Instruction manual

32
M
P
1
3
2
C
O
F
F
ON
Outlet (Manifold)
Pressure Tap
(Side of Valve)
Pressure Re
g
ulator
Adjustment
(Under Cap Screw)
OUTLET
INLET
Inlet Pressure Tap
(Side of Valve)
Gas Valve
On/Off
Selector
Switch
zzz
White-Rodgers Model 36E22 or 36E23
Gas Line
Gas Shutoff Valve
Gas Line
To Furnace
Drip Leg Cap
With Fitting
Manometer Hose
Manometer
Open To
Atmosphere
Measuring Inlet Gas Pressure
(Alternate Method)
3. Turn ON the gas supply and operate the furnace and
all other gas consuming appliances on the same gas
supply line.
4. Measure furnace gas supply pressure with burners
firing. Supply pressure must be within the range
specified in the table below.
Propane Gas
Natural Gas
Inlet Gas Supply Pressure
Minimum:5.0" W.C. Maximum :10.0" W.C.
Minimum:11.0" W.C. Maximum :13.0" W.C.
If supply pressure differs from above, make necessary
adjustments to pressure regulator, gas piping size, etc.,
and/or consult with local gas utility.
5. Turn OFF gas to furnace at the manual shutoff valve
and disconnect manometer. Reinstall plug before
turning on gas to furnace.
6. Turn OFF any unnecessary gas appliances started in
step 3.
GAS MANIFOLD PRESSURE MEASUREMENT AND
ADJUSTMENT
CAUTION
To prevent unreliable operation or
equipment damage, the gas manifold
pressure must be as specified on the unit
rating plate. Only minor adjustments
should be made by adjusting the gas valve
pressure regulator.
Only small variations in gas pressure should be made by
adjusting the gas valve pressure regulator. The manifold
pressure must be measured with the burners operating.
To measure and adjust the manifold pressure, use the
following procedure.
1. Turn OFF gas to furnace at the manual gas shutoff
valve external to the furnace.
2. Connect a calibrated water manometer (or appropri-
ate gas pressure gauge) at the gas valve outlet pres-
sure tap (refer to gas valve figure in previous section).
3. Turn ON the gas supply and operate the furnace.
4. Measure gas manifold pressure with burners firing.
Adjust manifold pressure using the table below.
Manifold Gas Pressure
Natural Gas 3.5" w.c.
Propane Gas 10.0" w.c.
The final manifold pressure must not vary more
than ± 0.3 “ w.c. from the above specified pressures. Any
necessary major changes in gas flow rate should be made
by changing the size of the burner orifice.
5. To adjust the gas valve pressure regulator, remove the
regulator cap.
6. Turn the adjustment screw clockwise to increase the
pressure, or counterclockwise to decrease the pres-
sure.
7. Securely replace the regulator cap.
8. Turn OFF gas to furnace at the manual shutoff valve
and disconnect manometer.
9. Reinstall gas valve outlet pressure tap plug before
turning on gas to furnace.
GAS INPUT RATE MEASUREMENT (NATURAL GAS
ONLY)
The gas input rate to the furnace must never be greater
than that specified on the unit rating plate. To measure
natural gas input using the gas meter, use the following
procedure.
1. Turn OFF the gas supply to all other gas-burning
appliances except the furnace.
2. While the furnace is operating, time and record one
complete revolution of the smallest gas meter dial.
3. Calculate the number of seconds per cubic foot (sec/