Lochinvar & A.O. Smith 100278114 Sensor 321702-401 Technician-Friendly Design: Integrated 1/8-27 NPT

Technician-Friendly Design: Integrated 1/8-27 NPT pilot tap simplifies troubleshooting and pressure checks

If the main ignition module has power but the status light board remains unresponsive

this is a line voltage thermostat designed specifically for direct switching of high-voltage electric heating equipment

Industrial Build Quality: Features a resilient 56YZ frame and TEAO enclosure for protection against moisture and debris in outdoor condenser units

Lochinvar & A.O. Smith 100278114 Sensor 321702-401 Technician-Friendly Design: Integrated 1/8-27 NPTAs a seasoned technician, you know that accurate temperature feedback is the backbone of any high efficiency condensing boiler or water heater. The Lochinvar & A. O. Smith 100278114 Sensor is a critical 10k Ohm NTC thermistor designed for precision Domestic Hot Water (DHW) monitoring. This genuine OEM replacement part ensures the control board receives real time resistance data to modulate firing rates and maintain setpoint stability. Whether you are