OEM Lennox Pressure Switch — 57W83

The genuine OEM Lennox 57W83 pressure switch is a combustion safety control that verifies proper venting and airflow before your furnace is allowed to ignite. It reads the negative pressure generated by the draft inducer and closes its contacts to tell the control board the flue is clear and the system is safe to fire. Manufactured to Lennox specifications, the 57W83 arrives with the precise set point your furnace's ignition sequence depends on.

Common failure symptoms: When this switch degrades or its calibration drifts, the furnace may fail to light, ignite and immediately shut off, short cycle, or display a pressure switch fault code. Obstructed vents, disconnected or cracked sensing hoses, condensate in the port, or a tired diaphragm commonly prevent the contacts from closing.

Why OEM matters: The 57W83 is calibrated to a specific pressure threshold tied to your Lennox unit's inducer and heat exchanger. Using the genuine part ensures the safety circuit trips exactly when it should, avoiding nuisance lockouts from mismatched aftermarket switches while safeguarding against unsafe draft conditions. The OEM component guarantees correct fit, reliable ignition, and continued warranty protection for your Lennox furnace.