22
Installation & Service Manual
Checking Gas Supply Pressure
GAS VALVE
MANOMETER
GAS SUPPLY PRESSURE
UNION
Figure 3-4_
Gas Supply Pressure
1.
Turn the power “OFF” at the main dis
con
nect
switch.
2.
Turn gas valve control knob(s) to the “OFF” position.
3.
The 500,000 Btu/hr model will have two gas valves. Turn
the gas valve control knob on each valve to the “OFF”
position.
4.
Shut off gas supply at the manual valve in the gas piping
to the appliance. If fuel supply is L.P. gas, shut off gas
supply at the tank.
5.
Remove the 1/8" hex plug, located on the “inlet” side of
the gas valve and install a fitting suitable to connect to a
manometer or magnahelic gauge. On two gas valve
models, remove the hex plug from the gas valve closest to
the gas sup ply connection. Range of scale should be
14" w.c. or greater to check inlet pressure. See FIG.’s 3-3
and 3-4 for location.
6.
Turn on gas supply at the manual valve, turn on L.P. gas
at tank if required.
7.
Turn the power “ON” at the main dis con nect switch.
8. Turn gas valve control knob to “PILOT”
po si tion on standing pilot models. Follow the “Lighting
Instructions” in Section 6 - Startup for standing pilot
models to light the pilot . Turn gas valve control knob to
the “ON” po si tion when the pilot is established. Turn
gas valve control knob(s) to the “ON” position on spark
ig ni tion models.
9.
Set the thermostat(s) to call for heat.
10. Observe the gas supply pressure with all burn ers firing.
Ensure inlet pressure is within specified range. Check gas
supply pressure with all other gas fired appliances in
operation to en sure prop er gas volume during periods of
peak gas usage.
11. If gas pressure is out of range, contact gas utility, gas
supplier, qualified installer or service agen cy to determine
necessary steps to provide prop
er gas pressure to the
appliance.
12. If the gas supply pressure is within the spec i fied range,
proceed with the following steps to return the appliance to
service.
13. Turn the power “OFF” at the main dis con nect switch.
14. Turn gas valve control knob to “PILOT” po
si
tion on
standing pilot models. Turn gas valve control knob(s) to
“OFF” position on spark ig ni tion mod els.
15. Shut off gas supply at the manual valve in the gas piping to
the appliance. If fuel supply is L.P. Gas, shut off gas supply
at the tank.
16. Remove the manometer and related fittings from the
“inlet” side of the gas valve, replace 1/8" hex plug in gas
valve.
17. Turn on gas supply at the manual valve, turn on L.P. Gas at
tank if required.
18. Turn the power “ON” at the main dis con nect switch.
19. Turn the gas valve control knob(s) to the “ON” position. If
the pilot is not burning, follow the “Light ing Instructions”
in Section 6 - Startup for standing pilot models to light the
pilot. Spark ignition models will au to mat i cal ly light the
pilot on a call for heat.
20. Set the thermostat to call for heat. The appliance is now
ready to operate.
IMPORTANT
Upon completion of any testing on the gas
system, leak test all gas connections with a
soap solution while main burners are
operating. Im
me
di
ate
ly repair any leak
found in the gas train or re
lat
ed
components.
Do Not
operate an appliance
with a leak in the gas train, valves or related
piping.
Check burner performance by cycling the system while you
observe burner response. Burners should ignite promptly.
Flame pattern should be stable, see the “Main te nance Section -
Normal Flame Pattern”. Turn system off and allow burners to
cool, then cycle burners again to en sure proper ignition and
flame characteristics.
3
Gas connections
