ICP G9MAE0601714A Service And Technical Support Manual page 7

SERVICE AND TECHNICAL SUPPORT MANUAL
2. Remove the 1/8 inch NPT plug from the outlet pressure
tap on the gas valve.
3. Connect a manometer to the outlet pressure tap on gas
valve.
4. Turn on furnace power supply.
5. Turn gas supply manual shutoff valve to ON position.
6. Turn furnace gas valve switch to ON position.
7. Jumper the R to W/W1 and W2 thermostat connections
at the furnace control board.
8. After the main burners ignite and the blower starts,
confirm Maximum Heat manifold pressure is correct,
based on the manifold pressure tables in the installation
instructions.
9. To adjust the Maximum Heat manifold pressure, slowly
turn adjusting screw counterclockwise to decrease
manifold pressure or clockwise to increase manifold
pressure. Turn adjustment no more than one click per
second until you obtain the required manifold pressure.
10. Main burner flame should be clear blue, almost
transparent.
11. After adjusting the Maximum Heat manifold pressure,
remove jumpers across thermostat connections to
terminate the call for heat.
12. Wait for blower off-delay to finish then reset 115-v power
to furnace.
Adjust Manifold Pressure−Minimum Heat
To adjust manifold pressure to obtain input rate for Minimum
Heat:
1. Turn SW1−2 ON at the furnace control. Set up switch
SW4−2 must be OFF.
2. Jumper R and W/W1 thermostat connections on control
to start furnace.
3. After the main burners ignite and the blower starts,
confirm Minimum Heat manifold pressure is correct,
based on the manifold pressure tables in the installation
instructions.
4. To adjust the Minimum Heat manifold pressure, slowly
turn adjusting screw counterclockwise (out) to decrease
manifold pressure or clockwise (in) to increase manifold
pressure. Turn adjustment no more than one click per
second until you obtain the required manifold pressure.
5. After adjusting the manifold pressure, remove jumpers
across thermostat connections to terminate the call for
heat. Wait until the blower off delay is completed.
6. Move setup switch SW1-2 to the OFF position.
7. Turn gas supply manual shutoff valve to OFF position.
8. Turn off furnace power supply.
WARNING
!
FIRE HAZARD
Failure to follow this warning could result in personal injury,
death, and/or property damage.
Re−install manifold pressure tap plug in gas valve to
prevent gas leak.
9. Remove manometer from the inlet pressure tap of the
gas valve.
10. Apply pipe dope sparingly to end of inlet gas pipe plug
and re-install in the gas valve.
440 04 4700 00
11. Re-install cap over adjustment screw on the top of the
gas valve.
Clocking the Meter
Verify natural gas input rate by clocking meter.
NOTE: Contact your HVAC distributor or gas supplier for metric
gas meter Tables, if required.
1. Turn off all other gas appliances and pilots served by the
meter.
2. Move setup switches SW1-2 to ON position and SW4-2
to OFF. This keeps furnace locked in Minimum Heat
operation when only W/W1 is energized or Maximum
Heat operation when R to W/W1 and W2 are jumpered.
3. Jumper R to W/W1 and W2. Run furnace for 3 minutes in
Maximum Heat operation.
4. Measure time (in sec) for gas meter to complete one
revolution and note reading. The 2 or 5 cubic feet dial
provides a more accurate measurement of gas flow.
5. Refer to Table 3 for cubic ft. of gas per hr. Multiply gas
rate cu ft./hr by heating value (Btuh/cu ft.) to obtain input
rate.
6. If clocked rate does not match required input from Step
5, increase manifold pressure to increase input or
decrease manifold pressure to decrease input. Repeat
steps 3 through 5 until correct maximum heat input is
achieved.
7. Remove jumpers across thermostat connections to
terminate the call for heat. Wait until the blower off delay
is completed then reset 115-v power to furnace.
8. Jumper R and W/W1 thermostat connections on control
to start furnace.
NOTE: Setup switches SW1-2 must be ON and SW4-2 must
be OFF. This keeps furnace locked in minimum heat operation
when R to W/W1 is energized. Repeat items 3 through 6 for
minimum heat operation until minimum heat input is achieved
9. Restore furnace to normal operating condition.
10. Remove jumpers
terminate the call for heat. Wait until the blower off delay
is completed.
11. Disconnect 115 VAC power to furnace.
12. Turn gas valve ON/OFF switch to OFF.
13. Remove water column manometer or similar device from
manifold pressure tap (if still connected).
FIRE HAZARD
Failure to follow this warning could result in personal injury,
death, and/or property damage.
Re−install manifold pressure tap plug in gas valve to
prevent gas leak.
14. Replace manifold pressure tap plug to gas valve.
15. Turn gas valve ON/OFF switch to ON.
16. Move setup SW1-2 on furnace control to position
required for attached thermostat (OFF for single-stage
thermostats, ON for two-stage thermostats).
17. Check for gas leaks and verify furnace operation.
Specifications subject to change without notice.
Gas Furnace: (F/G)9MAE
across thermostat connections to
WARNING
!
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