Lochinvar & A.O. Smith 100208834 Temp Sensor

Optimize your hydronic system’s firing rate with the Lochinvar & A.O. Smith 100208834 Outdoor Temp Sensor. This high-precision thermistor-based sensor is a critical component for outdoor reset control, allowing your boiler to adjust its water temperature setpoint based on actual ambient conditions. By providing real-time data to the integrated HVAC control board, it prevents short-cycling and significantly improves fuel economy in residential and commercial applications. Also identified as TST2311 and TST2311K, this OEM replacement sensor is built with a weather-resistant housing to withstand harsh environments without drifting in accuracy. It is the direct boiler temperature sensor solution for Knight XL KB399-800 series models and compatible A.O. Smith water heaters. For any technician performing a system diagnostic or seasonal maintenance, replacing a fouled or unresponsive sensor ensures the outdoor reset curve remains calibrated, protecting the longevity of the heat exchanger and reducing operational overhead.

• Direct OEM Compatibility: Engineered specifically for Lochinvar Knight XL and A.O. Smith commercial units, ensuring seamless communication with the system controller.
• Precision Outdoor Reset: Facilitates accurate ambient temperature monitoring to automate the heating curve and maximize thermal efficiency.
• Durable Construction: Features a rugged, UV-resistant enclosure designed for outdoor air sensing in extreme weather conditions.
• Simplified Installation: Standard two-wire thermistor design allows for quick field replacement, effectively addressing sensor fault codes.

What are the signs of a failing 100208834 sensor?
Common indicators include the boiler failing to scale its firing rate, consistent outdoor sensor error codes on the display, or the system remaining in high-fire mode despite mild outdoor temperatures.

Is the TST2311 exactly the same as the 100208834?
Yes, 100208834 is the current part number for the legacy TST2311 and TST2311K models, offering identical resistance values and fitment.

Where should this sensor be mounted for the most accurate readings?
To avoid false readings from solar gain, mount the sensor on a North-facing wall, away from exhaust vents, windows, or direct sunlight.

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.