StyleCrest Installation Manual

11
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 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. See Figure 20 (page 16) for typical
thermostat connections.
Humidifier
The unit has an output to power a humidifier when the
blower is running during a call for heat. This output is
rated to 1.0 amp at 208/240V.
Dehumidification Options
The motor control board has a DHUM or D connection
(violet wire) that allows the system to increase the amount
of humidity that is removed from the circulating air. See
Figure 21 (page 17) This is accomplished by reducing
the CFM and allowing the cooling coil to become colder.
This will only occur when there is a call for cooling. There
are many ways that this can be electrically wired.
1. If the room thermostat incorporates a humidity sensor
and DHUM output, connect the DHUM on the thermostat
to the D terminal on the motor control board. See Figure
21
.
2. If using a separate humidistat, connect the DHUM & R
terminals on the humidistat to the D & R terminals on
the motor control board of the air handler. In this option,
the DHUM output of the humidistat must be set so it is
only closed when there is a call for dehumidification.
3. If a humidistat is not available, it is an acceptable
option to connect the R & D terminals on the motor
control board together with a field supplied wire. This
option causes the blower to run at a reduced CFM for
10 minutes after a call for cooling. NOTE: If outdoor
unit is a heat pump, connect the O terminal to the D
terminal.
Electronic Air Cleaner (EAC)
The unit has an output to power an electronic air cleaner
when the blower is running. This output is rated to 1.0
amp at 208/240V. See
Figure 21 (page 17).
Changing Blower Speed
NOTE TO INSTALLER
When the unit is installed, the heating and cooling
speeds must be set for that particular installation.
The installer is responsible for setting these speeds.
Blower speed is determined by the DIP switch settings
located on the unit control board. Pins 1-4 set the speed
for heating. Pins 5-8 set the speed for cooling/heat pump.
Refer to Table 6 (page 16) for allowable heating speeds.
See Table 4 (page 15) and Table 5 (page 15) for blower
performance data.
Installing Control Circuit Wiring
NOTE: Installation of at least a four-wire thermostat circuit
is required with five-wire circuit recommended for future
addition of a heat/cool thermostat. Any unused thermostat
leads must be properly capped. See Figure 20 (page 16)
for various thermostat connections.
1. Install the 24V control-circuit cable through plastic
bushing at either side of furnace.
2. Route control circuit wiring to wall thermostat and outdoor
section, if installed.
START-UP & ADJUSTMENTS
Pre-Start Check List
√ Verify the polarity of the connections are correct,
the line voltage power leads are securely connected
and the furnace is properly grounded. Refer to the
appropriate wiring diagram.
√ Verify the thermostat wires are securely connected
to the correct leads on the terminal strip of the circuit
board.
√ Check blower motor connectors for proper connection.
Start-up Procedures
1. Reinstall control box cover(s).
2. Switch circuit breaker(s) to the ON position.
3. Replace outer furnace door.
4. Check all duct connections and tape for air leakage.
Table 3. FSHE Motor Control Board Display Codes
DISPLAY
CODE
CURRENT MODE
- -
Standby is a Rotating Segment
C
C
Cooling Mode (Y input active)
H H
Heating Mode (W input active)
f
f
Circulate Fan Mode (G input active)
d
d
Dehum Cooling Mode (DEHUM input active along with Y)
I I
(one) A Motor Fault has Occurred (BMF active for more
than 30 seconds)
t
t
(lower case t) Over Temperatures (The value of the TS
input has exceeded 80C all outputs are stopped.)
L
L
Lockout (Ten (10) or more Motor Faults or Over
Temperature events have occurred. All outputs are set to off
for one hour.
NOTE: Display code may be inverted depending on final installation
orientation.