Fisher & Paykel DishDrawer DD60 Service Manual page 32

4 TECHNICAL OVERVIEW
4.13.2 Heating the Water
The heater plate is situated below the water duct
cover. The water is passed over the heating element
during the wash cycle via the duct. The heated water
is then picked up by the motor rotor and distributed
to the wash load via the spray arm.
4.13.3 Maintaining the Temperature
The water temperature is monitored by a
thermistor situated in the base of the tub.
It is connected to the wash controller, which
monitors the water temperature.
4.14 Drain Cycle
The drain pump is a self priming centrifugal pump that
only pumps when the motor is rotating in the drain
direction (anti-clockwise). It has a 5 blade impellor
pushed onto a spline on the lower end of the rotor
shaft.
outlet
The drain pump housing, which incorporates an inlet
and outlet pipe, is welded to the motor housing, hence
captivating the motor.
inlet
The inlet pipe plugs straight into the drain sump in the
tub, and is sealed by a small o-ring.
The outlet pipe has a non-return valve to prevent soiled
water returning to the tub.
The drain hose is an extruded blow moulded hose that
is routed through the link assembly and exits out the
base of the product and is connected to the domestic
drain.
The drain speed during the drain cycle is approx 5000
rpm. In the hardware output diagnostic mode, it is set
at the same speed as drain, to help diagnose drain
problems.
drain
impellor
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