Lochinvar & A.O. Smith 100111317 Pressure Switch 319848-301 Look for a blown top

Look for a blown top membrane

It functions as a safety interlock

Built with high-temperature resistant housing to withstand typical plenum heat cycles

Standardized HVAC Voltage: Specifically designed for 24Vac circuits

Mechanical Reliability: Built to resist pilot tube clogging and slide-valve sticking

Lochinvar & A.O. Smith 100111317 Pressure Switch 319848-301 Look for a blown topThe Lochinvar & A. O. Smith 100111317 Pressure Switch is a critical OEM safety component engineered for precise airflow verification in high efficiency water heaters and boilers. This normally open air pressure switch is calibrated to a fixed set point of 0. 20" WC (Water Column), ensuring the combustion blower is generating sufficient negative pressure before the ignition sequence initiates. As a genuine 100111317 replacement part, it provides the