While both look similar

For technicians performing burner repair or preventative maintenance

It is a critical component for technicians performing a furnace gas valve replacement where exact voltage and pressure specifications are required to maintain system safety and performance standards

Is an EPA 608 certification required for purchase

Reliable 120V Operation: Designed for high-duty cycles to prevent premature failure during extreme cold-weather demands

Lochinvar & A.O. Smith 100111329 Relay Switch 328140-751 While both look similarThe Lochinvar & A. O. Smith 100111329 Relay Switch is a critical OEM 24 VAC control component engineered for high recovery commercial water heaters and hydronic boiler systems. This genuine relay replacement manages the sequential activation of heating elements and integrates seamlessly with the Smart System control panel to maintain precise water temperature setpoints. Designed for heavy duty cycling, the 100111329 relay facilitates power