Temperature limiters are frequently referred to as either
- Safety thermostats
- Over-temperature cutouts
- Button thermostats
They are a simple device that usually looks something like this:
Temperature limiters either make or break the circuit (close or open) at whatever temperature the device is rated at. They are used as a safety device to ensure the temperature of surrounding cabinetry or components does not exceed a safe level so the correct device for the appliance is crucial.
The two main types (normally closed and normally open) have different jobs to do to maintain the external temperature of the appliance:
The normally closed type (N/C) is used to open (break) the circuit if the temperature is exceeded, resulting in all elements being disconnected and the oven inoperable until the temperature drops.
The normally open type (N/O) is used to close (make) the circuit to the cooling fan (located outside the oven cavity near the control panel) when the temperature exceeds the set value. This will keep the fan running irrespective of any elements being used and often runs on for several minutes after the oven has been used.
It is highly recommended that only the genuine replacement part is used. Where this is not possible care must be taken to match to another certified limiter with identical electrical and temperature characteristics.