Sub-Zero Freezer Defrost Heater & Terminator Repair Kit for BI Series
Evaporator Defrost Heater & Temperature Safety Switch Set
BI-30U, BI-30UG, BI-30UA, BI-36U, BI-36UG, BI-36UA +4 more View all 10 compatible models Show fewer compatible models
BI-30U, BI-30UG, BI-30UA, BI-36U, BI-36UG, BI-36UA, BI-36UFD, BI-36UFDID, BI-42UFD, and BI-42UFDIDEvery order is manually reviewed by our parts experts before processing. If you provide your model or serial number and we ship the wrong part, we’ll cover the return or exchange, including a prepaid return label.
OEM part description
This genuine Sub-Zero freezer defrost heater and terminator switch work together in the automatic defrost system. During the defrost cycle, the heater warms the freezer evaporator to melt accumulated frost, while the terminator monitors evaporator temperature and opens the heater circuit once the evaporator has warmed sufficiently. Expert Appliance Pro supplies both components as a technician-recommended repair set because the heater and terminator are part of the same evaporator defrost circuit and can cause similar frost-related symptoms when they fail.
Part details
A failed defrost heater or terminator can allow frost and ice to continue building on the freezer evaporator. As the evaporator becomes blocked, airflow can decrease and the freezer may begin running warmer, running longer than normal, or developing heavy frost behind the interior freezer panel. Replacing the heater and terminator together addresses both components in the evaporator heating circuit rather than installing a new heater while reusing an older temperature-control switch.