Make sure that the gas train is properly installed by
checking for any fuel leaks.
The operator must use appropriate tools for instal-
lation.
See the accompanying instructions for the adjust-
ment of the gas train.
WARNING
4.8.4
Gas pressure
The Tab. J is used to calculate manifold pressure taking into ac-
count combustion chamber pressure.
Gas manifold pressure measured at test point 1)(Fig. 19), with:
•
combustion chamber at 0" WC;
•
burner operating at maximum output;
•
column 1: gas ring R2-R3)(Fig. 13) adjusted as indicated in di-
agram (Fig. 14);
•
column 2: pressure loss at gas butterfly valve 8)(Fig. 18) with
maximum opening: 90°.
Calculate the approximate maximum output of the burner as fol-
lows:
subtract the combustion chamber pressure from the gas pres-
sure measured at test point 1)(Fig. 19);
find the nearest pressure value to your result in column 2 for
the burner in question;
read off the corresponding output on the left.
Example with natural gas G20
–
Maximum output operation
–
Gas ring 2-5)(Fig. 13) adjusted as indicated in diagram
(Fig. 14)
–
Gas pressure at test point 1)(Fig. 19)
–
Pressure in combustion chamber
3.69 - 0.79
A maximum output of 1136 MBtu/hr shown in Tab. J corresponds
to 2.90" WC pressure, column 1.
This value serves as a rough guide, the effective delivery must be
measured at the gas meter.
The data of thermal output and combustion
head gas pressure are related to full open (90°)
gas butterfly valve.
WARNING
20026767
Installation
MBtu/hr
= 3.69" WC
= 0.79" WC
= 2.90" WC
20
GB
kW
720
211
949
278
1136
333
1327
389
1515
444
1706
500
1894
555
2085
611
p ("WC)
1
2
1.38
0.12
2.16
0.15
2.90
0.19
3.66
0.23
4.21
0.27
4.72
0.31
5.12
0.35
5.31
0.39
Tab. J
D2786
Fig. 19