Non condensables in the system can cause high head pressure.
High pressure cutout switch operation.
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 in discharge line raise above a certain limit of.
In the auto on position the pressure switch works as expected.
If the pressure is too high it could burst the compressor causing a leak of refrigerant fluid.
Of course an over charge of refrigerant can cause the high pressure switch to open this is especially true with microchannel coils.
A heavy load in the occupied space adds more super heat to the coil and can cause high pressure readings.
Once the necessary repairs are made to bring the pressure into specification the switch will allow normal clutch.
The spring is highly compressed now.
A simple push of the switch will reset the switch and the operation of the air conditioner should return to normal until the pressure exceeds the rating of the switch.
So really you can look at the ac pressure switch as working in the same way as a fuse in an electrical circuit.
What ac pressure switch does.
The pressure switch is set at an high pressure.
Bad condenser fan motor.
The high pressure cut out as shown in the diagram is of a simple construction.
The compressor is stopped by cutting the power supply of the motor of the compressor whenever the discharge pressure of the compressor becomes excessive.
This is necessary to prevent the possible damage of equipment.
When the high pressure gas enters the bellow the bellow expands and presses the spring.
The nut at the end of the spring is used to adjust the cut out pressure.
In refrigeration system the high pressure cut off switch is a control device which is used as safety control.
If the incorrect pressure is sensed the switch will open the a c compressor clutch circuit to prevent operation.
Some pressure switches have a switch or push button for on off control.
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 pressure is too low the compressor risks damage due to running with low oil.
On some switches it says on off but the words auto off would be more correct.
Moisture air mixed refrigerants.
Things that can cause the high pressure switch to trip include.
Oil failure switch an oil failure switch is provided with high speed compressors.
It has a bellows that is set against a spring.
Operation of a high pressure cut out.
It monitors the pressure of the refrigerant on its respective side of the system.
If there is no fluid in the system then it s going to grind to a halt again.