the module is likely the culprit

protecting the system from dangerous exhaust build-up or blocked vent conditions

allowing for efficient on-site mechanical service

the 700-442 provides a versatile solution for standing pilot heating equipment requiring consistent manifold pressure and high-volume flow

Rated at 80+10 MFD with a 370V tolerance

Dwyer Instruments DXW-11-153-2 Pressure Switch 30067439-890 the module is likely theThe Dwyer Instruments DXW 11 153 2 is a professional grade wet wet differential pressure switch engineered for contractors who require precision in demanding HVACR and industrial applications. This Series DX differential pressure switch utilizes opposing diaphragms and a pivot mechanism to sense the pressure delta between two sources, providing a reliable SPDT snap switch output for critical control logic. With an adjustable range of 10 to 25 psi,