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    HVAC Systems · Air Conditioning Components

    High/Low Pressure Switch

    A refrigerant-side safety switch that opens the control circuit when system pressure climbs too high or drops too low, shutting down the compressor to protect it from damage caused by overcharge, blocked airflow, or refrigerant loss.

    Common uses

    Compressor protection, refrigerant-charge safety, lockout on abnormal pressures

    Common symptoms

    • Compressor will not start
    • Intermittent cooling
    • Lockout after short run

    Common repairs

    • Switch replacement
    • Charge verification
    • Airflow restriction cleanup

    Related terms

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