Section I: Installation
To check inlet pressure - with other equipment on
the same line turned on and turned off:
Check the inlet pressure with all equipment on the same
gas supply line turned on and turned off.
1. Shut off the gas supply and remove the cover panel of
the control console. Remove the inlet pressure tap and
connect the pressure gauge or manometer (See Fig. 1.4).
2. Turn the gas supply back on. Light the main burner.
Turning the primarythermostat dial above room
temperature lights the main burner.
3. Record the inlet pressure readings on the Installation
Checklist for Warranty Validation. Be sure to take readings
with other equipment on the same line turned on and
turned off.
4. Reverse the procedure in step 2 to turn off the main
burner and shut off the gas supply before disconnecting
the manometer or pressure gauge.
5. Replace the inlet pressure tap plug.
Important!
Always shut off the gas supply at the manual
valve in the gas supply piping to the unit (or at the tank
for LP gas), before removing the inlet pressure tap plug to
connect or disconnect a pressure gauge or manometer.
Inlet Pressure Too High?
If natural gas pressure exceeds
7” water column or LP gas pressure exceeds 14” water
column, then a pressure-regulating valve must be
installed in the gas supply line.
I
nlet Pressure Too Low?
If natural gas pressure is below
5” water column or LP gas pressure is below 12” water
column, then the installer must determine the problem.
Too much equipment may be on the same line or a larger
gas supply line may be required.
Inlet pressure must be correct before checking the outlet
pressure.
Fig. 1.3 Pressure Regulator Specification Pressures
(in Inches Water Column)
Gas Valve
Type
Type of
Gas
Nominal Inlet
Pressure Range
Factory Set
Nominal Out-
let Pressure
Adjustment
Setting Range
Intermittent
Pilot
Natural
5.0 - 7.0” w.c.
3.5” w.c.
3 - 5
LP
12.0 - 14.0” w.c.
9.0” w.c.
8 - 12
Checking For Gas Leaks
WARNING:
Do not permanently supply gas to the unit until the gas
lines have been pressure tested. Faulty operation and
even equipment damage will result if the gas supply falls
below requirements.
The equipment and its individual shut-off valve must be
disconnected from the gas supply piping system during
any pressure testing of that system at test pressures in
excess of 1/2 psi (3.5 kPA).
The equipment must be isolated from the gas supply
piping system by closing its individual manual shut-off
valve during any pressure testing of that system at test
pressures equal to or less than 1/2 psi (3.5 kPA).
1. Turn on the main gas supply. With burner off, douse
the pipe connections up stream of the ignition system
control with a rich soap and water solution. Bubbles
indicate a gas leak. If a leak is detected, tighten pipe
connections. Replace the part if the leak cannot be
stopped.
2. With main burner in operation, douse pipe joints
and control inlet and outlet with rich soap and water
solution. If another leak is detected, tighten joints and
pipe connections. Replace the part if the leak cannot be
stopped.
Gas Control - Pressure Verification
Using a pressure gauge or a manometer, the installer must
record the gas pressure at both the inlet and outlet of the
ignition system control—first with all equipment on the
same gas line turned on, then with all equipment turned
off. These readings are necessary for your installation and
warranty records. Gas pressure input and output ratings
for your equipment are listed on the unit’s nameplate.
Acceptable pressure ranges are provided below. Do not
exceed these ratings. NOTE: Since outlet pressure is
dependent upon proper inlet pressure,
inlet pressure must
be checked first.
6
