AC Compressor Cycling

Cheetokps

Cheetokps

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Wallingford, CT
My ac is blowing very warm (around 75 degrees) and I noticed my compressor is cycling on and off. I bought a set of manifold gauges to measure the level, does this look like it’s low on refrigerant? I’m not sure how to tell because it keeps going up and down when the compressor kicks on. When the compressor turns on it drops to about 20psi before turning off again, which makes me think it is low



 
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Add some refrigerant. Be sure that you shut off the gauge or quickly disconnect your refrigerant supply if/when the compressor cycles, otherwise you will be backfilling the refrigerant out of your TJ and into the supply.
 
The low pressure switch is on top of the accumulator as seen here. Disconnect the wire connector and connect the two terminals however you can.

I would suspect your refrigerant is low from the video.

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glowell222 said:
Add some refrigerant. Be sure that you shut off the gauge or quickly disconnect your refrigerant supply if/when the compressor cycles, otherwise you will be backfilling the refrigerant out of your TJ and into the supply.
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This is not a typical procedure that I have seen or heard of anyone doing.

Once you start adding refrigerant, the compressor will gradually have longer and longer cycles until it senses enough refrigerant to stay on full time. Keeping dumping it in there until the compressor quits cycling but keep an eye out on the pressure gauge to make sure you don't over-charge

90F ambient temp, the low pressure side should be between 38-47 psi. High side should be 250-300 psi
 
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Typically, the pressure on the system when it is disengaged is much higher than the pressure on a can of 134a. If there is no backfill preventer in the can, the higher pressure on the system will over ride the lower pressure on the can. Also, don't "dump" the refrigerant. The low pressure side is a vapor line, and putting liquid into the compressor on the vapor line is a very bad idea.
 
glowell222 said:
Typically, the pressure on the system when it is disengaged is much higher than the pressure on a can of 134a. If there is no backfill preventer in the can, the higher pressure on the system will over ride the lower pressure on the can. Also, don't "dump" the refrigerant. The low pressure side is a vapor line, and putting liquid into the compressor on the vapor line is a very bad idea.
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I've never known anyone to have an issue. The low pressure side is also the "fill" side
 
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My point is: if you have a can or bottle of liquid refrigerant, don't dump liquid into the low (vapor "fill") side. Keep the bottle upright and feed in only vapor. Trying to compress a liquid will damage the compressor.
 
glowell222 said:
My point is: if you have a can or bottle of liquid refrigerant, don't dump liquid into the low (vapor "fill") side. Keep the bottle upright and feed in only vapor. Trying to compress a liquid will damage the compressor.
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The way i saw online is keep it upright and turn it to 3 o clock every now and then while shaking lightly, is that the right way?
 
Rob L. said:
that could be cumbersome trying to do that a read a gauge unless you have a buddy. And you might want something insulated to hold onto. it would be best if you haver some alligator clips.
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I got alligator clips hooked on, this is supposed to make the compressor stay on right? It isn’t turning on at all now
 
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Tilting the can is adding liquid. The better approach is to keep a bowl of hot water (from the tap) to help keep up the pressure on the can-just put the lower part of the can in the water for about a half-minute or so and that should boil off any refrigerant that has condensed in the can. Repeat as necessary.
 
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