need to recharge a/c [Archive] - Chevy TrailBlazer, TrailBlazer SS and GMC Envoy Forum

: need to recharge a/c


yungroyalty
04-22-2009, 11:20 PM
can someone tell me where the low side service port is, so i can recharge my a/c. thanks

MAY03LT
04-22-2009, 11:29 PM
year make model:undecided

yungroyalty
04-23-2009, 01:08 AM
2003 trailblazer ls

MajesticLT03
04-23-2009, 03:52 AM
Its located on the Accumulator (which is next to the radiator overflow tank).. find the black cap marked with an "L"

GMfever
09-01-2010, 05:39 PM
can someone tell me where the low side service port is, so i can recharge my a/c. thanks

year make model:undecided

How about a 2002 Envoy XL. Same place as posted before?

I see black cap on a line now, front left side left of rad. No L on cap though.

mypetropig
09-01-2010, 07:08 PM
How about a 2002 Envoy XL. Same place as posted before?

I see black cap on a line now, front left side left of rad. No L on cap though.

Go to the accumulator, back left corner of the engine compartment. The Envoys share the same running gear as TB's,.

4x4forLIFE
09-01-2010, 07:48 PM
Fatter line. Fallow the fatter line untill you find a black cap. Or if it works the cold one, which will be the fatter line.

GMfever
09-01-2010, 10:00 PM
Found another black cap on the silver round cylinder on back left engine compartment (accumulator)?

Then the one (black cap) that is in the line on front left of rad area (line is only about index finger thick).

4x4forLIFE
09-01-2010, 10:15 PM
Found another black cap on the silver round cylinder on back left engine compartment (accumulator)?

Then the one (black cap) that is in the line on front left of rad area (line is only about index finger thick).

Find the compressor. You should be able to and if you can't find the compressor.. turn on truck, a/c off, have someone go inside and turn the a/c on and look to see which pully makes the noise of the clutch engaging.

Ok now on the compressor there's going to be two lines coming out of it.
1 one will be fat and one skinny.. (this is compared to each other)
2 skinny line should go to condensor... the condensor is located in the front either behind or infront of the radiator. ANYWAY
3 the fatter line will go backwards towards the accumilator.

make sure your positive you got the suction side, or LOW side (fatter) line.
keep the can upright, that'll put vapor ref. into the system.
if you flip it over it'll put liquid into the system which as we all know a compressor is basically like a 1 cylinder motor so hence putting liquid into it will destroy it.

hope this helps if not try googling low side ac hook up on a 4.2 trailblazer engine. :tiphat

Robert1101
09-01-2010, 11:33 PM
You do have the guage set so that you do not overcharge the system and you do know what you are doing? 134A boils around 45 below 0 (depending on the pressure) and can give nasty frostbite burns.

4x4forLIFE
09-01-2010, 11:56 PM
You do have the guage set so that you do not overcharge the system and you do know what you are doing? 134A boils around 45 below 0 (depending on the pressure) and can give nasty frostbite burns.

Well I would hope he's getting the mini 134a tank and guage combo from advanced or auto zone.

Besides it's the vapor side he'll be hooking up the guages to. I don't have a tp chart handy but vapor won't harm you. Maybe the oil that sometimes comes out when you remove the guages on occasion if you have a cut on that hand might sting a little.

If he's either having that hard of a time locating it or is that nervous about the ref. I'm sure one of the employes there will help.

GMfever
09-02-2010, 03:39 PM
Never had to recharge a newer vehicle with 134 and just wanted to be sure. It all looks different to my old school mind set.

I have all the gauges for the older R12 set up and big cans (which is no good at this point). I was even one of the guys that put 134 in the old 12 vehicles as a recharge and never had any problems. I see some of them still working today at work.


I was just going to buy the tall 134 can and oil with gauges for this little deal.

No I'm not a a/c guy or a mechanic, just a shade tree hack that likes to know before :duh: it up.

4x4forLIFE
09-03-2010, 12:07 AM
That's fine you don't have to be a genious to do this. And honestly your better off getting the combo pack from Advanced Auto or Autozone. It's literally a 1L bottle sized ref. can with a guage hooked up to it already. Directions are on the back and you don't even need a temperature analyzer or know what the different pressures mean. All you have to know is that your hooking the guage up to the correct side of the system. there's a green zone on the can that your system shoud be in. That simple. If you want to go ahead and get a new set of 134a guages and a drum of 134a, that's fine too just make sure you know what you're doing. I'm not 100% sure myself but I do believe it's a subcooling measurement your going for.. which means roughlly a 9-13 degree difference between the high side temp on the guage and the temperature of the high side pipe before it goes into the condensor... while the system is running full blast...hope this helps..:tiphat