Common Questions What does "Normally Closed" mean for this specific blower relay

The Siemens Building Technology 243-0018 Signal Selector is a high-performance

verifying the continuity of this limit switch replacement is a standard diagnostic step

this component is the direct successor to the legacy B945672

You must always match the temperature ratings (L120-20) of the existing bimetal limit switch to ensure the furnace operates within its designed safety parameters

Reznor 201962 Limit Switch Common Questions What does "NormallyThe Reznor 201962 Limit Switch is a high temperature safety control engineered for precision in commercial HVAC unit heaters. This OEM Reznor 201962 component features a calibrated 170 250F temperature range and an auto reset function, ensuring the system resumes operation once internal temperatures return to a safe threshold. Designed for industrial gas fired heaters, it serves as an essential SPST limit control, specifically replacing worn or