:


#10

Since the early 90’s cars are filled with R134A and not the more efficient but ozone eating R12. Consumer kits to recharge R134A systems sell at retail stores in the USA but not in Canada. Princess Auto has kits up here that use very clean propane (literally propane) as the refrigerant (R12A). It has excellent performance but is also flammable in an accident. The oil in your car’s AC system may or may not be compatible with R12A.

One alternative to getting R134A up here is to buy it at RP Electronics: https://www.rpelectronics.com/402a-450-super-duster-compressed-air-mg-chemicals.html

You will need a can tap to get it safely out of the can: https://www.centurytool.net/10102_Side_Can_Tap_R12_R134a_Respective_Oils_p/ro10102.htm

And a gauge set to get it safely into the vehicle: https://www.centurytool.net/48134B_Robinair_1_2_ACME_Side_Wheel_Two_Way_Gauge_p/ro48134b.htm