Getting the A/C to blow arctic cold

[shamanie]

My situation is this: I don't know whether my A/C needs a recharge or to be completely replaced.

The A/C just doesn't blow cool air. My grandparents, from whom I bought the blazer, seem to think it never really did.

What would you guys recommend?

I don't want to take it in and be told..."Welp, looks like we're gonna have relace the engine" type mumbo jumbo.

If it needs to be replaced, how much am I looking at and where should I get it? Where should I take it to have the work done? Same place I usually take it to? Or perhaps someone who specializes in that type of work.

Thanks.

[TimK]

It is possible your system is just low on refrigerent. With all the vibration and temperature variations a mobile A/C system sees, it pretty common for them to lose a little gas every year on a system that is normal. I see 3 ways you could go about this. The first one you already have started. It's possible someone on this forum or you might know someone who can recommend an A/C technician you can trust. The second option is you can learn about how your A/C system works and then when you do take it to a shop you will know when they are giving you a load of crap. The third choice is you do it all yourself.

If you want to get some reference material on how A/C systems work and a set of guages so you can test your system, then check out WWW.AAPAK.COM (http://WWW.AAPAK.COM) . They sell A/C kit's online along with guages and reference material. I would highly recommend a book they sell for $20.00 called " Automotive Air Conditioning Basic Service Manual". It describes most of the mobile A/C systems out there with a lot of emphasis on US manufactures. The system used on my 85 Suburban is in there and I am pretty sure it will be similiar to your Blazer. With a set of manifold guages and a thermometer you can do a lot of you own diagnostics.

TimK

[Dieselboy]

Check the vacuum actuated vent door under the screen assembly directly in front of the windshield. My door recently broke, and I couldn't get the temps below 72. With the door fixed (closing fully) I can run as low as 60.

[Peter J. Bierman]

There are a few things you can find out your self:
First, if its only a air vent door you shout hear the compressor kick in once you turn on the A/C.
If you not hear a klick and a little lower RPM at idle, the compressor is not working.
The compressor should get like 12 volts on the lead from the magnet clutch.
If you get the power, the clutch is broke.
( all you see at the front off the compressor should turn if working, not just the pulley )
If you do not get current, you might be low on charge or the pressure switch does not work.
On the tin can thing on the pass.side firewall is on one side the pressure switch and on the other a valve with a cap on it, ( the valve looks like a tire valve )
On the switch are two wires, on one off them you should have 12 V when A/C is on, if not, check the fuse and A/C dash switch, if you have the 12 V,you are low on charge or the switch is broke.
To find out if you have any charge at all, push the valve in a little to see if any refrigerant comes out , ( BEWARE this refrigerant can couse serious burns when in contact with your skin :eek: )
If there is anything comming out, you have at least some charge and the most likely thing is the switch.
You can replace the switch without recover the system, its just screwed over a valve witch closes as you unscrew the switch.
If a new switch does not cure the problem: :(
Go the the A/C shop and have the refrigerant recovered and the system pressure checked and recharged.
If no leak is found, have them put in FLUO DYE so you can discover any existing or future leaks easy with UV light. :rolleyes:

If you do this you have done all you can without making a lot off costs and tell the shop just to recover and leaktest and recharge. smile.gif

Hope this helps,

Peter

[doncannon]

shamanie,
When I was a partsman (not so long ago) someone told me that if the a/c is not blowing cold then it has a leak. That said it could be the o-rings and hopefully it is. When we had our Monte Carlo recharged he said it probably would not last long however he did put the die in it to find the leak (as peter has said). A week later it was not working and when we took it back he said it was the compressor. I know what does that have to do with your Blazer...well 2 points. He said that compressors are a common occurrance in GM products and second we checked him out and he was a good repair shop (with local auto parts and friends)as TimK said.
just my 2 cents worth,
Don
Oh maybe others could suggest converting to R134 because I remember the R12 prices are really high and it will probably leak out the first time (I hope not). Hope this helps.

[shamanie]

Wow, thanks you guys. I will get you an update as soon as I can.

Shamanie