What does a low pressure switch do?
The low pressure switch monitors the refrigeration system for a loss of refrigerant charge, and may also be helpful in stopping the evaporator (indoor) coil from freezing up due to a dirty filter or low airflow over the coil.
What would be the low pressure cut out for a low pressure switch used as a safety control?
The cut-in value of the low-pressure switch is generally set to a saturation pressure equivalent to the minimum expected ambient temperature. One manufacturer recommends a low-pressure switch setting of 15 psig cut in and 4 psig cut out, but that may not be an acceptable setting for all systems and all manufacturers.
How do you jump a low pressure switch on an air conditioner?
Unplug the plug on the low pressure switch. Use a stiff piece wire bent in a U shape to jump the plug (should be just two wires) stick your jumper wire in the plug. Even a paper clip will work. If your AC compressor kicks on, then you know the system is working.
Why do I need a low pressure switch?
That’s because the refrigerant carries the lubrication oil throughout the system. The low pressure switch cuts off compressor specifically to prevent compressor damage due to oil starvation. Low refrigerant charge = low or no oil circulation.
How to bypass 3 wire AC pressure switch easily?
You need to bypass 3 wire AC pressure switch through the B1 to B4. This is done to power the compressor clutch. When you do this, the connection will send 0-5 volts of pressure through the PCM fuse. However, in this step, you need to pay close attention to the numbers printed on the AC in mind.
Can a low pressure switch cause a compressor to go off?
Put the AC on MAX before checking the compressor. Before starting the next step of diagnosis, you should know that a low-pressure switch can create problems with the compressor clutch’s relay in some car models. The system’s computer keeps the relay grounded but it can go on and off due to the bad switch.
What does a high side pressure switch do?
There is a high side pressure switch, and low side pressure switch, and they both serve to monitor the system for pressure faults that can damage the compressor. When the pressure is too low, the compressor risks damage due to running with low oil.