Given the technical nature of these components

featuring a high-precision air adjustment dial and air shutter assembly that allows for granular calibration of the combustion air intake

Does the impeller work in low-flow conditions

Cross-reference your furnace model number or original part stamping

Siemens Combustion QRA75.A17 Detector 322838-753 Given the technical nature ofThe Siemens Combustion QRA75. A17 is a high precision, self checking UV detector engineered specifically for continuous duty industrial burner applications. Designed for the supervision of gas and oil flames, this ultraviolet flame detector utilizes a high sensitivity UV cell to monitor combustion and ignition spark proving with professional grade reliability. Operating at AC 120 V, the QRA75. A17 features a 69mm detector tube and a built in stepper