Lochinvar & A.O. Smith 100208552 Temp Sensor

The Lochinvar & A.O. Smith 100208552 Water Temperature Sensor is a critical NTC thermistor designed for high-accuracy thermal monitoring in commercial and residential hydronic systems. This OEM replacement part, also identified by cross-reference numbers TST2032, TST2032K, and 100274731, provides the precise resistance-to-temperature feedback required by the system's control board to manage firing rates and maintain setpoint stability. Featuring an 11.75-inch lead, the sensor ensures a secure connection for deep-well insertion, effectively preventing the erratic heating cycles or high-limit trips often caused by generic, out-of-calibration alternatives.

This boiler temperature sensor is compatible with a wide range of high-efficiency equipment, including Lochinvar Knight (WH, WB) and Armor (AW) series, as well as A.O. Smith industrial water heaters. Built to withstand demanding boiler room environments, the 100208552 sensor operates across a wide thermal range to provide real-time data, ensuring your equipment stays within safe operating parameters and maintains optimal peak efficiency.

Key Benefits for Technicians:

• Direct OEM Compatibility: drop-in replacement for Lochinvar TST2032 and TST2032K kits.
• Precise NTC Calibration: Delivers accurate resistance readings to prevent 100208552-related sensor failure codes.
• Extended 11.75" Lead: Simplifies routing to the control board in tight cabinet configurations.
• Wide Application Range: Validated for use in Lochinvar Knight, Armor, and A.O. Smith commercial systems.
• Enhanced System Reliability: Rectifies issues with inconsistent water temperatures and frequent safety shutdowns.

Common Questions:

Is the 100208552 interchangeable with the TST2032?
Yes, the 100208552 is the current manufacturer part number and is identical in technical specification to the TST2032 and TST2032K thermistor kits.

What are the symptoms of a failing water temperature sensor?
Common signs include erratic temperature displays on the control interface, "Sensor Failure" error codes (often 5 blinks on specific units), and the system failing to trigger the heating cycle despite being below the setpoint.

Does this sensor include the brass well?
This part number typically refers to the thermistor and lead assembly. It is designed to slide into the existing dry well or immersion bulb socket already installed in the heat exchanger or tank.

Disclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.