The Siemens Combustion 7MF-421-030 Pressure Sensor is a precision pressure-sensing component designed to monitor and measure pressure levels in HVAC combustion and heating systems. It operates by detecting changes in pressure and converting them into an electrical signal for accurate system monitoring and control. This sensor is commonly used with gas furnaces, boilers, burners, and o... https://www.partshnc.com/7mf-421-030-siemens-combustion-pressurer-sensor-0-30-psi-4-20ma