AC not cooling
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AC not cooling
Just out of the shop last august, new compressor ,converted to r-134, now it doesn't cool. The fuse is good but the compressor wont start and there are no water droplets on the condensor. I read that there is a low pressure switch on most systems that prevent the compressor from turning on if the refrigerant is low. Any input would greatly appreciated. 87 bronco, 302.
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From: Coweta,GA, GO DAWGS!!!!!!
Bypass that lps and watch the compressor come to life.
You gotta leak! Hopefully it's just an o-ring and not a line or fitting or worse.
The only other thing that would keep the compressor from working is a bad compressor. Rods, base plates, or comp heads. I've heard the compressors have very short lives in the 12-134 conversions if the oil is'nt changed over or the system and compressor are not flushed very well.
You gotta leak! Hopefully it's just an o-ring and not a line or fitting or worse.
The only other thing that would keep the compressor from working is a bad compressor. Rods, base plates, or comp heads. I've heard the compressors have very short lives in the 12-134 conversions if the oil is'nt changed over or the system and compressor are not flushed very well.
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Joined: Mar 2004
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From: Texas
Originally Posted by crustyeagle54
Just out of the shop last august, new compressor ,converted to r-134, now it doesn't cool. The fuse is good but the compressor wont start and there are no water droplets on the condensor. I read that there is a low pressure switch on most systems that prevent the compressor from turning on if the refrigerant is low. Any input would greatly appreciated. 87 bronco, 302.
With the A/C switches off, you may unplug the electrical connection from the low pressure switch (location above) and place a short jumper wire (about 8" #14 THNN stripped on both ends) into the socket you just unplugged from the pressure switch. With the ignition on, engine run, select A/C max cool. The compressor should energize (clutch engage). If not, shut everything down and look for a bad connection. If yes, it is likely the low pressure switch is holding out the compressor circuit.
The only way to be certain if the low pressure switch is good, is to check the freon pressure with the compressor energized. If you are not familiar with this procedure, you should consult someone who is. Low pressure with the compressor energized may be a result of a leak, clogged evaporator orfice tube, or faulty compressor.
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Joined: Jul 2006
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From: Central PA
You sure they swapped out all the seals and new condencer at the shop ? If not r-134 will leak through old seals . In other words you can buy a kit at KMart to change over but will have to recharge yearly or more often. After 3-4 charges won't hold at all.
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bypassed lps, compressor starts . I didn't want to run it too long so I couldn't tell if it was cooling. There is oil underneath the front of the compressor. Its a reman. not new . Do they make a stop leak or something?
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From: Coweta,GA, GO DAWGS!!!!!!
The main seal in the compressor is blown if you have oil coming from the front behind the clutch. The best thing to do(although a pain and costly)is to replace the compressor,flush the system, and since you're breaking the seal on the system to replace the compressor, replace the orifice tube and the drier/accumulator.
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