On some switches it says on off but the words auto off would be more correct.
High pressure cutout switch operation.
Things that can cause the high pressure switch to trip include.
When the pressure in discharge line raise above a certain limit of.
When the pressure is too low the compressor risks damage due to running with low oil.
Ac not blowing cold in this video we will explain what the a c pressure switch is for and how a bad faulty ac pressure switch m.
In refrigeration system the high pressure cut off switch is a control device which is used as safety control.
So really you can look at the ac pressure switch as working in the same way as a fuse in an electrical circuit.
It monitors the pressure of the refrigerant on its respective side of the system.
The spring is highly compressed now.
The high pressure cutout switch on the other hand is a safety device only and does not have control of compressor operation under normal conditions.
When the high pressure gas enters the bellow the bellow expands and presses the spring.
Condenser coils plugged up with dirt and debris.
Bad condenser fan motor.
What ac pressure switch does.
Moisture air mixed refrigerants.
The compressor is stopped by cutting the power supply of the motor of the compressor whenever the discharge pressure of the compressor becomes excessive.
The high pressure cut out as shown in the diagram is of a simple construction.
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.
If the incorrect pressure is sensed the switch will open the a c compressor clutch circuit to prevent operation.
Once the necessary repairs are made to bring the pressure into specification the switch will allow normal clutch.
Of course an over charge of refrigerant can cause the high pressure switch to open this is especially true with microchannel coils.
If there is no fluid in the system then it s going to grind to a halt again.
Operation of a high pressure cut out.
It has a bellows that is set against a spring.
Non condensables in the system can cause high head pressure.
A heavy load in the occupied space adds more super heat to the coil and can cause high pressure readings.
If the pressure is too high it could burst the compressor causing a leak of refrigerant fluid.
The nut at the end of the spring is used to adjust the cut out pressure.
Some pressure switches have a switch or push button for on off control.
This is necessary to prevent the possible damage of equipment.
Oil failure switch an oil failure switch is provided with high speed compressors.
The clutch cycling switch measures a c pressure near the evaporator outlet and is often mounted on the accumulator.
