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boss of the valve.
5. Turn ON the gas supply.
6. Turn on power and energize main (M) solenoid. Do
not energize the HI solenoid.
7. Measure gas manifold pressure with burners firing.
Adjust manifold pressure using the Manifold Gas
Pressure table.
8. Remove regulator cover screw from the low (LO)
outlet pressure regulator adjust tower and turn screw
clockwise to increase pressure, or counterclockwise
to decrease pressure.
9. Energize main (M) solenoid as well as the HI
terminal.
10. Remove regulator cover screw from the HI outlet
pressure regulator adjust tower and turn screw
clockwise to increase pressure, or counterclockwise
to decrease pressure.
11. Turn off all electrical power and gas supply to the
system.
12. Remove manometer hose from outlet pressure boss.
13. Turn outlet pressure test screw in to seal pressure
port (clockwise, 7 in-lb minimum).
14. Turn on electrical power and gas supply to the
system.
15. Turn on system power and energize valve.
16. Using a leak detection solution or soap suds, check
for leaks at pressure boss screw. Bubbles forming
indicate a leak. SHUT OFF GAS AND FIX ALL
LEAKS IMMEDIATELY.
NOTE: For gas to gas conversion, consult your dealer for
appropriate conversion.
Gas Line
Gas
Shutoff
Valve
Drip Leg Cap
With Fitting
Manometer Hose
Measuring Inlet Gas Pressure
Alternate Method
Gas Line
To Furnace
Open To
Atmosphere
Manometer
Manifold Gas Pressure
Gas
Natural
Low Stage
High Stage
Propane
Low Stage
High Stage
Manifold Gas Pressure
Gas BTU Input (Natural Gas Only) Check
To measure the gas input use a gas meter and proceed as
follows:
1. Turn off gas supply to all other appliances except the
unit.
2. With the unit operating, time the smallest dial on the
meter for one complete revolution. If this is a 2 cubic
foot dial, divide the seconds by 2; if it is a 1 cubic foot
dial, use the seconds as is. This gives the seconds
per cubic foot of gas being delivered to the unit.
3. INPUT=GAS HTG VALUE x 3600 / SEC. PER
CUBIC FOOT
Example: Natural gas with a heating value of 1000
BTU per cubic foot and 34 seconds per cubic foot as
determined by Step 2, then:
Input = 1000 x 3600 / 34 = 106,000 BTU per Hour.
NOTE: BTU content of the gas should be obtained
from the gas supplier. This measured input must not
be greater than shown on the unit rating plate.
4. Relight all other appliances turned off in step 1. Be
sure all pilot burners are operating.
Main Burner Flame Check
Flames should be stable, soft and blue (dust may cause
orange tips but they must not be yellow) and extending
directly outward from the burner without curling, floating or
lifting off.
Temperature Rise Check
Check the temperature rise through the unit by placing
thermometers in supply and return air registers as close
to the unit as possible. Thermometers must not be able to
sample temperature directly from the unit heat exchangers,
or false readings could be obtained.
1. All registers must be open; all duct dampers must be
in their final (fully or partially open) position and the
unit operated for 15 minutes before taking readings.
2. The temperature rise must be within the range
specified on the rating plate
16
Range
Nominal
1.6 -2.2" W.C.
2.0" W.C.
3.2 - 3.8" W.C.
3.5" W.C.
5.7 - 6.3" W.C.
6.0" W.C.
9.7 - 10.3" W.C.
10.0" W.C.
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