What is the purpose of the low pressure control?
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 are the functions of the high-pressure control?
High-pressure controls can protect compressors and system components from dangerously high-pressure situations by shutting the compressor off at certain elevated pressures. Some high- and low-pressure controls have to be manually reset and some reset automatically.
What is a dual pressure switch used to control?
PS2 Dual Pressure Controls are designed for use on high and low pressure applications in refrigeration, air conditioning, and heat pump systems. This control react to changes in either low or high side pressures, providing single-device control of the compressor or other electrical device.
What is the job of a high-pressure cut out?
In refrigeration system the high-pressure cut-off switch is a control device which is used as safety control. The compressor is stopped by cutting the power supply of the motor of the compressor whenever the discharge pressure of the compressor becomes excessive.
What causes low pressure lockout?
A low pressure alarm indicates the controller has received an open signal from the normally closed low pressure switch circuit. Three active alarms within one hour will trigger a compressor lockout to protect the refrigerant circuit. The lockout can be cleared by power cycling the controller.
What does a Txv valve do?
A thermostatic expansion valve (TXV) (see Figure 1) is a refrigeration and air conditioning throttling device that controls the amount of refrigerant liquid injected into a system’s evaporator—based on the evaporator outlet temperature and pressure—called the superheat.
What is cut-in and cut out pressure?
Cut-in and cut-out pressure These are simply the two pressures at which the compressor starts and stops. The compressor will stop when it reaches the cut-out pressure and will start again when the pressure drops back to the cut-in pressure.
Why does my furnace have 2 pressure switches?
Two Stage: If you have a two stage furnace, it is likely that you will have two pressure switches. This is because your furnace has two heat exchangers, requiring each exchanger to have its own switch. Draft pressure switches tend to operate at 24 volts.
Which pressure control can be used as a temperature control?
The temperature of a refrigerated box can be controlled by a low-pressure control (LPC), instead of a thermostat, because of the pressure/temperature relationship in the refrigeration system.