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Automatic Heat Staging Jumper
Figure 33
The furnace must be grounded and wired in accordance
with local codes or, in the absence of local codes, with the
National Electrical Code ANSI/NFPA No. 70 (latest edition)
and/or CSA C22.1 Electrical Code (latest edition) if an
external electrical source is utilized.
In all instances, other than wiring for thermostat, the wiring
to be done and any replacement of wire shall conform with
the temperature limitation for Type T wire – 63°F (35°C) rise.
Connect a sufficiently sized wire with ground to the furnace’s
line voltage connections and ground lug. Refer to the
furnace rating plate for electrical characteristics to be used
in sizing field supply wiring and over-current protection.
The line voltage supply should be routed through a readily
accessible disconnect located within sight of the furnace.
A junction box on the furnace side panel is provided for
line voltage connections. Refer to the furnace wiring
diagram for specific connection information.
Proper polarity of the supply connections (“HOT”
and “NEUTRAL”) must be observed to ensure that
safety controls provide the protection intended.
A connection to the ground lug and actual earth ground
(typically a ground stake or buried steel pipe) must be
maintained for proper operation.
Thermostat
Install a room thermostat according to the instructions
furnished with it. Select a location on an inside wall that is
not subject to drafts, direct sunshine, or other heat
sources. The initial heat anticipator setting should be
equal to the total current draw of the control circuit.
Low voltage thermostat connections are to be made to the
integrated ignition/blower control board as indicated on the
wiring diagram.
Single Stage Thermostat Operation
The automatic heat staging option allows a single stage
thermostat to be used with a two stage G2D93CT/U or
G2D95CT/U furnace. To activate this option, move the
jumper pin (see Figure 33) to desired setting (5 minutes or
10 minutes). The furnace will start on 1
st
stage heat and
Electrical Wiring
Risk of electrical shock. Disconnect electrical
power at the circuit breaker or service panel
before making electrical connections. Failure
to disconnect power supplies can result in
property damage, personal injury, or death.
WARNING
stay at 1
st
stage heat for the duration of the selected time
before switching to 2
nd
stage heat.
W1 on the control board must be connected to W1 on the
thermostat.
Humidifier
Terminals are provided on the integrated ignition/blower
control board for connection to a 120-volt humidifier. The
“HUM” terminal is energized whenever the thermostat calls
for heat. Refer to furnace wiring diagram for specific
connection information.
Electronic Air Cleaner
Terminals are provided on the integrated ignition/blower
control board for connection of a 120-volt electronic air
cleaner. The “EAC” terminal is energized whenever the
thermostat calls for heat, cooling, or continuous blower.
Refer to the furnace wiring diagram for specific connection
information.
Continuous Blower Operation (G2D93CT/U Models)
The comfort level of the living space can be enhanced when
using this feature by allowing continuous circulation of air
between calls for cooling or heating.
If continuous blower operation on low speed is desired,
connect the lowest speed motor tap to the “CONT”
terminal on the integrated ignition/blower control board
(refer to the furnace wiring diagram.) The blower will
operate on low speed whenever main power is connected
to the furnace, except when it operates on heating or
cooling speed during thermostat call for heat or cooling.
This constant air terminal is intended for low speed
only.
If a motor is wired for a higher speed, the increased
amp draw could cause the board control to fail and void
the warranty.
