Lennox 17F19 Collector Box 323269-701 The blower door safety switch

The blower door safety switch is a furnace door interlock that prevents the system from running if the blower compartment door is not properly secured

For technicians troubleshooting a 3-flash error code or a unit that fails to fire despite the blower running

Its robust design minimizes motor load during startup

For any service technician or mechanical contractor

the diaphragm or internal contacts are likely defective

Lennox 17F19 Collector Box 323269-701 The blower door safety switchThe Lennox 17F19 Collector Box, also identified as the 619598 20 cold end header box kit, is a critical recovery component for high efficiency condensing furnaces. Designed specifically for the Lennox ML195 series and select 90% AFUE residential units, this OEM furnace replacement part manages the collection and redirection of corrosive condensate from the secondary heat exchanger. Precision engineered to prevent fluid backup into the combustion air