Drain Cycle; Filter Plate; The Filter System; Removing And Cleaning The Drain Filter And Filter Plate - Fisher & Paykel DishDrawer DD24D Series Service Manual

3.9

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 five bladed impellor pushed into a spline on the lower end
of the rotor shaft.
The drain pump housing, which incorporates an inlet and outlet pipe, is welded to the motor
housing, hence captivating the motor. The inlet pipe plugs straight into the drain sump in the tub
and is sealed there by a small 'O' ring. The outlet pipe has a non-return flap valve to prevent
soiled water returning to the tub.
The drain hose is an extruded blow moulded hose that is routed over the link assembly and exits
out of the base of the product and is connected to a domestic drain.
The pump speed during the drain cycle is approximately 4200 rpm. In hardware output diagnostics
test mode it is set to the same speed to aid diagnosing drain problems.
On a double product, the drain motor on the tub which is not being used will run for a short time
during the final drain phase of a wash cycle. This is to remove any drain water that may have back
flowed in to the unused tub. This concurrent drain will not happen if the unused tub is open. If the
user presses the power button after water has been placed in the tub, the product will initiate a
"power off" drain and empty the tub.
3.10

Filter Plate

The filter plate is a stainless steel disk positioned below the dish rack and spray arm and
completely encompasses the base of the tub.
3.10.1

The Filter System

The tub has vanes that swirl the water around and over the filter plate. At the front of the tub,
located as part of the filter plate, is the drain filter. Large soils collect in the drain filter and only
smaller soils flow through its micro-mesh filter, eliminating re-depositing of soil during the wash.
The drain filter should be regularly checked and cleaned.
3.10.2

Removing and Cleaning the Drain Filter and Filter Plate

The drain filter can be emptied with the dish rack in place by removing the cutlery basket and
opening the plastic section of the dish rack. The filter plate is removable for cleaning by removing
the dish rack and spray arm and unlocking the locknut by turning it anti-clockwise. Turning it too
far will also release the rotor and may allow it to be lifted out with the filter plate.
3.11

Drying Cycle

Immediately after water from the final hot rinse has been drained from the tub, the drying cycle
begins.
The drying fan draws air through the vent in the rear into the tub where it absorbs water from the
dish load. The moisture-laden air is then mixed with a larger quantity of ambient air (drawn from
the kitchen), to minimise the amount of vapour visible when air is exiting from the bottom of the
drawer front.
A flap valve is located in the fan housing. This is closed to prevent moist air from entering the
space behind the door panel during the wash, reducing the possibility of damage to the controller
and LCD. It opens whenever the fan is running.
The fan runs continuously during the drying cycle for various times depending on the program
selected, and will restart if the tub is opened and closed again.
complete (when the appliance beeps and the LCD shows 00), the lid drives up, and the fan
continues to run for anything up to 120 minutes depending on the program, but will not restart if the
tub is opened or if a button is pressed.
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599735A
After the wash program is