Rooms Are Too Hot; There Is No Hot Water - Viessmann VITODENS Operating Instructions Manual

What to do if...

Rooms are too hot

Cause
Control unit or remote control incor-
rectly adjusted
Control unit fault: The display shows
"U", and the red fault indicator flashes

There is no hot water

Cause
The heating system is switched OFF
ON indicator "8" (green) OFF
Control unit incorrectly adjusted
No fuel
Control unit fault: The display shows
"U", and the red fault indicator flashes
Burner fault: The red fault indicator on
the control unit flashes, and "E" is dis-
played
20
Remedy
Check and, if required, correct adjust-
ments (see page 11 or the operating in-
structions of the remote control).
Check the type of fault (see page 17)
and notify your heating contractor
Remedy
Switch system ON/OFF switch "8"
ON (see page 10)
Switch the main isolator ON, if
installed (outside the boiler room)
Check and, if required, reset/replace
the MCB/fuse inside power distribu-
tion (main domestic circuit breaker/
fuse)
Check settings and correct, if required:
DHW heating must be switched ON
(see page 11)
DHW temperature (see page 14)
For LPG:
Check the fuel stock and re-order, if re-
quired.
With natural gas:
Open the gas shut-off valve and check
with your gas supply utility, if required.
Check the type of fault (see page 17)
and notify your heating contractor
Press burner fault reset "E"; if that at-
tempt to start also fails, notify your
heating contractor.