Initial Start-up and Service
25
Steps
(continued)
26. Clock natural gas meter
I
nitial start-up
S
ervice
Clock natural gas meter to verify input.
1.
Ensure all other gas equipment
served by the meter is turned off
during timing of gas input to the
Vitodens 200-W, WB2B boiler.
2.
Measure the time in seconds it takes
for the boiler to use 10 ft.
3
of gas.
Divide 3600 x 10 by the number of
seconds and you get the number of
ft.
3
of gas used per hour. Multiply
this number by the heating value of
the gas to obtain Btu per hour input.
For example:
A Vitodens 200-W, WB2B 105 boiler
(370 000 Btu/h input) requires 97
sec. to use 10 ft.
3
of natural gas.
After contacting the local utility, you
will find the heating value is
1000 Btu per ft.
3
.
Therefore,
3,600 sec./h x 10 revolutions
36,000/97 x 1000
≅
370 000 Btu/h
input. The boiler input is correct.
Burner input formulas
(for low altitude only):
INPUT=(3600
÷
t) x 1000 where
t=TIME (sec.) for 1 ft.
3
INPUT=(3600 x .01 x 1000 x
35.31)
÷
T where
T = TIME (sec.) for .01 m
3
natural
gas
A boiler underfired by 5% is
acceptable. Do not overfire the boiler
.
5
4
4
3
2
0
7
v
1
.5
IMPORTANT
Always contact your gas utility to
obtain the correct heating value before
clocking the meter.
CAUTION
