AC Compressor not engaging
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Joined: Jan 2015
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From: Surf City USA
AC Compressor not engaging
I just bought a 1982 Corvette and the AC compressor is not engaging from the control switch. I checked for blown fuse already. Can someone recommend a way to bypass the control switch to see if I can get the compressor clutch to engage?
Thanks for any suggestions.
Thanks for any suggestions.
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From: Sunshine Coast, Queensland, Australia
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Jumping wiring to kick a compressor when the system is low is a great way to cause more damage.
perhaps test for voltage to low pressure switch when switching AC on first. If voltage is present then test for voltage to compressor clutch.
I had my switch fail. Thus no voltage to the low pressure switch.
Proper trouble shooting will solve the problem without causing more damage.
perhaps test for voltage to low pressure switch when switching AC on first. If voltage is present then test for voltage to compressor clutch.
I had my switch fail. Thus no voltage to the low pressure switch.
Proper trouble shooting will solve the problem without causing more damage.
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Joined: Oct 2023
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From: Greeley, CO
Jumping wiring to kick a compressor when the system is low is a great way to cause more damage.
perhaps test for voltage to low pressure switch when switching AC on first. If voltage is present then test for voltage to compressor clutch.
I had my switch fail. Thus no voltage to the low pressure switch.
Proper trouble shooting will solve the problem without causing more damage.
perhaps test for voltage to low pressure switch when switching AC on first. If voltage is present then test for voltage to compressor clutch.
I had my switch fail. Thus no voltage to the low pressure switch.
Proper trouble shooting will solve the problem without causing more damage.
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OK, but there is a reason the low pressure switch shuts the power off to the compressor clutch. Running the system empty generally isn't a good idea. No matter how many times you may have gotten away with it.
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From: Greeley, CO
I agree running it empty is not a good idea, and yes a low refrigerant charge will keep the switch open and not engage the compressor. But he specifically asked for a way to bypass the system to engage the compressor, and this is one way. I didn't suggest he permanently close the switch and run the compressor full time.
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Yes, and clearly just putting 12V to the compressor clutch wire with a properly grounded compressor will engage the clutch. And clearly anyone with any experience would know that. And know not to run the system empty.
The real unknown here is the experience of the OP. A novice might try hot wiring the compressor and going for a drive.
The real unknown here is the experience of the OP. A novice might try hot wiring the compressor and going for a drive.
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Joined: Jan 2015
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From: Surf City USA
Thanks guys for your input... much appreciated!
I only want to see if I can engage the compressor clutch enough to see if it could be my switch that is bad.
I am a novice at testing electrical systems such as this... so low pressure side / high pressure side doesn't mean anything to me. I may have to take it to a shop to be tested.
I only want to see if I can engage the compressor clutch enough to see if it could be my switch that is bad.
I am a novice at testing electrical systems such as this... so low pressure side / high pressure side doesn't mean anything to me. I may have to take it to a shop to be tested.
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Yes John it could be your switch is bad. There is a plastic rivet that holds it together that can fail. The real issue here is, there is plenty of "Stuff" between that main switch and the compressor clutch. Like the low pressure switch that is mentioned above. So. Just hot wiring the compressor isn't really a great answer to anything. Proper testing is generally a better idea. Better than just guessing and throwing parts at it.
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St. Jude Donor '22
hmm.
all said and done, research the operation of the A/C sytem so you will understand,
low side
high side
pressure switch.
basically, if there is no gas, pressue, then clutch should not work.
all said and done, research the operation of the A/C sytem so you will understand,
low side
high side
pressure switch.
basically, if there is no gas, pressue, then clutch should not work.