Reducing The Maximum Heating Output; Matching The Circulation Pump Rate To The Heating System - Viessmann VITODENS 111-W Installation And Service Instructions Manual

Checking the static pressure and supply pressure
Supply pressure (flow pressure)
For natural gas
Below 10 mbar (1.0 kPa)
10 to 33 mbar
(1.0 to 3.3 kPa)
Above 33 mbar (3.3 kPa)

Reducing the maximum heating output

The maximum heating output can be reduced accord-
ing to the system requirements.
01. Tap MODE.
02. / until CONFI flashes.
03. OK to confirm.
"P" appears in the l.h. display area. The r.h. dis-
play area flashes.
04. Use / to select "12".
05. OK to confirm.
"1" flashes in the l.h. display area.
06. Use / to select "2".

Matching the circulation pump rate to the heating system

In its delivered condition the circulation pump rate is
set to the following values:
■ For DHW heating: Speed 100 %
■ For heating mode without outside temperature
sensor:
Rated heating output in kW
Speed in %
The speed cannot be changed.
For LPG
Below 25 mbar (2.5 kPa)
25 to 57.5 mbar
(2.5 to 5.75 kPa)
Above 57.5 mbar
(5.75 kPa)
26 35
90 100
Commissioning, inspection, maintenance
(cont.)
Steps
Do not commission the boiler. Notify the gas supply util-
ity or LPG supplier.
Start the boiler.
Install a separate gas pressure governor upstream of
the system and set it to the nominal pressure (see type
plate). Notify your gas supply utility or LPG supplier.
07. OK to confirm.
The value of the selected maximum heating out-
put, in % of the upper heating output, flashes in
the r.h. display area.
Example:
≙
■ 25 25 %
≙
■ 100 100 %
08. Use / to select the required max. heating output.
09. OK to confirm. The selected value is adopted.
10. Check the selected heating output by measuring
the gas throughput.
For heating mode with outside temperature sen-
■
sor:
Rated heating output in kW
Min. speed in %
Max. speed in %
The maximum speed can be changed. See the fol-
lowing chapter.
26 35
65 65
90 100
23