water heater maintenance

streamlining routine service calls

and fan control centers

This 117U1021 relay replaced 117U1001 and functions as a current-operated switch to manage the start winding circuit during the initial torque phase

Modine 5H0730570003 Block Vent Switch water heater maintenanceThe Modine 5H0730570003 Blocked Vent Switch is a critical safety component engineered to monitor flue gas temperatures and prevent hazardous operating conditions. This genuine OEM replacement part is specifically designed for Modine PD400 and BD400 unit heaters, serving as the direct functional successor to the legacy 5H73057 3 model. Operating as a manual reset safety switch, it is calibrated to trip when vent temperatures reach 200F (93C),