Fisher & Paykel DD247 Dishwasher User Manual


 
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3.8 Heating
3.8.1 The Heating Element
The heating element is a porcelain enamelled steel plate, with
a thick lm 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 lter plate. A ow through water heating system is created during the
wash cycle by water owing through the lter 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 eected 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 o the heater plate, disconnecting power to the element.