the solenoid valve remains closed

or equipment damage

this cast iron check valve allows for internal component maintenance without breaking brazed joints

Industrial Grading: Engineered to withstand the high-temperature conditions typical of commercial condenser units

Lennox 73K21 Limit Switch 320735-701 the solenoid valve remains closedThe Lennox 73K21 Limit Switch is a critical safety component designed for precise thermal regulation within residential gas furnaces and air handlers. Engineered as a Lennox replacement part, this 145 175F AUTO limit switch monitors discharge air temperatures to prevent heat exchanger overheating. It operates on a normally closed circuit that opens if temperatures exceed the 175F threshold, effectively cutting power to the gas valve or ignition