Reducing The Max. 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 instrument
with a resolution of at least 0.1 mbar
(0.01 kPa) to check the supply pres-
sure.
7. Proceed as indicated in the following
table.
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 max. heating output

The maximum heating output can be
reduced in 25 % increments according to
system requirements.
1. Press MODE and
for 3 s.
"SERV" is displayed 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 close test nipple A with
the screw.
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.
Procedure
Do not commission the boiler. Notify your
gas supply utility or LPG supplier.
Start the boiler.
Install a separate gas pressure governor
upstream of the system and regulate the
flow pressure to 20 mbar (2.0 kPa) for
natural gas or 37 mbar (3.7 kPa) for LPG.
Notify your 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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