kd4gij

How can you check refrigerant level with out the compressor running?

white89gt

Exactly.... you can't.

Lerrooy

It was at 70 psi.

The kit I bought to refill the refrigerant said to fill to 30 psi.
After that you use the chart to get it to where you need it with the a.c. on.

I figure that should be high enough pressure on the low side?

white89gt

You can not properly check the A/C without the compressor running. Too many variables at play otherwise.

white89gt

And as far as "high enough", that is too high. But once again, it can't be checked properly without it running.

paker

At 70 deg F, R134a has 70 psi. I think 70 psi will make AC compressor run long enough to check AC clutch operation. If AC clutch didn't engage at all, it is faulty.

white89gt

Did you try and bypass the low switch? Just take the connector off and put a jumper wire across the harness. I've used this method several times to charge systems.

paker

If OP wants to know if AC clutch engages (even for a few seconds), he doesn't have to bypass AC low pressure switch. AC clutch, if working properly, will engage for a few seconds until pressure drops to about 25 psi.

white89gt

Not if the switch doesn't work.

paker

Now I get it, White89. Thank you for the explanation.