100 psi on low end and compressor clutch not engaging

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Joined: Sun Apr 09, 2017 7:27 pm

100 psi on low end and compressor clutch not engaging

Postby Texastravis » Sun Apr 09, 2017 7:40 pm

Compressor went out on my 07 Chevy silverado. I installed a new compressor, new accumulator, and new orifice tube. Ran a vacum for awhile then shut off to check for leaks, good to go. First 12 oz can of 134a sucked right in. The second can however only got about half in before it stopped sucking.

Watching my gauges closely it looks like the ac clutch is not kicking on until it gets to about 100-110 psi and then cuts off at 90 psi. It is making it virtually impossible to put in more refrigerant.... but I probably dont want to keep putting in refrigerant if my ac clitch isnt kicking on until that high of pressure?

Any ideas? I thought it was my new low pressure switch that I installed on the new accumulator but I uninstalled it and reinstalled the old switch by nothing.
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Joined: Sat Apr 15, 2017 3:00 am

Re: 100 psi on low end and compressor clutch not engaging

Postby DarrylS » Sat Apr 15, 2017 3:59 am

If should be a simple 2 wire plug on the low pressure switch? If so just use a piece of wire to jumper it to keep the compressor running while charging. I am not clear on if your 90 100 psi pressure was on low or high side? (must be the high side?) if you are reading the low side (blue gauge) the low pressure switch will usually disengage the compressor clutch at around 20 to 25 psi. So you have to force it to stay on while charging cuz the low side can drop real low when first adding refrigerant until it gets closer to being full.

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