need help with air conditioner

[JC1933]

I have problems unit works fine at start up lots of cold air as long as I don't shut engine down than al I get is warm air.I have had it in a shop twice they changed all the refrigerant fluid and also changed a valve,what should I do next? this is getting expensive.

regards J C

 

[ufm82]

Re: need help with air conditioner

Car? Truck? RV? Family room? LOL
Give up some details and we'll try to help. Make, model, year, engine, etc.

 

[WizeOne]

Re: need help with air conditioner

Car? Truck? RV? Family room? LOL
Give up some details and we'll try to help. Make, model, year, engine, etc.

Plus, a little punctuation might help as well.

 

[JC1933]

Re: need help with air conditioner

Thanks for the reply.

It is in a motor home, the engine is Chev.454 1993 year.
As I said before it runs until the engine is turned off,when it is turned back on only warm air.

I drove it 30 miles to day and it worked fine till I stopped for 10 min,and started back,no more cold air for the 30 miles back.

 

[waterinthefuel]

Re: need help with air conditioner

Sounds to me like the compressor isn't kicking back on.

Maybe a thermostat? I don't know. Maybe it's overheating? I'm not sure. I've never had this problem before.

 

[xxxflhrci]

Re: need help with air conditioner

So, when does it finally come back on?

We had a similar trouble on a 2000 Ford Escort. It would cool at an idle all day long. If you drove the car up to about 40 mph, it would shut off and not come back on until you cut the car off. I changed everything electrical in the system, including the control panel and could never get it fixed. All last year, it would not work properly. Then, like magic, it started working this year and is still working properly. Go figure.

Good luck.

 

[JC1933]

Re: need help with air conditioner

Thanks guys.

It comes back on when the engine is cool.

regards J C.

 

[SS MAYFLOAT]

Re: need help with air conditioner

It sounds like it is overcharged. When you turn off your engine, the heat from the engine compartment is boiling off the freon in the system opening the high pressure cutout. Try spraying water into the radiator when it is blowing warm air (with engine running) as this will cause the pressure in the system to be reduced resetting the high pressure cutout.

 

[DECK SWABBER 58]

Re: need help with air conditioner

When it was at the shop could they duplicate the problem?

Sure sounds like the compressor is not coming back on for
some reason. Could be as simple as a relay.

This should be a fairly easy problem to diagnose for a
competent a/c technician.

 

[nothreat]

Re: need help with air conditioner

I had the same problem in my Galant last fall and just ignored it (it was cooling off anyway). This spring it would sometimes work and sometimes not. I checked the low side pressure and it said I was low so I added freon with a Walmart kit. Then it did not work at all. I took it to the shop and they found that I had 500+ #s on the high side. They evacuated the entire system and recharged and it works beautifully now. I am amazed they system did not just blow apart and so were they.

 

[JC1933]

Re: need help with air conditioner

Thanks a lot guys.

I will take your recommendations to the shop tomorrow.


Regards. J.C.

 

[Vlad D Impeller]

Re: need help with air conditioner

Mayfloat hit the nail on the head. I once had this exact problem, it was due to the system being overcharged by an incompetent tech.

 

[SS MAYFLOAT]

Re: need help with air conditioner

I don't know how many times people automatically think they have a refrigerant problem and do the DIY thing to their car. All they are doing is introducing noncondesibles into the system with a possible overcharge. Then they still have their original problem along with a new one. When there are mulitple problems, it sure makes it a whole lot harder to troubleshoot what was wrong in the beginning.

Freon does not wear out or get used up. In school, I was taught that only 10% of the time in refrigeration and air condition that it would be a refridgerant problem. 90% is either mechanical or electrical.

 

[JC1933]

Re: need help with air conditioner

Good morning to all.

I think my problem is solved after $561.00 the problem was a check valve at the dryer canister.

Thanks guys. J.C.