Fisher & Paykel DishDrawer DD605 Service Manual page 42

599447A
C1 Water Softener Diverter Valve
In hardware output diagnostics test mode:
FU – turn the fill water valve on
P2 – turn the motor drain on
C1 – water softener diverter valve
On – water bypasses the resin tank
Off – water flows through the resin tank
C2 Water Softener Brine Pump
Turn the brine pump on in diagnostics mode. Observe a small quantity of water
(approx. 30 ml per min.) flowing out the bottom of the dispenser (drop the
dispenser door down to observe this.) Observe a change in the water level
(approximately 120ml per 4 min.) in the salt reservoir. The reservoir should pump
dry of water in this time.
Note: - Fill the salt reservoir with salt (and then water if not already) before
performing this test.
Pipe Interrupter (Air Break) Function
A critical component in the performance of the water softener is the pipe
interrupter air break (PI). There is a certain amount of spray leakage from the PI,
which is used to provide water to the salt reservoir.
If the spray is inadequate, there will be insufficient water in the salt reservoir to
make brine.
If there is too much spray, then the excess bypasses the water softener and
defeats the softening process by pouring untreated water straight into the tub.
To check that the amount of spray is appropriate:-
Fill the salt reservoir with water.
In diagnostics mode, turn on the fill water valve and the motor drain. Water will
flow out of the dispenser into the tub, as well as out of the water softener overflow
into the tub.
Observe the flow from the water softener overflow (beside the dispenser). There
should be a trickle (25-100 ml per minute). With experience you can guess what is
appropriate. If the trickle is outside these rates, replace the water softener, as the
PI is faulty.
To check that there is water in the salt reservoir, remove the drawer front and
observe the level of water in the tank. (A quick way to check that there is water in
the salt reservoir is to remove the salt bung and test the water level by placing
your finger down through the opening.)
Detergent or Rinse Aid in the Water Softener
If detergent or rinse aid is poured in to the salt reservoir it will destroy the water
softener. This could also happen if the salt bung is left off or falls out. Evidence of
this could be white streaks through the resin.
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