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Instructions for user - MCX - 801052 - January 2020 v1.20 Art.no: 9120-15036
8. Troubleshooting and service
Repairs must only be carried out by
authorised professionals.
If a fault in your appliance cannot be
rectified with the aid of this table,
please contact the service organisa-
tion of your importer or the Central
Customer Service Department. Please
have the details of the typeplate at
hand.
This instantaneous water heater was manufactured conscientiously and checked sev-
eral times before delivery. First attempt to switch the house fuses off and on again in
order to reset the electronics. Next, try to remedy the problem with reference to the
following table. In doing so, you will avoid unnecessary expense of customer service
assistance.
Fault Cause Action
No water flows Water supply is turned off Open the main water valve and the
shut-off valve
Water flows
more slowly than
expected
The flow controller is not
fitted Fit the special flow controller
Water pressure is not suf-
ficient
Check the water flow pressure or
let check the water flow adjust-
ment by an authorized technician
Dirt in the pipes
Remove any dirt from the filter,
valves and taps / check the techni-
cal data
The heater switch-
es itself on and off
Water pressure is varying,
flow rate is too low
Remove any dirt / increase the flow
water pressure, close other taps,
open the shut-off valve further
Water remains
cold
Water pressure is not suf-
ficient
Let adjust the water flow by an
authorized technician, open the
shut-off valve, fit the special flow
controller, check water pressure
Dirt Remove dirt from the inlet and
outlet
Hot water tem-
perature varies
Supply voltage varies Check the supply voltage
Water connections mixed
up Check installation
Hot water tempe-
rature too low and
one LED flashes
slowly
Flow rate is too high or
inlet temperature is too
low
Adjust the flow either at the tap,
the valve or have the flow adjusted
by a authorized technician
One LED flashes
rapidly and water
remains cold
Defective temperature
sensor
Replace temperature sensor
(authorized technician)
Defective heating ele-
ment
Replace heating element (author-
ized technician)
All LEDs flash
rapidly and water
gets warm
Defective control panel
cable
Reposition control panel connector
(authorized technician)
Replace control panel (authorized
technician)
All LEDs flash
rapidly and water
remains cold
Defective power unit Contact Zip customer service
LED turns off
shortly after key-
press
Keylock is active Deactivate keylock (see page 8)