What is the difference between CFR and VFR settings on this board

delivering a substantial steam discharge rate of 2

Fabricated with durable metal "tablock" construction

While originally configured for 3

opening only upon receiving a 24-volt signal from the thermostat or integrated control board

Lennox 10M66 Limit Switch 323269-701 What is the difference betweenThe Lennox 10M66 Limit Switch is a critical safety component engineered for precise thermal monitoring in high efficiency gas furnaces and air handlers. For technicians diagnosing a Lennox furnace limit switch opening prematurely or failing to reset, this SPST (Single Pole Single Throw) thermal sensor provides the exact calibration required for OEM compliance and system safety. Operating on a normally closed circuit, the 10M66 is designed to break the