Recently replaced the air compressor and dryer, evacuated and recharged the system to around 37 psi. It doesn't leak, and when the compressor is forced, cold air will blow. Because the compressor can be forced to engage with the paper clip trick, does that mean it's not an electrical issue? I've also heard other issues that may cause the compressor to not engage include a bad thermostat or bad expansion valve. So, what's your opinion on the next logical step to make?

 

There are low and high pressure shut off switches. You don't fill a/c systems by pressure either, you fill them by volume. There will be a sticker on the core support saying how much refrigerant it needs.

 

The volume is correct. Any other suggestions?

 

I should have said weight, not volume, but you get the point. You really need a set of manifold gauges to see what's going on. I suppose it's possible that you could have a bad pressure switch or temperature probe in the expansion valve.