you will require the 4074EYK assembly instead

000 BTU/hr max capacity

ensuring the boiler or heater only fires when proper flow is established

It operates effectively as a 3-15 psi receiver gauge

Lochinvar & A.O. Smith 100170652 Sensor Kit 30067439-890 you will require the 4074EYKThe Lochinvar & A. O. Smith 100170652 Sensor Kit is a critical OEM replacement part engineered for precise flue gas temperature monitoring in Knight boiler systems and high efficiency water heaters. This flue temp sensor kit (cross referenced as TST3403) serves as a vital safety component, providing real time thermal reporting to the integrated control board. By continuously tracking exhaust discharge temperatures, the 100170652 flue sensor prevents