Viessmann Vitodens 111-W, Installation And Service Instructions Manual

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Rated heating output 26 kW
–
operation with LPG
Number of boilers 2 4 6
Correction factor (adjustable value) Flue length a (m)
0
1
≤
25
≤
6
2
–
> 6
≤
12
≤
8
3
–
> 12
≤
19 > 8
≤
10
4
–
> 19
≤
25 > 10
≤
13
5
– –
> 13
≤
16
6
– –
> 16
≤
20
Rated heating output 35 kW
–
operation with natural gas
Number of boilers 2 4 6
Correction factor (adjustable value) Flue length a (m)
0
1
≤
17
≤
4
2 > 17
≤
25 > 4
≤
10
≤
7
3
–
> 10
≤
15 > 7
≤
8
4
–
> 15
≤
21 > 8
≤
11
5
–
> 21
≤
25 > 11
≤
15
6
– –
> 15
≤
17
Rated heating output 35 kW
–
operation with LPG
Number of boilers 2 4 6
Correction factor (adjustable value) Flue length a (m)
0
1
≤
20
≤
5
2 > 20
≤
25 > 5
≤
9
≤
6
3
–
> 9
≤
14 > 6
≤
8
4
–
> 14
≤
20 > 8
≤
10
5
–
> 20
≤
25 > 10
≤
13
6
– –
> 13
≤
15
Note
The correction factor changes the boiler modulation
range.
Checking the combustion quality
The Vitodens 111-W is factory-set for natural gas. Dur-
ing commissioning or maintenance, the CO
2
and CO
have to be measured at the boiler flue adaptor test port
to check the flue integrity. Subject to the Wobbe index,
the CO
2
content fluctuates between 7.5 % and 10.5 %.
CO of up to 500 ppm during start-up is acceptable.
We recommend measuring the O
2
, as this value is
unmistakable regarding lambda (air/gas). The O
2
con-
tent fluctuates between 7.5 % and 3.2 %. The CO/CO
2
ratio has to be less than 0.004.
If the actual CO
2
or O
2
and CO values deviate from the
stated range, check the balanced flue system for
leaks. If the flue installation is OK, change the gas
valve.
Note
To prevent operating faults and damage, operate the
appliance with uncontaminated combustion air.
Commissioning, inspection, maintenance
Burner adjustment when connecting multiple…
(cont.)
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