Installation Manual

20
Converting to LP/Propane Gas at Altitudes
between 0 & 10,000 FT.
WARNING:
The furnace was shipped from the factory
equipped to operate on natural gas. Conversion
to LP / Propane gas must be performed by
qualified service personnel using a factory
supplied conversion kit. Failure to use the proper
conversion kit can cause fire, explosion, property
damage, carbon monoxide poisoning, personal
injury, or death.
Converting single stage valves to LP/Propane requires
the replacement of the burner orifices and flipping the
regulator cap to the side marked LP. The end facing up
should now read LP. See Figure 19.
Installation Example
Elevation: .................................................. 5,000 feet
Type of Gas: ........................................... Natural Gas
Local Heating Value of Gas: .............................. 750
From Table 10, find 750 and follow down the column,
stop at the 5,000 feet row. The heating value listed is
LOW. Table 12 will be used to determine orifice size
and manifold pressure.
After changing the orifices, it is required that you measure
the gas input rate. This may be accomplished in the usual
way, by clocking the gas meter and using the local gas
heating value. See Verifying & Adjusting the Input Rate
section (page 24).
IMPORTANT NOTE:
Observe the action of the burners to make sure there
is no yellowing, lifting or flashback of the flame.
WARNING:
Shut off the gas supply at the manual gas shutoff
valve, before disconnecting the electrical power.
A fire or explosion may result causing property
damage, personal injury or loss of life. Failure to
follow the safety warnings exactly could result in
serious injury, death or property damage.
WARNING:
To avoid electric shock, personal injury, or death,
turn off the electric power at the disconnect or the
main service panel before making any electrical
connections.
WARNING:
The reduction of input rating necessary for high
altitude installation may only be accomplished
with factory supplied orifices. Do not attempt to
drill out orifices in the field. Improperly drilled
orifices may cause fire, explosion, carbon
monoxide poisoning, personal injury or death.
Removing The Burner Orifices
1. Set the thermostat to the OFF position, or its lowest
temperature setting.
2. Shut OFF the gas supply at the manual shutoff valve
located outside of the appliance.
3. Turn off all electrical power to the appliance.
4. Remove the door from the burner box by removing 6
screws.
5. Turn the gas valve ON/OFF knob to the OFF position.
See Figure 19.
6. Remove the wires from the terminals of the gas valve.
7. Remove the supply gas piping from the gas valve inlet.
8. Carefully remove four screws securing the gas manifold
assembly to the burner assembly. See Figure 20.
9. Set the screws aside and remove the gas manifold
assembly from the appliance.
10. Carefully remove the burner orifices from the gas
manifold assembly.
Inlet
Pressure
Ta p
Manifold
Pressure Ta p
On / Off Knob
Te rminal
Connectors
N
A
T
N
A
T
L
P
L
P
OR
OTHER SIDE
OF CAP
Regulator Cap
Figure 19. Gas Valve
Figure 20. Orifice Removal
Bur
ner Box
Orifice
(X4)
Gas Valve
Gas Manifold
Burner Box
Door
(X4)
(X6)