HVAC: How To Wire High And Low Pressure Switch For A AC (How To Install High/Low Pressure Controls) High And Low Pressure Switch Wiring Diagram / HVAC Low Pressure Switch / HVAC High Pressure Switch

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In a air conditioning/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. This is necessary to prevent the possible damage of equipment.

When the pressure in discharge line raise above a certain limit of pressure, high-pressure control device operates and stops the compressor by cutting the power supply given to the motor input.

Low-pressure controls can protect compressors from too low of a pressure situation in case of a coil freeze-up or lost refrigerant charge. Low-pressure controls can also protect some water chillers from freeze-ups.