24
WARNING:
Do not attempt to drill the gas orifi ces. Use
only factory supplied orifices. Improperly
drilled orifi ces may cause fi re, explosion,
carbon monoxide poisoning, personal injury
or death.
a.) Obtain the manifold pressure setting required for
this installation by referring to Table 10 for Propane
or Tables 12 or 13 for Natural Gas (pages 36-37).
b.) Remove the regulator capscrew (Figure 21) from
the INLET side of the regulator.
c.) Slowly turn the adjustment screw inside the regulator
to obtain the appropriate manifold pressure.
IMPORTANT NOTE: Turning the screw clockwise
increases the pressure and turning the screw
counter-clockwise decreases the pressure. To
prevent backing the screw all the way out from
the valve, turn the screw slowly.
d.) Replace and tighten the regulator capscrew over
the adjustment screw.
NOTE:
Lowering the blower speed will increase the
temperature rise and a higher blower speed will decrease
the temperature rise.
The furnace is equipped with a multi-speed motor. Heating
and cooling speed selection is made by moving the switch
on the integrated control located in the furnace.
Verifying Burner Operation
CAUTION:
The door over the burners may only be open
for inspection purposes only. The door must be
installed during unattended operation.
1. Remove the burner compartment door.
2. Set the thermostat above room temperature and
observe the ignition sequence.
NOTE:
The burner
fl ame should carry over immediately between all
burners without lifting off, curling, or fl oating. The
fl ames should be blue, without yellow tips.
3. After validating the fl ame, change thermostat setting
to below room temperature.
4. Verify the burner fl ame is completely extinguished.
5. Replace the burner compartment door.
Verifying Operation of the Supply Air Limit Switch
Note:
A properly functioning limit switch should turn off
the gas valve when the return is blocked (time depends
on how well the return air is blocked). The circulating air
and combustion blowers should continue to run when the
limit switch opens
.
1. Verify the blower door is securely mounted in place
and that there is power to the furnace.
2. Block the return airfl ow to the furnace by installing
a close-off plate in place of or upstream of the
fi lter(s).
3. Set the thermostat above room temperature and
observe the Operating Sequence (page 25).
4. Remove the close-off immediately after the limit
switch opens. If the furnace continues to operate
with no return air, set the thermostat below room
temperature, shut off the power to the furnace, and
replace the limit switch.
Capscrew
Figure 21. Regulator Capscrew
Verifying and Adjusting Temperature Rise
Confi rm the temperature rise through the furnace is
within the limits specifi ed on the furnace rating plate. Any
temperature rise outside the specifi ed limits could result
in premature failure of the heat exchanger.
1.
Place thermometers in the return and supply air stream
as close to the furnace as possible. The thermometer
on the supply air side must be shielded from direct
radiation from the heat exchanger to avoid false
readings.
2. Adjust all registers and duct dampers to the desired
position and run the furnace for 10 to 15 minutes before
taking any temperature readings. The temperature
rise is the difference between the supply and return
air temperatures.
For typical duct systems, the temperature rise will fall
within the limits specifi ed on the rating plate with the blower
speed at the factory recommended setting. If the measured
temperature rise is outside the specifi ed limits, it may be
necessary to change the speed of the blower.
