A/c Condensor Overheating !!!!!
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Instructor
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From: FRANKLIN SQUARE NEW YORK
A/c Condensor Overheating !!!!!
HELP HELP HELP !!!!!!!!!!!I have a ' 76 that I dropped a '94 lt-1 into . My problem is the condensor " overheats ", and cuts off the a/c
. I have 2 electric fans that DO NOT go through the computer, but rather , are connected to 2 relays . One idea I had was to connect one fan through a relay that would be connected to the a/c harness. When the a/c is used, that fan would come on . As the engine heats, the second fan would come on and cool the radiator along with the first . When the a/c is off, both fans would work as normal to cool the radiator .
I hope someone has a better idea than this one . It's the only thing I could think of . .
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From: Florida
Originally Posted by WRAITH666
HELP HELP HELP !!!!!!!!!!!I have a ' 76 that I dropped a '94 lt-1 into . My problem is the condensor " overheats ", and cuts off the a/c
. I have 2 electric fans that DO NOT go through the computer, but rather , are connected to 2 relays . One idea I had was to connect one fan through a relay that would be connected to the a/c harness. When the a/c is used, that fan would come on . As the engine heats, the second fan would come on and cool the radiator along with the first . When the a/c is off, both fans would work as normal to cool the radiator .
I hope someone has a better idea than this one . It's the only thing I could think of . .
The more you cool your condenser the better your a/c will work.
Always use guages to diagnose a/c problems. You may just be building too much pressure.
Pro
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From: Boynton Beach Florida
on a 80 degree day the low side should be about 30psi and the high slde about 250-275 if the low side is lower it might need freon, if the high side is much higher you might have a blockage ( junk in the orifice)these numbers are for R12 freon
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From: FRANKLIN SQUARE NEW YORK
The compressor is a ' 94, so, it's using the R-134 .Someone who did this conversion told me to run the system at 20% less than the stock R 12 capacity . Sound right to you ?
I know DeWitts has special relays to work the fans with a/c, but, to rewire everything is a bloody nightmare. But, if that's what it takes, so be it.
I know DeWitts has special relays to work the fans with a/c, but, to rewire everything is a bloody nightmare. But, if that's what it takes, so be it.
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Joined: Mar 2006
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From: Florida
Originally Posted by WRAITH666
Ok then , if you think it's a pressure problem, what would . or should, the proper pressure be ? These are 2 different year a/c parts from different years .
The pressures are all relative to the ambient temperature. Here in 95* weather, I run 35psi low side and 235 psi high side and get 38* vent temp.
Both the evaporator and the condsenser have good air flow and clean inside.
If you have internal blockages and/or poor air flow you will get excessive psi and the high limit will kick off the compressor. It may be as simple as a blend door stuck. I have never heard of a "condenser overheating" but I am assuming this is what you mean.
I am taking this from memory so my figures may be a little off. Without a auxillary condenser fan the high side was 260psi, then turning on a 2400cfm spal pusher fan the high side dropped to 220psi.
Basically, without getting technical, that is a very good result and aids in better cooling and longer compressor life.
When you wire the fan for the a/c don't tag the compressor clutch feed or the fan will cycle with the compressor. Tag the a/c on from the dash control itself.
Unless you have an obvious problem such as a broken wire etc., you must take your temp and pressure readings and diagnose from there, otherwise you're just shooting blanks.
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Instructor
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From: FRANKLIN SQUARE NEW YORK
I contacted DeWitts and got the following as a fix to the problem . They said to get another relay, and connect it to my existing fan relays . Connect one wire from the new relay to the sending unit of the fans, and then connect another wire to the + 12 volt wire of the a/c clutch ( the colors are listed in the instructions ) . The fans will kick on when the a/c is used. Sounds a bit complicated , but it really isn't. Just a pain to rewire everything !! Again
Last edited by WRAITH666; Jun 25, 2006 at 04:52 PM.
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Race Director
Joined: Mar 2006
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From: Florida
Originally Posted by noonie
When you wire the fan for the a/c don't tag the compressor clutch feed or the fan will cycle with the compressor. Tag the a/c on from the dash control itself.
And besides, it is also just annoying.
Just use bosch type relays. They are industry standard.
They all wire the same.
http://www.mcminone.com/product.asp?...duct_id=26-534