For the M611 series

a 2-pole contactor can replace a 1-pole unit

As a critical draft inducer assembly component

Is the B1399501 bearing interchangeable with other brands

the Maxitrol MR212DH-1212 is the standard for high-capacity flow control in direct fired burners

Lennox 71W44 Limit Switch 319825-402 For the M611 seriesThe Lennox 71W44 Limit Switch is a critical OEM safety component engineered for precise thermal regulation in residential gas furnaces and air handlers. This L145 30F limit switch is designed to monitor discharge air temperatures, automatically breaking the electrical circuit if the internal plenum temperature exceeds the 145F safety threshold. Once the system cools to 115F, the switch features an automatic reset function to restore operation without