Description
The Trane CNT4821 is an essentialsafety device referred to as an automatic reset limit switch It is used to prevent overheating in HVAC equipment and more specifically in furnaces and air handlers. It employs the use of a bi-metal disc, which is a certain type of metal that changes shape when the climate changes. At 180°F the disc flexes and breaks the circuit to the heating element or compressor when the temperature around the limit switch is around the set limit. This self-stopping prevents any damage to your HVAC system by power from arising from the extreme temperature. The temperature drop cools the thermocouple and bi-metal disk which brings back the normal cycles of the system.
