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3.8Heating
3.8.1The Heating Element
The heating element is a porcelain enamelled steel plate, with a thick film resistive coating circuit printed onto the dry side. A gravity thermal fuse is mounted on the heater plate in series with the heating element circuit.
A large dropping resistor is also printed onto the heater plate which forms part of the controllers power supply.
The element is clamped in place by a lock nut and supports the motor at the base of the tub.
3.8.2 Heating the Water
The heater plate is positioned beneath the filter plate. A flow through water heating system is created during the wash cycle by water flowing through the filter plate, over the surface of the element and into the wash pump.
3.8.3 Maintaining the Temperature
A printed circuit board with a temperature sensitive thermistor is mounted on the heater plate. The sensor parts are unservicable and if they fail a new heater plate is required.
3.8.4 Over Heat Protection
The heater plate is only activated during a wash cycle, and is not used in the dry cycle. The temperature is monitored by the thermistor, and if a failure occurs with the electronic control of the heater plate, the over heat protection is effected by the thermal fuse on the heater plate.
The thermal fuse consists of a gravity fuse which is in series with the heater track. In an over heat situation the thermal fuse will melt and fall off the heater plate, disconnecting power to the element.
