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 is incor-
rectly adjusted.
"Fault" is displayed, and the red fault
indicator flashes.
Mixer motor faulty.

There is no hot water

Cause
The heating system is off.
Control unit or remote control incorrectly
adjusted.
No fuel.
"Fault" is displayed, and the red fault
indicator flashes.
38
Remedy
Check settings and correct if required:
■ Room temperature (see page 18).
■ Time (see page 30).
■ Time program (see page 19).
Scan and acknowledge the type of fault
(see page 35). If necessary, notify your
heating contractor.
Adjust the mixer manually.
Remedy
■ Switch the ON/OFF switch ON (see dia-
grams from page 15).
■ Switch ON the mains isolator, if instal-
led (outside the boiler room).
■ Reset the MCB in the power distribution
board (main domestic MCB).
Check settings and correct if required:
■ DHW heating must be enabled (see
page 25).
■ DHW temperature (see page 25).
■ Time program (see page 26).
■ Time (see page 30).
With oil/LPG:
Check the fuel reserves and re-order if
required.
With natural gas:
Open the gas shut-off valve. If necessary,
check with your gas supply utility.
Scan and acknowledge the type of fault
(see page 35). If necessary, notify your
heating contractor.