MFC Series Boilers User Manual
CHAPTER 9 – MFC 4000/6000 GAS ONLY BURNER
P
OMM-0104_94
AERCO International, Inc.
•
100 Oritani Dr.
•
Blauvelt, NY 10913
Page
95
of
170
GF-146
Ph.: 800-526-0288
12/29/2015
9.2 Gas Supply Pressure
The table in Figure 9-5 shows minimum load losses at combustion head (
∆
p1) and gas
butterfly valve (
∆
p2) depending on the maximum burner output operation with natural gas.
∆
p1 -
Gas pressure is measured at the test point (1) in Figure 9-5, with:
•
Combustion chamber at 0 mbar.
•
Burner working at maximum output.
•
Ring nut (2) in Figure 9-3 adjusted as in the diagram of Figure 9-2.
∆
p2
- Load loss at gas butterfly valve (2) in Figure 9-5 with maximum opening: 90°.
Figure 9-5: MFC 4000-6000 Natural Gas Supply Pressure Test Points and Chart
Figuring Burner Output
9.2.1
Figuring Burner Output
To know the
approximate output
at which the burner is operating at its maximum:
1. Subtract the combustion chamber pressure from the gas pressure measured at test point (1)
in Figure 9-5.
2. In the table in Figure 9-5 find the pressure value closest to the result you want; read the
corresponding output on the left.
Maximum Output Formula Example:
•
Natural gas
•
Gas Pressure at Test Point 1 = 4.09” WC
•
Pressure in combustion chamber = 1.14“ WC
4.09 – 1.14 = 2.95 “WC
A maximum output of 4166 MBtu/hr corresponds to 2.95” W.C. pressure.
This value serves as a rough guide; the effective delivery must be measured at the gas meter.
