AC blows cool instead of cold

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Re: AC blows cool instead of cold

Postby bohica2xo » Sat Jun 09, 2018 11:03 am

Sounds like you have several issues.

1) Clutch gap. Obviously the compressor was NOT turning the first time you tested. With 100k on the clock an excessive clutch gap is a given.
Adjust the gap.

2)Possible Blend door issues.
With a cold & sweating line in to the evaporator something is getting cold.

3) Possible charge level issues
If it is cycling on low pressure with a full load on the evaporator it is probably low on charge. But just adding some refrigerant is not the answer. You should recover & weigh the charge to determine if it actually needs more refrigerant.

Your full load test is skewed by adding box fans. Your results are odd, I am hoping you misstated the relationship between the two low side pressures & the compressor engagement. It should engage at 45 psi & disengage at 22 psi.

If it is cycling on a low charge the rate of cycling should increase at higher rpm.

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Re: AC blows cool instead of cold

Postby joeld » Sat Jun 09, 2018 4:30 pm

First off, yea, I fat fingered the on/off info for the compressor cycle. Should be just like you described! Bad thing is, I had it all wrote down correct but still typed it in wrong.

1. Clutch was replaced by a NAPA reman. several years ago. Car had approx 63000 on it then. I replaced it with compressor on the car, this has been the only repair on AC system. On the first test I am certain the clutch was engaged and compressor was turning.

2. Possible, have not checked that.

3. I agree 100% about the adding freon as a "possible" fix. If I even do this at all it will be in small amounts. A couple of ounces and re-check.

Should the inlet and outlet of the evap be close to the same temp?

Thanks for your help, any other ideas will be appreciated.


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