Gas Valve And Burner Set-Up - NTI FTG 600 Installation And Operation Manual

FTG

9.0 GAS VALVE AND BURNER SET-UP

Set-up of the
perform the set-up correctly may result in incorrect operation, component failure,
property damage, serious injury or death.
Gas Line Pressure
The boiler gas valve is equipped with a line pressure test port; see Figure 9-1. Use the following procedure to
measure the gas line pressure to the boiler to ensure if falls within the range given in Table 9-1:
1. Turn the supply of gas to the boiler off.
2. For models FTG 600-1400, use a 3/16 in. hex wrench to remove the plug from the inlet flange of the gas
valve, and install a 1/8 NPT x hose barb adapter suitable for connecting the tubing of the gas pressure
manometer being used to measure gas line pressure. Models FTG 2000-2400 encorporate a bleed screw on
the inlet flange of the gas valve, open it approximately 1-1/2 turns. See Line Pressure Test Port in Figures
9-1(a) and 9-1(b).
3. Slide the gas pressure manometer tubing over the hose bard adapter located on the inlet flange of the gas
valve (bleed screw fitting for models FTG 2000-2400); connect the other end of the tubing to the gas
pressure manometer. Ensure both ends of the tubing make a tight connection.
4. Open the supply of gas to the boiler and check for gas leaks.
5. Observe the line pressure under static conditions and compare it to Table 9-1. The pressure will be greatest
under static conditions.
6. With all other gas appliances in the application running, operate the burner to the maximum firing rate (see
Table 9-2) and compare the observed line pressure with Table 9-1. The pressure will be lowest during the
maximum flow of gas.
7. Adjust the gas line pressure to ensure the parameters in Table 9-1 are attained under all conditions (see
NOTICE below). If possible, adjust the line pressure to the "Nominal/Desired" value listed in Table 9-1,
while the unit is operating at the maximum modulation rate, see Table 9-2.
8. Continue observing the gas line pressure until the completion of the combustion analyses, in case
adjustments need to be made.
9. Upon completion of the line pressure testing, turn the gas supply off, and then reinstall the Line Pressure
Test Port plug, applying appropriate thread sealant to the threads prior to installing. For models FTG 2000-
2400, close the bleed screw. Turn gas on and check for leaks.
The line pressure is a function of the gas supply and is affected solely by field provided
parameters such as line size and regulator settings. Under no circumstances can the boiler
gas valve influence or be used to adjust the gas line pressure.
Failure to properly re-install the Line Pressure Test Port plug (FTG 600-1400), or close
the Line Pressure Test Port bleed screw (FTG 2000-2400) will cause severe leakage of
gas, resulting in a fire or explosion causing property damage, serious injury or death.
Table 9-1 Line Pressure and Combustion Parameters
Line Pressure (inches w.c.)
Gas
Nominal/
Desired
Natural 7
Propane 11
Notes:
1
Combustion calibration must only be performed with the burner operating at maximum modulation rate.
2
Combustion values listed are for burner operation at maximum modulation rate; CO
minimum modulation rate.
3
When tested at minimum modulation rate, the CO
4
The Offset Pressure for models FTG 2000-2400 converted to Propane, must be checked, and if necessary adjusted, in
accordance with the procedure detailed in Figure 9-2.
FTG
gas valve must be performed by a licensed Gas Technician. Failure to
(inches w.c. / [Pa])
Min. Max.
4 10.5 -0.01 to 0 / [-3 to -1]
8 13 -0.04 to -0.03 / [-10 to -8]
must be 0.5-1.0% lower than CO
2
│Installation & Operation Manual
Offset Pressure
4
Min.
and CO values will be lower at
2
2
1,2,3
CO (%)
2
Max. CO
(ppm)
Max.
8.7 9.5 175
10 10.8 175
at maximum modulation rate.
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