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Main Burner Gas Orifice
1. To remove the main burner gas orifice shut off the main
power and gas supply to the furnace.
2. Remove the top door and inlet air orifice. The orifice is
located inside the assembly and can be taken out for
verification and cleaning. Refer to the
for size.
3. Replace the main burner air orifice in reverse order they
were removed.
Air Inlet Orifice
The combustion air inlet is a specified size and cannot be
left off or changed to an alternate size. The inlet air orifices
are unique between models. Interchanging, modifying or
removing the air orifice plates will result in unsafe operation
and erratic behavior. Refer to
air orifice size. Only use factory size main air orifices. Refer
to the RPL for replacement parts.
ELECTRICAL WIRING
WARNING:
ELECTRICAL SHOCK, FIRE OR
EXPLOSION HAZARD
Failure to follow safety warnings exactly could
result in serious injury, death or property
damage.
Improper servicing could result in dangerous
operation, serious injury, death or property
damage.
• Before servicing, disconnect all electrical
power to furnace.
• When servicing controls, label all wires prior
to disconnecting. Reconnect wires correctly.
• Verify proper operation after servicing.
• Electrical connections must be in compliance with all
applicable local codes with the current revision of the
National Electric Code (ANSI/NFPA 70).
IMPORTANT NOTE:
If replacing any of the original wires supplied with the
furnace, the replacement wire must be copper wiring and
have a temperature rating of at least 105° F (40° C). For
electrical specifications, refer to the furnace nameplate
Line Voltage Wiring
It is required that the line voltage (120 VAC) to the furnace
be supplied from a dedicated branch circuit containing the
correct fuse or circuit breaker for the furnace as listed in
The installer should become familiar with the units wiring
diagram before making any electrical connections to the
, or
the unit wiring label.
IMPORTANT NOTES:
An electrical disconnect must be installed readily
accessible from and located within sight of the furnace.
See
or
wiring diagram label inside of the control door. Any
other wiring methods must be acceptable to authority
having jurisdiction.
Proper line voltage polarity must be maintained in order
for the control system to operate correctly. Verify the
incoming neutral line is connected to the white wire
and the incoming HOT line is connected to the black
wire. The furnace will not operate unless the polarity
and ground are properly connected as shown in
.
Grounding
WARNING:
To minimize personal injury, the furnace cabinet
must have an uninterrupted or unbroken electrical
ground. The controls used in this furnace require
an earth ground to operate properly. Acceptable
methods include electrical wire or conduit
approved for ground service. Do not use gas
piping as an electrical ground!
Thermostat / Low Voltage Connections
• The furnace is designed to be controlled by a 24 VAC
thermostat. The thermostat’s wiring must comply with the
current provisions of the NEC (ANSI/NFPA 70) and with
applicable local codes having jurisdiction.
• The thermostat must be installed according to the
instructions supplied by the thermostat manufacturer.
Low voltage connections (24 VAC) from the thermostat
are wired to the terminal strip on the integrated control
connections for heating only (two-wire) and heating/
cooling (four-wire) applications. Recommended minimum
wire gauge for thermostat wiring is shown in
• The thermostat should be mounted about 5 feet above
the floor on an inside wall. DO NOT install the thermostat
on an outside wall or any other location where its
operation may be adversely affected by radiant heat from
fireplaces, sunlight, or lighting fixtures, and convective
heat from warm air registers or electrical appliances.
Refer to the thermostat manufacturer’s instruction sheet
for detailed mounting information.
Twinning
Single stage funaces are not supplied with a built-in twinning
capability.
