Tub; During A Power Failure; Filling; Water Inlet - Fisher & Paykel DishDrawer DD605 Service Manual

599447A

3.6.3 During a Power Failure

If power to the DishDrawer™ fails with the lid down, the tub can still be forced open manually if access is required. It is
very difficult however to close the tub again without raising the lid. The lid actuators can be wound up manually with the
tub fully removed. Failure to raise the lid before closing the drawer can result in the lid seal being damaged.
3.7

Tub

The tub is the main cavity where all the wash activity occurs. The tub is a polymer plastic receptacle that has a wash
pump and spray arm at the base. The tub also has guide vanes around its walls which direct falling water from the wash
cycle in a clockwise direction around the filter plate. This clears the filter plate of food particles and washes them into the
sump where they are trapped by the drain filter or pumped out during the drain cycle.
3.8

Filling

3.8.1 Water Inlet

The tub of the DishDrawer™ fills by a single water inlet hose. Hot water connection is recommended for USA and
Japanese products and cold water connection recommended for the Australasian, UK and European products. From the
connection to the water supply tap in the kitchen, the inlet hose enters the cabinet of the dishwasher at the base, onto a
dual water valve. Each tub is supplied water independently via one of the dual valve coils and a fill hose that runs
through a customised link assembly at the back of each tub and travels along the base of the tub under the wiring cover
to the front. At the front of the tub, the fill hose connects to the water softener (if fitted) then to the detergent dispenser
which directs water into the tub, firstly through the pre-rinse section of the dispenser for the pre-rinse cycle and secondly
through the main wash section for all other cycles.
In a double product the controller allows only one inlet valve to operate at a time. This has been done to reduce EMC
emissions. The top tub has priority. This restriction does not apply in diagnostics mode.

3.8.2 Dispensing Detergent and Rinse-aid

The dispenser is mounted in the front wall of the wash tub.
The detergent dispenser consists of two detergent chambers, one for pre wash and the other for the main wash.
The detergent dispenser door is opened manually for detergent loading and then manually closed ready for the detergent
to be transported to the wash tub by the inlet water. To enable each detergent chamber to be dispensed separately, an
inlet water diverter valve controlled by the electronics is required.
Additionally, a positive displacement pump unit and storage tank is incorporated within the dispenser to supply rinse aid.
The rinse aid dispensed volume can be adjusted by the customer in option adjustment mode. A glowing red light on the
tank filler cap indicates an empty rinse aid tank. The pump frequency is 1 Hz, and makes a slight beeping sound.

3.8.3 Amount of Water

The tub fills with approximately 2.5 litres / 0.8 US gallons of water, almost level with the base of the spray arm. Once this
level is reached, the wash pump (which has load-sensed the fill via the electronics) becomes primed and pumps the
water through the spray arm causing it to rotate. The load on the wash pump is constantly monitored throughout the
wash cycle and the water level adjusted if necessary. If the wash pump loses prime, the electronics will top up the water
level by opening the fill valve for approx. 5 seconds. It will do this up to 3 times before carrying on regardless.

3.8.4 Flood Protection

A flood sensor mounted on the side of the mains filter housing provides flood protection. If a flood is detected, the drain
pump will run and a F1 fault code will be signalled to the customer
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