McDonnell & Miller 354089 Switch Assembly 320788-702 this unit provides long-term field

this unit provides long-term field serviceability without necessitating a full valve replacement

offering a rugged snap-switch mechanism that handles industrial vibrations and thermal cycling

000 BTU Polaris models

Technicians frequently use this model as a direct replacement in systems requiring precise flame rectification

This valve utilizes a 3/8" inlet and a 1/2" outlet with ODF sweat connections for a standard 3-ton HVAC expansion valve setup

McDonnell & Miller 354089 Switch Assembly 320788-702 this unit provides long-term fieldThe McDonnell & Miller 354089 Switch Assembly, also designated as the Model SWA 150S M, is a critical replacement component engineered specifically for Series 150S and 157S low water cut offs and pump controllers. For technicians servicing steam boilers, this snap action switch assembly is the standard for maintaining precise liquid level control and ensuring high limit safety. Featuring a manual reset mechanism, this assembly requires professional