Lochinvar & A.O. Smith TST2900 Temperature Controller

The Lochinvar & A.O. Smith TST2900 Temperature Controller (cross-referenced as part number 100170632) is a critical OEM immersion thermostat designed for high-recovery commercial water heating applications. This direct-acting temperature control provides precise thermal regulation for Lochinvar Copper-Fin and A.O. Smith Conservationist series units. Engineered with a rugged sensing bulb and capillary assembly, the TST2900 ensures accurate setpoint maintenance and fast response times to thermal load changes. Contractors utilize this replacement water heater controller to restore factory-spec cycles and prevent overheating in potable water systems. Its integration with existing commercial boiler controls is seamless, offering a 120V/240V compatible electrical interface. For technicians servicing high-efficiency water heaters, verifying this aquastat controller against the 100170632 interchange ensures long-term system stability and eliminates calibration drift often found in generic aftermarket equivalents. This is a vital component for maintaining the operational baseline of heavy-duty hydronic and hot water supply equipment.

Key Benefits

• Broad Compatibility: Direct OEM replacement for both Lochinvar TST2900 and A.O. Smith 100170632 part numbers.
• Precision Thermal Sensing: Designed for high-recovery systems where accurate temperature differentials are required for safety and efficiency.
• Durable Construction: Features a heavy-duty housing and thermal well interface to withstand commercial water heating environments.
• Field-Proven Reliability: Reduces call-backs by maintaining consistent setpoints in multi-boiler configurations.

Common Questions

Is the 100170632 identical to the TST2900?
Yes, these part numbers are interchangeable. The 100170632 is the updated SKU used across the A.O. Smith and Lochinvar parts network for the original TST2900 controller.

What systems use this temperature controller?
It is primarily found in high-recovery commercial water heaters, large-volume storage tanks, and specific series of Lochinvar Copper-Fin boilers.

Can this be used as a high-limit safety cut-out?
The TST2900 is engineered as an operating control; it should be used in conjunction with a dedicated manual-reset high-limit switch per local mechanical codes.

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.