Tempstar A Series, Installation, Start-Up, Operating, Service And Maintenance Instructions

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F96CTN and G96CTN (Series A): Installation, Start-up, Operating, Service and Maintenance Instructions
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
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24-V WIRING
Make field 24-v connections at the 24-v terminal strip. See Fig. 38 .
Connect terminal Y/Y2 as shown in Fig. 36 for proper cooling operation.
Use only AWG No. 18, color-coded, copper thermostat wire.
NOTE: Use AWG No. 18 color-coded copper thermostat wire for
lengths up to 100 ft. (31 M). For wire lengths over 100 ft., use AWG No.
16 wire.
The 24-v circuit contains an automotive-type, 3-amp. fuse located on the
control. Any direct shorts during installation, service, or maintenance
could cause this fuse to blow. If fuse replacement is required, use ONLY
a 3-amp. fuse of identical size. See Fig. 38 .
Thermostats
A single stage heating thermostat can be used with the furnace. The
furnace control board CPU will control the furnace staging. A two stage
heating and cooling thermostat can also be used to control the staging.
For two stage thermostat control of the furnace staging, turn SW1-2 ON
at the furnace control board. A two stage cooling thermostat must be
used to control a 2-stage outdoor unit, remove. Refer to typical
thermostat wiring diagrams and the Sequence of Operation section for
additional details. Consult the thermostat installation instructions for
specific information about configuring the thermostat. See Fig. 38 and
Fig. 39 .
A single stage heating and cooling thermostat can be used with the
furnace. The furnace control board CPU will control the furnace and
outdoor unit staging. A two stage heating and cooling thermostat can
also be used to control the staging. For two stage thermostat control of
the furnace staging, turn SW1-2 ON at the furnace control board. For
two stage thermostat control of a 2-stage outdoor unit, remove the
ACRDJ jumper from the furnace control board. Refer to typical
thermostat wiring diagrams and the Sequence of Operation section for
additional details. Consult the thermostat installation instructions for
specific information about configuring the thermostat. See Fig. 38 and
Fig. 39 .
Accessories
(See Fig. 38 and Fig. 37 .)
1. Electronic Air Cleaner (EAC)
Connect an accessory Electronic Air Cleaner (if used) using 1/4-in.
female quick connect terminals to the two male 1/4-in.
quick-connect terminals on the control board marked EAC-1 and
EAC-2. The terminals are rated for 115VAC, 1.0 amps maximum
and are energized during blower motor operation.
2. Humidifier (HUM)
The HUM terminal is a 24 VAC output, energized when the blower is
operating during a call for heat.
Connect an accessory 24 VAC, 0.5 amp. maximum humidifier (if used)
to the ¼ -in. male quick-connect HUM terminal and COM-24V screw
terminal on the control board thermostat strip.
NOTE: If the humidifier has its own 24 VAC power supply, an isolation
relay may be required. Connect the 24 VAC coil of the isolation relay to
the HUM and COM/24V screw terminal on the control board thermostat
strip. See Fig. 37 .
3. Communication Connector (communication connection)
This connection is used when the furnace is controlled by an
optional communicating User Interface instead of a standard
thermostat. The communication plug is supplied with the User
Interface. Refer to the instructions supplied with the User Interface
for complete details. See Fig. 38 .
4. Outside Air Thermistor (OAT)
The OAT connection is used in conjunction with communicating
User Interface. It is not required when the furnace is controlled by a
standard type thermostat. Refer to the instructions supplied with the
User Interface for complete details.
Communication Connector is used when the furnace is controlled by an
optimum communicating User Interface. See Fig. 35 .
The communication plug is supplied with the User Interface. Refer to the
instructions supplied with the User Interface.
A03193I
Fig. 35 – Communication Connector
Outside Air Thermistor (OAT)
Used in conjunction with communicating User Interface. Not required
when a standard type thermostat is used. Refer to the instructions
supplied with the User Interface for details.
Alternate Power Supplies
This furnace is designed to operate on utility generated power which has
a smooth sinusoidal waveform. If the furnace is to be operated on a
generator or other alternate power supply, the alternate power supply
must produce a smooth sinusoidal waveform for compatibility with the
furnace electronics. The alternate power supply must generate the same
voltage, phase, and frequency (Hz) as shown in Table 10 or the furnace
rating plate.
Power from an alternate power supply that
is non-sinusoidal may
damage the furnace electronics or cause erratic operation.
Contact the alternate power supply manufacturer for specifications and
details.
A11401
Fig. 36 – Typical Two-Stage Field Wiring Diagram
WARNING
!
FIRE, EXPLOSION, ELECTRICAL SHOCK, AND
CARBON MONOXIDE POISONING HAZARD
Failure to follow this warning could result in dangerous operation,
personal injury, death, or property damage.
Do not drill into blower shelf of furnace to route control wiring. Route
any control or accessory wiring to the blower compartment through
external knockouts on the casing.
DX+ DX-
R C
W/W1
W2
COM
Y/Y2
R
G