Viessmann ES4.A5 OK, Operating Instructions Manual

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8
6167225 GB
Operation (cont.)
Operating instructions
Faults
Venting
Caution
Air in the water installation may damage
the appliance.
Vent the system after working on the
appliance or the water installation.
1. Switch off the power supply, e.g. at the
separate fuse or a mains isolator.
2. Open and close the hot water tap several
times to vent the water installation until a
constant, even flow of water is achieved.
3. Turn the rotary switch to the required
temperature.
4. Switch on the power supply.
No. Fault Background Remedy
1.
The appliance is not
heating the water
and the LED is not
illuminated.
Power supply fault. Check the fuses.
Fault with the rotary
temperature switch.
Replace the rotary
temperature switch.
(Heating contractor)
2.
The appliance is not
heating the water and
the LED is illuminated.
Fault with the heating
module.
Replace the appliance.
(Heating contractor)
Fault with the temperature
limiter.
Switch on the temperature
limiter or replace it.
(Heating contractor)
3.
The appliance is heating
the water and the LED is
not illuminated.
Fault with the LED.
Replace the LED.
(Heating contractor)
Operation (cont.)