16
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:
a. White-Rodgers Valve:
Back outlet pressure test screw (outlet pressure
Tap) out one turn (counterclockwise, not more than
one turn).
4. Connect manometer (or appropriate pressure gauge)
at the gas valve outlet pressure tap. See White-
Rodgers 36J22Y-204 gas valve 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. Using a leak detection solution or soap suds, check
for leaks at outlet pressure tap screw (White-Rodgers
valve). Bubbles forming indicate a leak. SHUT OFF
GAS AND REPAIR ALL LEAKS IMMEDIATELY!
8.
Measure the gas manifold pressure with burners firing.
Adjust manifold pressure using the following
Manifold
Gas Pressure
table.
Mode
.
White-Rodgers Model 36J22 Connected to Manometer
Natural Gas
2.8" - 3.2" w.c.
Manifold Gas Pressure
The Manifold Gas Pressure must be within the range
specified.
9. Remove regulator cover screw from the outlet
pressure regulator and turn screw clockwise to
increase pressure or counterclockwise to decrease
pressure. Replace regulator cover screw.
10. Turn OFF all electrical power and gas supply to the
system.
11. Remove the manometer hose from the hose barb
fitting or outlet pressure tap.
12. Replace outlet pressure tap:
a. White-Rodgers Valve:
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. Close thermostat contacts to provide a call for heat.
16. Retest for leaks. If bubbles form, SHUT OFF GAS
AND REPAIR ALL LEAKS IMMEDIATELY!
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 36 seconds per cubic foot as
determined by
Step 2, then:
Input = 1000 x 3600 / 36 = 100,000 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.
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.
