Lochinvar & A.O. Smith 100170488 Lower Sensor

The Lochinvar & A.O. Smith 100170488 Lower Sensor is a critical thermistor-based component engineered for precise thermal monitoring in high-efficiency water heating systems. As an exact replacement for the TST1188 sensor, this part ensures the control board receives accurate resistance feedback from the lower portion of the tank. For technicians troubleshooting Lochinvar water heater error codes or A.O. Smith temperature sensor faults, installing this OEM-spec lower tank sensor is essential to restore the correct firing sequence and prevent short-cycling. The 100170488 temperature probe is designed for seamless integration with a wide range of commercial and residential models, maintaining the HVAC system reliability expected by contractors. By accurately tracking lower-zone temperatures, it plays a vital role in optimizing the BTU input and protecting the heat exchanger from thermal stress.

• Precision Thermal Monitoring: Provides real-time data to the control module to ensure accurate set-point maintenance.
• Direct OEM Interchange: Fully compatible with systems requiring the TST1188, ensuring a drop-in fit without field modifications.
• System Protection: Helps prevent overheating and diagnostic lockout conditions by monitoring stratification levels.
• Rugged Construction: Built with high-grade thermistor materials to withstand the corrosive environment of a pressurized water tank.

• What are the symptoms of a failing 100170488 sensor? Common signs include irregular water temperatures, frequent error codes related to sensor "open" or "shorted" circuits, and the system failing to initiate the heating cycle.
• Is the 100170488 interchangeable with the TST1188? Yes, the 100170488 is technically identical to the TST1188 and is the standard replacement part for Lochinvar and A.O. Smith applications.
• How do I verify if the sensor is bad? Use a multimeter to check the resistance (Ohms) against the manufacturer’s temperature-resistance chart; a reading outside the specified range usually indicates a hardware failure.

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.