What is the purpose of a low and high pressure switch in an AC system?
What is the purpose of a low and high pressure switch in an AC system?
A high pressure switch (HPS) and a low pressure switch (LPS) are protective devices for the compressor and refrigeration circuit. The high pressure switch monitors the system for an inoperative outdoor motor, and/or a dirty/restricted condenser (outdoor) coil.
What should the low side of the air conditioner pressure be?
The low side pressure in your air conditioning system should drop down significantly when your engine is running and your AC compressor is cycling on. When the compressor shuts off or you turn your car off the pressures in the system will equalize between the high and low side so the low side pressure will read much higher.
Where are the low and high AC pressure switches located?
The low-pressure side switch is found before the AC compressor, while the high-pressure switch comes after the compressor. Most AC pressure switches are found within the engine compartment, but some manufacturers put them elsewhere. A look in your service manual will show you the appropriate location for your model. AC Pressure Switch Function
How can I tell if my AC is low or high?
To gauge the pressure, hook up a gauge set to the AC system and record the pressures of both low and high sides. Check the ambient temperature and see if the pressures match the numbers on the pressure chart. Compare the pressure readings with the pressure chart.
How does a high pressure AC system work?
To measure the pressure in the high-pressure side of your system, you need a little fancier piece of equipment. The pressures in the high-pressure side of your system are so high that it requires special hoses and connections along with a special gauge to contain the pressure and ensure you don’t release any of the refrigerant to the atmosphere.
The low side pressure in your air conditioning system should drop down significantly when your engine is running and your AC compressor is cycling on. When the compressor shuts off or you turn your car off the pressures in the system will equalize between the high and low side so the low side pressure will read much higher.
What should the PSI be on an A / C system?
An A/C System that is working properly should have 150 PSI on the high side and 30 PSI on the low side.
The low-pressure side switch is found before the AC compressor, while the high-pressure switch comes after the compressor. Most AC pressure switches are found within the engine compartment, but some manufacturers put them elsewhere. A look in your service manual will show you the appropriate location for your model. AC Pressure Switch Function
To gauge the pressure, hook up a gauge set to the AC system and record the pressures of both low and high sides. Check the ambient temperature and see if the pressures match the numbers on the pressure chart. Compare the pressure readings with the pressure chart.
