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HEAT PUMP HEATING MODE—TWO-SPEED LOW
Thermostat closes R to Y1. The Y1 signal is sent directly to ICM2.
HEAT PUMP HEATING WITH AUXILIARY ELECTRIC
HEAT
Thermostat closes circuits R to Y/Y2 and/or R to Y1 with R to W2,
W3, or E (and R to O in the case of defrost).
See previously described modes for circuit paths.
In the event that electric heating is called for by thermostat while
heat pump is also operating in either heating or defrost mode,
electric heating signal will appear at motor connector pin 1 as
described previously. If necessary, the motor will modify its
airflow output to provide an airflow which is defined as safe for
operation of electric heater.
CFM SELECT CONFIGURATION TAPS
The CFM Select taps are used by installer to configure system. The
ICM2 is capable of discerning wave shapes on some of its inputs
and uses this capability to modify its operation to a pre-
programmed table of airflows and can be modified in response to
other inputs such as the need for de-humidification.
ICM2 CONTROL POWER
The ICM2 control power is supplied from R circuit through
printed-circuit runs to motor control connector pin 6, through
motor control harness to motor. The C side of low-voltage control
power circuit is connected by printed-circuit runs to motor
connector pins 4 and 5, then through motor control harness to
motor.
LOW-VOLTAGE CIRCUIT FUSING AND REFERENCE
The low-voltage circuit is fused by a board-mounted 5-amp
automotive-type fuse placed in series with transformer SEC2 and
R circuit. The C circuit of transformer is referenced to chassis
ground through a printed-circuit run at SEC1 connected to metal
standoff marked GROUND SCREW REQUIRED.
NOTE:
A ground screw must be in place or erratic motor
operation can result.
TRANSFORMER, MOTOR, AND ELECTRIC HEATER
POWER CONNECTIONS
The high-voltage (230-vac) power input to board is provided
through electric heater connector pins 7 and 9. The high voltage is
then connected through printed-circuit runs to motor power con-
nections M1 and M2 and transformer power connections T1 and
T3. Transformer connection T2 is a dummy terminal used for
unused primary power lead. The transformer secondary connec-
tions are made at SEC1 and SEC2 connectors.
Step 4—Easy Select Configuration Taps
The Easy Select taps are used by installer to configure system. The
ICM2 uses selected taps to modify its operation to a pre-
programmed table of airflows. Airflows are based on system size
or mode of operation and those airflows are modified in response
to other inputs such as the need for de-humidification.
(See Fig. 16.)
The FK4B Fan Coil must be configured to operate properly with
system components with which it is installed. To successfully
configure a basic system (see information printed on circuit board
located next to select pins), move the 5 select wires to pins which
match components used.
Fig. 16—Easy Select Board
A94076
EASY SELECT
GROUND
SCREW
REQUIRED
L
R
C
O
Y/Y2
Y1
G
E
CES0130007–00
D8 D7 D5
D6
P1
D1
D2
D9
D4
R2
HEATER
240
VAC
T2
T3
M2
M1
T1
XFORM
MOTOR
240
VAC
SEC2
SEC1
24VAC
D3
P2
R3
JW3
JW4
AUX2
AUX1
HUM1
HUM2
24VDC
JW1
JW2
D11
R1
CESS430023–01
CEBD430023–01
D10
FS1
5 AMP
MAX
ST1
RED
MOTOR
AMP 12-PIN MATE-N-LOCK
CONNECTOR (1)
3
⁄
16
-IN. MALE
FASTON
AMP–TYP
(21) PLCS
MOLEX 7-PIN
CONNECTOR (1)
LOW VOLTAGE
TERMINAL BLOCK
W2-E JUMPER
3RD STAGE
W2
W3
W2-W3 JUMPER
2ND STAGE
PRINTED
CIRCUIT
BOARD
1
⁄
4
-IN. MALE
FASTON
AMP–TYP
(9) PLCS
AUX
HEAT
RANGE
AC/HP
SIZE
TYPE
AC/HP
CFM
ADJUST
DELAY
AC/HP TIME
ENH
VIO
ORN
BLK
GRY
BLU
ON
OFF
0
90
30
90
0
0
HI
MED
LO
HP-EFF
HP-COMFORT
AC
KW
CFM
0-30
1200
0-20
1000
0-10
800
0-5
600
042
036
030
024
5
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