Rooms Are Too Cold - Viessmann VITODENS Operating Instructions Manual

What to do if...

Rooms are too cold

Cause
The heating system is switched off.
Control unit incorrectly adjusted.
■
The remote control (if installed) is set incorrectly.
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Separate operating instructions
The DHW cylinder is heated.
No fuel.
"Combustion controller" is displayed.
"Fault" is displayed. The red fault indicator flashes.
"Screed drying" is active.
The mixer motor is faulty.
32
Remedy
Turn on the ON/OFF switch (see diagrams from
■
page 16).
Switch on the mains isolator if installed (outside the
■
boiler room).
Reset the MCB in the power distribution board (main
■
domestic MCB).
Central heating must be enabled.
Check settings and correct if required:
Operating program (see page 18)
■
Room temperature (see page 18)
■
Time (see page 26)
■
Central heating time program (see page 18)
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Heating curve (see page 19)
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Wait until the DHW cylinder has been heated up.
Reduce the DHW draw-off rate or temporarily reduce
the standard DHW temperature as required.
Note
In the case of operation with an instantaneous water
heater, stop DHW draw-off.
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.
Press R (see page 16).
Acknowledge the fault (see page 30).
Danger
If faults are not rectified, they can have life
threatening consequences.
Do not acknowledge fault messages several
times in quick succession. Notify your heating
contractor if a fault recurs. Your heating contrac-
tor will be able to analyse the cause and rectify
the fault.
Check what type of fault it is. Acknowledge the fault
(see page 30). If necessary, notify your heating contrac-
tor.
No action required.
After expiry of the screed drying time, the selected op-
erating program will become active.
Adjust the mixer manually.