IMAGE COMING SOON
OEM Guaranteed
Same-Day Ship
30-Day Returns
Secure Checkout
The Lennox 96W57 is a genuine OEM Therm-O-Disc 100503-10 defrost thermostat engineered to monitor outdoor coil temperatures and activate the defrost cycle at the correct threshold, keeping your Lennox heat pump running at peak efficiency. A failed defrost thermostat can result in heavy ice buildup on the outdoor unit, diminished heating capacity, and potential compressor damage over time. Replace it with this exact OEM part to restore proper defrost operation and protect your Lennox system investment.