Reducing The Maximum Heating Output - Viessmann VITODENS 050-W Installation And Service Instructions Manual

Further details regarding the individual steps
6. Check the supply (flow) pressure.
Set value:
■ Natural gas: 20 mbar (2.0 kPa)
■ LPG: 37 mbar (3.7 kPa)
Note
Use a suitable measuring device
with a resolution of at least
0.1 mbar (0.01 kPa) to check the
supply pressure.
7. Implement measures as indicated
in the table below.
Supply pressure (flow pressure)
For natural gas
Below 17.4 mbar
(1.74 kPa)
17.4 to 25 mbar
(1.74 to 2.5 kPa)
Above 25 mbar
(2.5 kPa)

Reducing the maximum heating output

The maximum heating output can be
reduced in 25 % increments according
to system requirements.
1. Press MODE and
and hold for 3 s.
"SERV" appears on the display
and "I" flashes.
For LPG
Below 25 mbar
(2.5 kPa)
25 to 47 mbar
(2.5 to 4.7 kPa)
Above 47 mbar
(4.7 kPa)
simultaneously
Commissioning, inspection, maintenance
(cont.)
8. Shut down the boiler, close the gas
shut-off valve, remove the pressure
gauge and tighten the screw in test
connector A.
9. Open the gas shut-off valve and
start the appliance.
Danger
Gas escaping from the test
connector leads to a risk of
explosion.
Check gas tightness at test
connector A.
Steps
Do not commission the boiler. Notify the
gas supply utility or LPG supplier.
Start the boiler.
Install a separate gas pressure governor
upstream of the system and set the flow
pressure to 20 mbar (2.0 kPa) for natu-
ral gas or 37 mbar (3.7 kPa) for LPG.
Notify the gas supply utility or LPG sup-
plier.
2. Use / to select "2" and confirm
with OK.
"00" flashes on the display (corre-
sponds to 100 % burner output).
3. Use / to select the required
burner output and confirm with OK.
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