A/C barely cools
Thread Starter
Racer
Joined: Jun 2001
Posts: 309
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From: Louisville
A/C barely cools
I did a search and found many good ideas but none that worked for me.
I serviced my a/c last week. I replaced the heater valve, drier, front and rear expansion valves and all o-rings associated with those components. I took it to the shop and had them evacuate, leak check and fill with R-12. It worked ok- seemed like it should have got colder. Today has been a week since the service and it was not cooling as efficiently as it was. With the car parked the a/c does not get cold, not even cool it just stays warm. I adjusted the temp mixer flaps on both sides and was expecting colder air but it wasn't. I have to drive a few miles before the air starts to get cool and that is as far as it goes- just cool. The inside of the car never gets cold. The rear a/c seems to be the same temp as the front. I checked the recirculation flap- functioning. The heater valve is working and is not installed backwards. When I look in the drier window with the engine off I can't see anything (don't know if I should) And when the engine and a/c are on I can see the fluid movement but there are white bubbles. Also after the a/c was serviced the rear a/c would periodically make a hissing noise, maybe the expansion valve cycling or something? Anyway now it does not cycle instead it continuously makes the hissing noise. I don't know if it should or not. It's an '86.5. Any ideas are greatly appreciated.
I serviced my a/c last week. I replaced the heater valve, drier, front and rear expansion valves and all o-rings associated with those components. I took it to the shop and had them evacuate, leak check and fill with R-12. It worked ok- seemed like it should have got colder. Today has been a week since the service and it was not cooling as efficiently as it was. With the car parked the a/c does not get cold, not even cool it just stays warm. I adjusted the temp mixer flaps on both sides and was expecting colder air but it wasn't. I have to drive a few miles before the air starts to get cool and that is as far as it goes- just cool. The inside of the car never gets cold. The rear a/c seems to be the same temp as the front. I checked the recirculation flap- functioning. The heater valve is working and is not installed backwards. When I look in the drier window with the engine off I can't see anything (don't know if I should) And when the engine and a/c are on I can see the fluid movement but there are white bubbles. Also after the a/c was serviced the rear a/c would periodically make a hissing noise, maybe the expansion valve cycling or something? Anyway now it does not cycle instead it continuously makes the hissing noise. I don't know if it should or not. It's an '86.5. Any ideas are greatly appreciated.
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Joined: Jan 2004
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From: Boulder Creek, CA
Do you mean it's not working as good as it did a week ago, or not as good as it did before the service? Either way, you might have a word or two with the shop that did the work so they can double-check it. Can you put a thermometer in the center vent and record some observations, e.g. temp at speed, stopped, etc. Also, make sure that the belt is not slipping.
Thread Starter
Racer
Joined: Jun 2001
Posts: 309
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From: Louisville
It is not working as well as it did a week ago and even then it was not working as well as it should have. Before the service it was inop. The belt is not slipping. I suppose I could locate a thermometer but until I do I can also supply a vague reading: at speed it's cool but not cool enough to cool down the interior. When stopped it's warm like the outside air. What a pisser.
Fleet of Foot
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From: We are there!(San Diego)
Sounds to me like you have a leak in the system, you are losing R-12. The hissing noise you hear is an indication of low refrigerant level... mine did the same thing.
Race Director
Joined: Sep 2004
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From: Stockton, CA
It does sound like a leak? What year is your car? Also how long was the system vacuumed down for...could be too much moisture in the system causing a reduction in output? But a new drier should have fixed that? How much volume of air is coming out of the vent? Maybe the fan is fading?
Brian
Brian
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Thread Starter
Racer
Joined: Jun 2001
Posts: 309
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From: Louisville
Car is '86.5. The leak test they perfomed involved some type of probe that detected... hydrocarbons? I was not aware all hoses needed replacement when staying with r-12 and the shop owner did not mention anything about changing them. It was vacuumed for ~20 minutes. A lot of air is coming through the vents, a lot of not cold air. Thanks for the tips.
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Fleet of Foot
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From: We are there!(San Diego)
Agreed Dave, should be a minimum of 30 minutes and the system should hold at least 29-30" of vacuum for AT LEAST 30 minutes. I can see no way that your system could have considering how quickly the performance degraded.
Race Director
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From: Stockton, CA
Originally Posted by SharkSkin
20 minutes is nowhere near long enough if it was inop for any length of time. In fact, that's not long enough PERIOD.
Brian
Thread Starter
Racer
Joined: Jun 2001
Posts: 309
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From: Louisville
This is all good information. I think a visit to the shop on Monday is in order. Just for clarification... consindering the symptoms do you guys thinking I still have a leak or moisture in the system? Or is there simply no way to tell at this point. Thanks again for all the info.
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Joined: Jan 2004
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From: Boulder Creek, CA
No way to tell for sure. However, the system was not vac'ed down per proper procedure. Whatever the reason, there is not enough r12 if you are seeing bubbles in the sight glass. Anything more is pure speculation. For example, I could just as easily speculate that the sytstem is leaking, or that the tech did not account for the extra freon needed given that you have rear AC. Doesn't mean much -- get it checked.
