Lochinvar & A.O. Smith 100170487 Upper Sensor 321042-401 Standardized Fit: The 1/4-20" threaded

Standardized Fit: The 1/4-20" threaded shaft and 22-inch leads allow for direct replacement in HVAC fan motor assemblies

Models include 5-1/2” sensing element

you should verify your specific model number (e

Easy Installation: Standard 2-wire lead terminals and mounting brackets allow for a fast swap during service calls

It is not a universal part and should only be used where the 383-500-630 part number is specified in the manual

Lochinvar & A.O. Smith 100170487 Upper Sensor 321042-401 Standardized Fit: The 1/4-20" threadedThe Lochinvar & A. O. Smith 100170487 Upper Sensor (formerly TST1187) is a critical thermistor based component engineered for high precision temperature monitoring in residential and commercial water heaters. As a direct immersion NTC temperature sensor, it provides real time resistance feedback to the control board, ensuring the appliance maintains optimal setpoints while preventing dangerous high limit conditions. This OEM water heater sensor is