How much 134a?

Slant6Demon said

Thanks all. Finally got warm enough to work with AC. These are the numbers at 75 deg ambient, 50% humidity, doors open, fan blowing on condenser, 1600 rpm. 15 psi low, 165 high, 45 deg at vent. Am I under charged? I only put in about 19 oz 134a. The low side seems low, but the vent temp seems ok. How much under charge will harm a Sanden compressor? Thanks.

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My new Classic Auto Air unit takes 24 oz they say.
They also say if the compressor is noisy it’s over filled.
That kinda infers that one can fill until it gets noisy and let a little out.

FYI, I had 40 degree air with the 24oz, but only showed about 20 on the low side and 150 on the high side.
I then added a little more coolant until the low side was
Around 30 lbs and it got noticeably cooler, but the compressor was still quiet.