Clutch Cycling Switch
In a (CCOT) cycling clutch orifice tube system, there's a constant pressure drop across the fixed orifice tube. It doesn't vary or change its output according to demands like an expansion valve does. A clutch cycling switch is used to activate and deactivate the compressor clutch instead. When the switch is stuck closed, the compressor clutch remains engaged and does not cycle. If it's stuck open, the compressor clutch does not engage, and there is no compressor operation.
Accumulators are on the low side of the system between the evaporator and the compressor. The clutch cycling switch cycles the compressor according to the pressure in the accumulator. This system uses a clutch cycling switch to activate and deactivate the compressor clutch according to system pressure.
The switch senses system pressure and rapidly cycles the compressor on and off when the refrigerant is low. The same is true for a CCOT system that uses a thermostat to measure the evaporator's fin temperature to cycle the clutch. When the cycling clutch switch is operating correctly, this action should maintain the evaporator core at a cold, but not freezing 35° to 45° F.