Page 50
31-5000724 Rev. 0
4.
This furnace is equipped with an ignition device which
automatically lights the burners. Do not try to light the
burners by hand.
5.
Remove the upper access panel.
6.
Move gas valve switch to OFF. See Figure 45.
7.
Wait five minutes to clear out any gas. If you then
smell gas,
STOP
! Immediately call your gas supplier
from a neighbor’s phone. Follow the gas supplier’s
instructions. If you do not smell gas go to next step.
8.
Move gas valve switch to ON. See Figure 45.
9.
Replace the upper access panel.
10.
Turn on all electrical power to to the unit.
11.
Set the thermostat to desired setting.
NOTE:
When unit is initially started, steps 1 through
11 may need to be repeated to purge air from gas line.
12.
If the appliance will not operate, follow the instructions
“Turning Off Gas to Unit” and call your service
technician or gas supplier.
Turning Off Gas to Unit
1.
Set the thermostat to the lowest setting.
2.
Turn off all electrical power to the unit if service is to
be performed.
3.
Remove the upper access panel.
4.
Move gas valve switch to OFF.
5.
Replace the upper access panel.
Failure to Operate
If the unit fails to operate, check the following:
1.
Is the thermostat calling for heat?
2.
Are access panels securely in place?
3.
Is the main disconnect switch closed?
4.
Is there a blown fuse or tripped breaker?
5.
Is the filter dirty or plugged? Dirty or plugged filters will
cause the limit control to shut the unit off.
6.
Is gas turned on at the meter?
7.
Is the manual main shut-off valve open?
8.
Is the internal manual shut-off valve open?
9.
Is the unit ignition system in lockout? If the unit locks
out again, inspect the unit for blockages.
10.
Is blower harness connected to integrated control?
Furnace will not operate unless harness is connected.
Safety or Emergency Shutdown
Turn off unit power. Close manual and main gas valves.
Extended Period Shutdown
Turn off thermostat or set to “UNOCCUPIED” mode.
Close all gas valves (both internal and external to unit)
to guarantee no gas leak into combustion chamber. Turn
Heating System Service Checks
CSA Certification
All units are CSA design certified without modifications.
Refer to the NF97DM Installation Instruction.
Gas Piping
If a flexible gas connector is required or allowed by
the authority that has jurisdiction, black iron pipe shall
be installed at the gas valve and extend outside the
furnace cabinet.
CAUTION
Do not over torque (800 in-lbs) or under torque (350
in-lbs) when attaching the gas piping to the gas valve.
WARNING
Gas supply piping should not allow more than 0.5”W.C.
drop in pressure between gas meter and unit. Supply gas
pipe must not be smaller than unit gas connection.
Compounds used on gas piping threaded joints should be
resistant to action of liquefied petroleum gases.
Testing Gas Piping
In case emergency shutdown is required, turn off the
main shut-off valve and disconnect the main power to
unit. These controls should be properly labeled by the
installer.
IMPORTANT
When pressure testing gas lines, the gas valve must be
disconnected and isolated. Gas valves can be damaged if
subjected to more than 0.5psig (14” W.C.). See Figure 46.
MANUAL MAIN SHUT-OFF
VALVE WILL NOT HOLD
NORMAL TEST PRESSURE
CAP
FURNACE
ISOLATE
GAS VALVE
1/8” N.P.T. PLUGGED TAP
Figure 46.
off power to unit. All access panels and covers must be in
place and secured.