DIY AC recharge, learn me.

'03 Accord, last year's cold AC is now a warm breeze. Looking for any advice on AC recharge cans. The directions on the can seem strait forward, any helpful hints from the GRM brain trust. A $27 can is better than taking it to the shop for $99.

your looking for 28 psi to 40 psi on the low side while system is engaged. if system is completely empty get it done professionally and fix the leak while your at it. if just topping off your ok.

Recharge without a successful vacuum is just pouring money into a leak.

I've done it, though.

friedgreencorrado wrote: Recharge without a successful vacuum is just pouring money into a leak. I've done it, though.

Not necessarily true... that stop leak stuff can work wonders. Maybe not on every leak, but I had a Volvo once that took two cans (a couple of weeks apart) and never leaked again after that. The A/C was arctic.

I would invest in a cheap manifold set. HF has them for something like $36. That will tell you a lot and also make it easy for you to vacuum, recharge, and diagnose in the future.

You need to make some preliminary observations; i.e. is the compressor kicking on? Is there any charge in the system at all? (test by briefly pressing the schrader valve with a screwdriver).

The manifold set will tell you tons. Run the engine at around 1500-1800 rpms. High side should be hovering around 275-300 psi depending on ambient temps. low side should be 25-40 psi. If those numbers are off, it tells you why. If the high side spikes it might be overcharged or have a clog. If the high side doesn't get very high and/or the low side doesn't get down low enough you might have an undercharge or toasted compressor.

The other way to do it is to get a can and put a little in at a time until it gets cold. Then rev it up. If the compressor kicks off you went too far. If it doesn't, count your lucky stars and drive on.

Diagnosing and repairing A/C without manifolds is like doing it blind. Of the several hundred problems you could have, recharging without a gauge set is only going to work if the one problem you do have is a leak/low charge.

Depends on the vehicle, some late GMs have only a high side port. That can't be done w/o an ac recycler.

Wife got home and tossed me a can of r134a and said fix it. I first checked other things, fuse, compressor working, ect, and all seemed good. Pressure with the system running was nil, so I recharged it and it was nice and cold. I will check it again after a few days.

A happy wife is a happy life.

purple what vehicle? this is news to me i have never seen a car that only has a highside service port?

In addition to a guage set might as well get yourself a decent vacuum pump. Also visit the good folks at ackits.com. They have a good forum.

In reply to curtis73:

Thanks for that. I got one of the HF kits but have not used it yet. One thing though, it looks to me like the connectors on my car ( 03 9-5) are different than the ones on the Manifold kit. Is there something else I need to buy or am I just blind and need to look at it again?

rusted sounds like u have a r12 kit

When they say "don't tip the can" they mean it.

In reply to KATYB:

Thanks. Back to the store.