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CRANKCASE HEATER OPERATION
The two-speed control board energizes the crankcase heater during
unit’s off cycle.
OUTDOOR FAN MOTOR OPERATION
The two-speed control energizes outdoor fan any time compressor
is operating. The outdoor fan remains energized during the
1-minute compressor speed change time delay and if a pressure
switch or compressor overload should open. Outdoor fan motor
will continue to operate for one minute after the compressor shuts
off when the outdoor ambient is greater than 100°F.
After termination of a defrost cycle, the outdoor fan delays coming
on for 20 sec. This allows refrigerant system to recover outdoor
coil heat and minimize the “steam cloud” effect.
DEFROST TIME SELECTION
The defrost interval can be field selected, dependent on local or
geographical requirements. It is factory set at 90 minutes but can
be changed to either 30, 60, or 120 minutes. To select defrost time,
set dip switches located on the left side of the unit board (See Fig.
14). See Table 5 for Defrost Dip Switch Settings.
DEFROST
The dual capacity control logic for defrost function is time and
temperature initiated, time or temperature terminated.
Defrost only occurs at outdoor temperatures less than 50°F. The
control initiates defrost when outdoor coil thermistor is 30°F (±2°)
or less, and selected defrost time (interval) has been accumulated
WIRING DIAGRAM NOTES:
1. Wiring must conform to NEC or local codes.
2. Underlined letter on thermostat terminal indicates its usage. For example: O/W2 means O is energized in cooling mode.
3. Refer to indoor unit Installation Instructions for any additional features and wiring information.
4. Non-Programmable Model 2S01–B, when used in heat pump installations (jumper R19 NOT cut), uses O/W2 to control reversing valve.
5. Furnace must control its own second-stage operation via furnace control algorithms. Refer to furnace Installation Instructions for proper
setup.
6. To activate dehumidify function on FK4, FV4, or 40FK, remove J1 jumper at fan coil control board.
7. Heat pump MUST have a high-pressure switch for dual fuel applications.
8. Outdoor air temperature sensor must be attached in all dual fuel applications.
9. Thermidistat Dip Switch No. 1 should be set in ON position for heat pump installations.
10. Thermidistat Dip Switch No. 2 should be set in the ON position for dual capacity compressor operation.
11. Thermidistat Configuration Option No. 10 “Dual Fuel Selection” must be turned ON in all dual fuel applications.
12. To activate dehumidify feature on current style 58UHV, 58UXV variable-speed 80-percent noncondensing furnaces, disconnect green
(dehum) wire from G on furnace control board and connect to dehumidify terminal DHUM on Thermidistat.
13. Dual Fuel Dip Switch–D (no. 4) must be set in the ON position for dual capacity compressor operation.
14. The DE jumper located next to the DHUM terminal must be removed to enable the DEHUM input.
A01222
LEGEND
24 VOLT FACTORY WIRING
24 VOLT FIELD WIRING
FIELD SPLICE CONNECTION
RELAY SPDT, PILOT DUTY
24-V COIL (HN61KK324)
OR EQUIVALENT
HUMIDISTAT, OPENS ON
HUMIDITY RISE (HL38MG026)
AIRFLOW SELECTOR
R1
H
AFS
Fig. 13—Typical Solenoid Valve Wiring
A01191
40FK
FK4/FV4
FAN COIL
TWO-SPEED
HEAT PUMP
24 VAC HOT
24 VAC COM
FAN
COOL/HEAT
STAGE 2
HEAT STAGE 3
RVS COOLING
N/A
OUTDOOR
SENSOR
CONNECTION
COOL/HEAT
STAGE 1
J2 JUMPER
J1 JUMPER
R
C
G
Y/Y2
W/W2
O/W2
Y1
B
S1
S2
DH
R
G
C
Y/Y2
W1
W2
O
Y1
R
C
Y2
W1
O
Y1
Y1
Y2
Y2
Y1
LLS
11