20019893
22
GB
Installation
4.9.3
Gas pressure
The adjacent tables are used to calculate manifold pressure taking
into account combustion chamber pressure.
Gas manifold pressure measured at test point 1)(Fig. 19), with:
–
Combustion chamber at 0” WC
–
Burner operating at high fire
–
Natural gas
Calculate the approximate high fire output of the burner as follows:
subtract the combustion chamber pressure from the gas pressure
measured at test point 1)(Fig. 19).
Find the nearest pressure value to your result in the table for the
burner in question.
Read off the corresponding output.
Example for RLS 28/M
–
High fire operation
–
Natural gas (G20)
–
Gas pressure at test point 1)(Fig. 19)
= 1.92” WC
–
Pressure in combustion chamber
= 0.79” WC
1.92 - 0.79
= 1.13” WC
A high fire ouput of 796 MBtu/hr shown in table RLS 28/M corre-
sponds to 1.13” WC pressure, natural gas.
This value serves as a rough guide, the effective delivery must be
measured at the gas meter.
Tab. G
RLS 28/M
RLS 38/M
RLS 50/M
∆
p (“ WC)
MBtu/hr
G20
MBtu/hr
G20
MBtu/hr
G20
616
700
796
890
985
1079
1174
1232
0.68
0.87
1.13
1.41
1.73
2.07
2.45
2.70
882
985
1098
1212
1325
1440
1553
1666
0.46
0.57
0.71
0.87
1.04
1.23
1.43
1.64
1092
1250
1401
1553
1704
1856
2007
2198
0.58
0.76
0.96
1.18
1.42
1.68
1.97
2.36
Fig. 19
D2786
