These readings will vary depending on the type of system, weather conditions and the amount of refrigerant charge.An example of healthy readings would be 30 to 40 PSI on the low side and 200 to 225 PSI on the high side.
Many car mechanics say the air-conditioning compressor is the most important part of the system. However, in order for the AC to function properly, it relies on each individual part to operate as per design intent.
As an example, if all of the components are functioning properly, yet the AC expansion valve is stuck closed the system will not blow cold air from the dash vents.
With that said, the high pressure supplied from the compressor outlet is just as important.
Keeping an old air-conditioning system on a classic car operating correctly is challenging to say the least.
Although these older systems have a few safety features in place to help prevent damage to the AC compressor, this damage can still occur.
Unfortunately, a lot of problems that professional mechanics see are self-inflicted by the owner.
Here we'll review how a compressor works and how to test for proper operation.
They engage the belt driven compressor by running current through an electromagnet mounted in between the compressor drive shaft and the pulley.
This locks the engine revolution to the input shaft and operates the pistons inside. The low pressure line they call the inlet or suction side.