Dometic RO400 - Page 29

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Symptom
Possible error
codes
Check/Action Remedy
Intermittent start and 
stop.
Leakage in a section
of the pure water
system located after
the water purier.
Too high counter
pressure in the pure
water line.
Internal leakage.
<Not displayed>
Is the faucet/valve closed?•
If a faucet is used, check if •
there is a droplet hanging or
if there is a slow production
of droplets.
Replace the existing pure •
water hose with a new hose
with a valve. Use the valve
to see if the problem is
solved.
Reduce pressure drop in the •
pure water line.
Check the pure water con-•
nection for leakages
Check the lters and lter •
containers for signs of
water.
Remove the cover and check •
for signs of water, e.g. in the
accumulator connection, the
outlet pressure sensor con-
nections and the TDS-sensor
connection.
If the problem is solved with the new valve,
the problem is most likely due to a leakage
in a section of the pure water system after the
water purier - try to detect the location of the
leakage.
If the faucet is slowly leaking, remove the
faucet cover and turn the screw. For further
information, please refer to the product’s user
manual.
If the counter pressure is too high, e.g. in a
faucet or a valve on the pure water line, this
may result in a too high pressure in the water
line. This causes the outlet pressure sensor to
stop the pump.
Change the leaking component.
If no leakage is found, the pure water outlet
valve should be changed due to a defect check
valve inside the pure water valve.

Can be displayed
in various ways.
A broken PCB can result in numerous dif-
ferent error codes and symptoms. If a fault
cannot be located, try to change the PCB and
test again.
 
motor.
Too high counter
pressure in the pure
water line.
Time to change
lter II.
Change lter II• If lter II change is indicated, the motor start
is delayed by 3 seconds.
TROUBLESHOOTING
a)
c)
a)
b)