A/C Compressor Question
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A/C Compressor Question
I just recharged my A/C. The PO did the 134 retrofit kit, and there are no major leaks that I can find. The system seemed to be completely empty, so I put in 36oz. The fill gauge was reading around 40-45 (not sure what the unit of measurement was) and was in the "green zone" on the gauge.
My compressor kicks on at idle, and will stay on for 45+ seconds at a time before cycling off, which is normal behavior to my knowledge.
However, when I drive the car, at any RPM above say 1500, the compressor cycles at a 3-5 second rate... 3-5 seconds on 3-5 seconds off... Is this normal behavior in these cars? Is this indicative that it needs more refrigerant, or less refrigerant?
My carburetor needs a rebuild, which is leaving me kinda low on power to begin with, and the constant power drop off / surging from the compressor cycling is quite annoying on the highway.
Any tips or advice is appreciated
My compressor kicks on at idle, and will stay on for 45+ seconds at a time before cycling off, which is normal behavior to my knowledge.
However, when I drive the car, at any RPM above say 1500, the compressor cycles at a 3-5 second rate... 3-5 seconds on 3-5 seconds off... Is this normal behavior in these cars? Is this indicative that it needs more refrigerant, or less refrigerant?
My carburetor needs a rebuild, which is leaving me kinda low on power to begin with, and the constant power drop off / surging from the compressor cycling is quite annoying on the highway.
Any tips or advice is appreciated
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Re: A/C Compressor Question
When checking compressor cycling, it should be done at a high idle but I'm not sure the best way to test that with a gas engine. Normally, the compressor should cycle on for a minimum of 7 seconds. Any less and it's probably low on freon. Can't make a good guess without seeing pressure gauge readings.
If you had no freon in the system and charged it up, there's a good chance that there's now air in the system. Air is a non noncondensable and screws up the efficiency of the AC system.
Ways of checking for leaks is with a freon sniffer or charging the system with nitrogen and spraying everything with a soapy water solution to look for bubbles. If your system leaks, your charge will soon disappear and you'll have no AC again.
If you had no freon in the system and charged it up, there's a good chance that there's now air in the system. Air is a non noncondensable and screws up the efficiency of the AC system.
Ways of checking for leaks is with a freon sniffer or charging the system with nitrogen and spraying everything with a soapy water solution to look for bubbles. If your system leaks, your charge will soon disappear and you'll have no AC again.
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Re: A/C Compressor Question
When I started, the compressor wouldn't cycle at all, but after about 10 seconds of adding the 134, it kicked in.
There was good vacuum on the low side before I started to fill it, I can't remember the reading I got on the gauge, but seeing there was a vacuum, I figured there wasn't any air in the system.
I guess then my main question is how much 134 these cars normally hold. If it's quick cycling could mean it's low on refrigerant, I can always get a little more if I know how much more to add.
Besides the quick cycling (and resultant feel of loss of power due to under-performing carburetor), the A/C is performing wonderfully, I'm getting Ice cold air out of the vents at all speeds...
There was good vacuum on the low side before I started to fill it, I can't remember the reading I got on the gauge, but seeing there was a vacuum, I figured there wasn't any air in the system.
I guess then my main question is how much 134 these cars normally hold. If it's quick cycling could mean it's low on refrigerant, I can always get a little more if I know how much more to add.
Besides the quick cycling (and resultant feel of loss of power due to under-performing carburetor), the A/C is performing wonderfully, I'm getting Ice cold air out of the vents at all speeds...
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