Lochinvar & A.O. Smith 100274734 Flue Sensor 323613-751 The internal switches are rated

The internal switches are rated for 2 HP at 120V AC

Flashing LEDs on the left side of the 3-digit display indicate an active alarm condition

8-foot power and control cables eliminate the need for separate terminal block assembly

or when 24 VAC is confirmed at the terminals but no gas flow is detected at the burner

ensuring the flame is correctly directed into the heat exchanger

Lochinvar & A.O. Smith 100274734 Flue Sensor 323613-751 The internal switches are ratedThe Lochinvar & A. O. Smith 100274734 Flue Sensor is a critical safety component designed for high efficiency condensing boilers and water heaters. This exhaust temperature sensor monitors the heat levels within the venting system to prevent heat exchanger damage and plastic vent meltdown. Also identified by part number TST2013, this NTC thermistor provides the control board with precise resistance readings, ensuring the unit modulates or shuts down