Description
The Reznor RZ203933 Pressure Switch 0.75″ WC is a control component used to monitor differential pressure in heating equipment and confirm proper draught conditions during operation. It responds to pressure changes by switching electrical contacts when airflow reaches the calibrated threshold helping regulate safe system sequencing and shutdown protection. In HVAC systems, it is mounted in furnaces and rooftop heating assemblies, where it verifies inducer fan performance and ensures adequate venting through the combustion pathway before ignition. It prevents operation under restricted airflow conditions, supporting stable combustion safe exhaust handling, and startup and shutdown cycles under conditions.
