GMES96-U Installation Manual

28
OUTLET
INLET
Regulator Cover
Screw
White-Rodgers Model 36J22Y-204
Connected to Manometer
Figure 33
NOTE: If measuring gas pressure at the drip leg, a field-supplied
hose barb fitting must be installed prior to making the hose
connection. If using the inlet pressure tap on the White-Rodgers
36J22 gas valve, then use the 36G/J Valve Pressure Check Kit,
Part No. 0151K00000S.
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
Inlet Gas Supply Pressure table 5, on page 22.
If supply pressure differs from table, make the necessary adjust-
ments 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 and tighten as
needed before turning on gas to furnace.
6. Turn OFF any unnecessary gas appliances stated in step 3.
Gas Line
Gas
Shutoff
Valve
Gas Line
To Furnace
Drip Leg Cap
With Fitting
Manometer Hose
Manometer
Open To
Atmosphere
Measuring Inlet Gas Pressure (Alt. Method)
Figure 34
GAS MANIFOLD PRESSURE MEASUREMENT AND ADJUSTMENT
Only small variations in gas pressure should be made by adjust-
ing 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. Turn off all electrical power to the system.
3. Outlet pressure tap connections:
White-Rodgers 36J22 valve: Back outlet pressure test screw
(outlet pressure tap) out one turn (counterclockwise, not
more than one turn).
4. Connect calibrated U tube manometer (or appropriate
pressure gauge) at the gas valve outlet pressure tap.
See White-Rodgers 36J22Y-204 gas valve Figure 33 for
location of outlet pressure tap.
5. Turn ON the gas supply.
6. Turn on power and close thermostat “R” and “W” contacts
to provide a call for heat.
7. Measure the gas manifold pressure with burners firing.
Adjust manifold pressure using the Manifold Gas Pressure
table 9 shown below.
Gas Range Nominal
Natural 2.8 - 3.2" w.c. 3.0" w.c.
Manifold Gas Pressure
Table 9
8. Remove regulator cover screw from the outlet pressure
regulator adjust tower and turn screw clockwise to increase
pressure or counterclockwise to decrease pressure. Replace
regulator cover screw.
9. Turn off all electrical power and gas supply to the system.
10. Remove the manometer hose from the hose barb fitting
or outlet pressure tap.
11. Replace outlet pressure tap: White-Rodgers 36J22 valve:
Turn outlet pressure test screw in to seal pressure port
(clockwise, 7 in-lb minimum).
12. Turn on electrical power and gas supply to the system.
13. Close thermostat contacts “R” and “W” to energize the
valve.
Using a leak detection solution or soap suds, check for leaks
at outlet or screw (White-Rodgers valve). Bubbles forming
indicate a leak. SHUT OFF GAS AND REPAIR ALL LEAKS IM-
MEDIATELY!
CAUTION
T O PREVENT UNRELIABLE OPERATION OR EQUIPMENT DAMAGE , THE
INLET GAS SUPPLY PRESSURE MUST BE AS SPECIFIED ON THE UNIT
RATING PLATE WITH ALL OTHER HOUSEHOLD GAS FIRED APPLIANCES
OPERATING .