This solenoid is rated for operation in ambient temperatures up to 155°F (68°C)

Ensure the threaded nut is snug and the mica insulation remains intact

and debris that compromise system calibration

Common Questions: Can this relay replace the 42-19736-04

How do I know if my PTAC thermistor is bad

Lennox 99K63 Rollout Switch This solenoid is rated forThe Lennox 99K63 Rollout Switch is a critical safety component designed for precise thermal monitoring in residential and commercial gas furnaces. Engineered as a manual reset rollout switch, this part is calibrated to actuate at 250 degrees F (+ 12F), immediately interrupting the burner circuit if it detects flame rollout or excessive heat concentrations outside the combustion chamber. This OEM Lennox replacement part, also identified by part number