Carrier KSAIC0301230 User manual

Specifications subject to change without notice.
Read and become familiar with these instructions before beginning
installation.
SAFETY CONSIDERATIONS
Read these instructions thoroughly and follow all warnings or cautions
included in the literature and attached to the unit. Consult local building codes
and National Electrical Code (NEC) for special requirements. Recognize
safety information.
This is the safety-alert symbol . When you see this symbol on the unit and
in instructions or manuals, be alert to the potential for personal injury.
Understand these signal words: DANGER, WARNING, and CAUTION.
These words are used with the safety-alert symbol. DANGER identifies the
most serious hazards which will result in severe personal injury or death.
WARNING signifies hazards which could result in personal injury or death.
CAUTION is used to identify unsafe practices which may result in minor
personal injury or product and property damage. NOTE is used to highlight
suggestions which will result in enhanced installation, reliability, or operation.
TABLE OF CONTENTS
PAGE
SAFETY CONSIDERATIONS........................................................1
OVERVIEW .....................................................................................1
DIMENSIONS..................................................................................2
CLEARANCES ................................................................................2
INSTALLATION .............................................................................3
SYSTEM CONFIGURATION SCENARIOS .................................3
WIRING ...........................................................................................8
DIP SWITCHES CONFIGURATION.............................................11
WIRING DIAGRAM .......................................................................13
APPENDIX 1 - COMPATIBILITY CHART...................................14
APPENDIX 2 - PIPING ADAPTER BUSHINGS/REDUCERS.....15
APPENDIX 3 - FV4C TRANSFORMER........................................15
APPENDIX 4 - ADDITIONAL REFRIGERANT CHARGE FOR
CONVENTIONAL FAN COILS .....................................................15
APPENDIX 5 - FV4C AIRFLOW DELIVERY ..............................16
OVERVIEW
The 24V INTERFACE KIT is used to connect:
A Single or Multi-zone Ductless System to a 3rd party single stage
conventional thermostat.
A Single Zone Ductless Condensing Unit 38MA*R with an approved
Fan Coil. For other applications, consult your Ductless representative.
Fig. 1 —24V Interface
NOTES: Images are for illustration purposes only. Actual models may be
slightly different.
Table 1 —Kit Contents: Confirm the following parts are included
Table 2 — Field Supplied Components: Prepare the following assemblies on site
ELECTRICAL SHOCK HAZARD
Failure to follow this warning could result in personal injury or death.
Before beginning any modification or installation of this kit, be sure
the main electrical disconnect is in the OFF position.
Ensure power is disconnected to the fan coil unit. On some systems
both the fan coil and the outdoor unit may be on the same disconnect.
Tag the disconnect switch with a suitable warning label. There may
be more than one disconnect.
WARNING
EQUIPMENT DAMAGE HAZARD
Failure to follow this warning may result in equipment damage.
Do not install the wired controller in an area subjected to excessive
steam, oil or sulfide gas. Doing so may cause the controller to deform
and/or fail.
CAUTION
INSTALLATION
Entrust the distributor or authorized professionals to install the unit.
Installation by unskilled persons may lead to improper installation,
electric shock, or fire. Re-installation must be performed by
authorized professionals. Non-compliance may lead to electric shock
or fire.
CAUTION
No. Description Qty Remarks
1 Control box 1 N/A
2 Installation Manual 1 N/A
3 Screws 3 M4X20 (for wall mounting)
4 Wall Anchors 3 For wall mounting
7
Return Air Thermistor Assembly
(Hybrid Solutions) (RCD part
number 11201007003448)
1
Required and installed near
or on the unit and on the air
inlet side
8
16ft. (5m) Return Air Thermistor
Assembly Extension Wires (RCD
part number 17401204010126)
1
For a Return Air
Temperature Sensor on
Hybrid Solutions
No. Description Qty Type Remarks
1 Switch Box 1 N/A N/A
2Wiring Tube (insulating sleeve
and tightening screw) 1 N/A N/A
KSAIC0301230 24V Interface Kit
for Ductless Systems and Hybrid Solutions
Installation Instructions

2 Specifications subject to change without notice. IM-KSAIC03-02
DIMENSIONS
Fig. 2 —24V Interface Structure Size
CLEARANCES
Table 3 — 24V Interface Clearance Dimensions
Fig. 3 —Clearances
The wiring should adapt to the wire control current.
Otherwise, electric leakage or overheating may occur and result in a
fire.
The specified cables shall be used in the wiring. No external force
may be applied to the terminal. Otherwise, the wire may be damaged
and heating may occur and result in a fire.
WARNING
The shielded wire must be grounded. Sensor connecting cable should
not be longer than 23ft. (7m). The control box operates on low
voltage circuit loops. DO NOT connect a 220V or 380V cable to the
circuit loop.
CAUTION
8.7”
(220mm)
1.3”
(32mm)
6.9”
(176mm)
0.6”
(15mm)
7.8”
(200mm)
11.1”
(283mm)
2.5”
(63mm)

Clearances
Unit Minimum Value In (mm)
Sides 5.9 (150)
Front 24 (610)*
Top and Bottom 3 (76.2)
>5.9 (150) >5.9 (150)

IM-KSAIC03-02 Specifications subject to change without notice. 3
INSTALLATION
Installation Location
The 24V INTERFACE KIT is rated for outdoor and indoor mounting
(depending on the application). It is recommended to install as close
as possible to the indoor unit and thermostat.
IMPORTANT: Follow the recommended clearances and
install in an area above the ground away from locations where
water could enter.
Fig. 4 —Installation Floor Mount View (right way)
Fig. 5 —Installation Floor Mount View (wrong way)
1. Remove the cover of the 24V INTERFACE KIT. Remove the six
screws of the 24V INTERFACE KIT with a screwdriver or
similar tool. Rotate the lid along the hem to disassemble.
Fig. 6 —Remove the cover
2. Mount the 24V INTERFACE KIT horizontally (see Fig. 7), by
fastening the back plate to the wall with 3 screws\ (M4x20) and
anchors.
Fig. 7 —24V Interface Kit
NOTE: Place the unit on a flat surface. Be careful not to
distort the back plate of the 24V INTERFACE KIT by over
tightening the screws.
3. WIRING - Based on the system used, wire the unit as shown in the
System Configuration Scenarios section.
4. Cover the 24V INTERFACE KIT lid, and lock back in place
using the six screws previously removed.
Fig. 8 —Cover the screw
System Configuration
NOTES:
• Thermostat should be configured for use with a conventional
system.
• The wireless remote controller, wired controller and Wi-Fi
cannot be used with this 24V interface Kit at the same time.
Only the Swing and LED function may be accessed with the
wireless remote.
Table 4 — Connection Wiring Specification
SYSTEM CONFIGURATION SCENARIOS
Follow the configuration scenarios for the right connections
depending on the system:
Scenario 1: Single Zone Ductless System with 38MPRA, 38MA*R,
38MHR
Scenario 2: Single Zone Ductless System with 38MBR
Scenario 3: Multi-zone Ductless System with 38MGR
Scenario 4: Single Zone Fan Coils FMA/FMC/FMU with 38MA*R
Scenario 5: Single Zone Fan Coils FV4C with 38MA*R
Right
Wrong
DO NOT install the 24V INTERFACE KIT near flammable liquids
or gases such as gasoline or hydrogen sulfide. Doing so creates a fire
hazard.
CAUTION

The 24V Interface kit cover has a directional arrow on the cover. In
case of outdoors installation verify, during the mounting process, that
this arrow will point UP upon installation. Failure to mount the kit
correctly can cause water ingress into the box which may compromise
the electrical component integrity.
CAUTION
Connection
Wiring
Outdoor
L1, L2, S & G,
S1, S2
Indoor
L1, L2, S & G,
S1, S2
R,C Y/W/G/G1/
G2/G3/Dry
Size
Refer to the
outdoor
connecting
wires size
Refer to the
indoor
connecting
wires size
18AWG
(minimum)
18AWG
(minimum)
Back plate
Screws (M4×20)

4 Specifications subject to change without notice. IM-KSAIC03-02
SYSTEM CONFIGURATION SCENARIOS
Scenario No. 1:
Match the following ductless indoor units with the corresponding
compatible SINGLE ZONE outdoor units:
• High Wall (sizes 9-36)[208-230V]
• Cassette (sizes 9-24)
• Ducted (sizes 9-24) (*refer to NOTE)
• Console (sizes 18-24)
Installation Steps:
1. Run the interconnecting piping from the indoor to the outdoor unit
using the indoor piping size.
2. Run the interconnecting wiring from the outdoor unit to the 24V
interface using terminal connections L1, L2, S and G.
3. Run the interconnecting wiring from the 24V interface to the indoor
unit using terminal connections L1, L2, S and G.
4. Run the thermostat wiring from the thermostat to the 24V interface
using connections R and C on CN15 and Y, W, G on CN19.
5. Configure the dip switches on the 24V interface accordingly.
NOTES:
Follow the Indoor and Outdoor unit's general installation
instructions.
*For the Ducted units, in order to initially setup the static
pressure, the 24V interface must be bridged. Temporarily connect
together the Communication wires L1, L2, S and G from indoor
to outdoor unit until static pressure settings are complete (see
ducted unit Installation Manual). When static pressure is
adjusted, reconnect L1, L2, S and G wires to the terminal blocks.
On selected indoor units, the Up-Down Swing Louver function as
well as the control to turn off the indoor unit display (LED) is
available on the unit’s Wireless Remote controller. The Wi-Fi
accessory and Wired Remote controller are not functional when
using the 24V interface.
For 115V Ductless applications the 24V transformer must be
replaced in the field. This is available through RCD part number
11203103000393.
Fig. 9 —Wiring Diagram
IMPORTANT: All ground wiring must be installed according to the equipment installation manual.
The indoor unit requires an updated control board for compatibility
with the 24V interface.
Refer to the Compatibility Charts on hvacpartners.com for proper
matches and serial number compatibility.
CAUTION
Thermostat
70
Do not
connect to
indoor sensor
Power supply from
outdoor unit disconnect.
Two wires are line voltage
and the other is a ground wire.
*All ground wiring must be installed
according to the equipment installation manual.
*All ground wiring must be installed
according to the equipment
installation manual.
G
BUS BAR
G
G
G
G

IM-KSAIC03-02 Specifications subject to change without notice. 5
Scenario No. 2:
Single Zone Outdoor units 38MBR with approved Ductless indoor
units Cassettes, Ducted and Consoles (for proper combinations
consult the compatibility chart).
• Cassette (sizes 36-48)
• Ducted (sizes 36-48) (*refer to NOTE)
• Console (sizes 36-48)
Installation Steps:
1. Run the interconnecting piping from the indoor to the outdoor using
the indoor piping size.
2. Run the interconnecting wiring from the outdoor unit to the 24V
interface using terminal connections L1, L2, and G. Connect the
wiring for the S1 & S2 outdoor interface to CN8.
3. Run the interconnecting wiring from the 24V interface to the indoor
unit using terminal connections L1, L2, and G. Connect the wiring
for S1 & S2 outdoor interface to CN9.
4. Run the thermostat wiring from the thermostat to the 24V interface
using connections R and C on CN15 and Y, W, G on CN19.
5. Configure the dip switches on the 24V interface accordingly.
NOTES:
Follow the Indoor and Outdoor unit's general installation
instructions.
*For Ducted units, in order to initially setup the static pressure,
the 24V interface must be bridged. Temporarily connect together
the Communication wires S1 and S2 from indoor to outdoor unit
until static pressure settings are complete (see ducted unit
Installation Manual). When static pressure is adjusted, connect S1
and S2 to CN8 and CN9 (see Fig. 21).
On selected indoor units, the Up-Down Swing Louver function as
well as the control to turn off the indoor unit display is available
on the unit’s Wireless Remote controller. The Wi-Fi accessory and
Wired Remote controller is not functional when using the 24V
interface.
Fig. 10 —Wiring Diagram
Do not
install
indoor sensor
Power supply
from outdoor
unit disconnect
Two wires are line
voltage and the
other is a ground wire.
BUS BAR
G
G
G
G

6 Specifications subject to change without notice. IM-KSAIC03-02
Scenario No. 3:
Multi-zone Outdoor units 38MGR with approved Ductless indoor
units High Walls, Cassettes, Ducted and Consoles. (For proper
combinations, consult the compatibility chart).
• High Wall (Sizes 9-24)
• Cassette (Sizes 9-24)
• Ducted (Sizes 9-24) (*refer to NOTE)
• Console (Sizes 9-24)
Installation Steps:
1. Run interconnecting piping from Indoor to Outdoor using Indoor
piping size.
2. Run interconnecting wiring from outdoor unit to 24V interface
using terminal connections L1, L2, S, and G.
3. Run interconnecting wiring from 24V interface to indoor unit using
terminal connections L1, L2, S and G.
4. Run thermostat wiring from thermostat to 24V interface using
connection R and C on CN15 and Y, W, G on CN19.
5. Configure the dip switches on the 24V interface accordingly.
NOTES:
One 24V interface and one thermostat is required per indoor unit
head. Follow the Indoor and Outdoor unit's general installation
instructions.
*For Ducted units, in order to initially setup the static pressure,
the 24V interface must be bridged. Temporarily connect together
the Communication wires L1, L2, S and G from indoor to outdoor
unit until static pressure settings are complete (see ducted unit
Installation Manual). When static pressure is adjusted, reconnect
L1, L2, S and G wires to the terminal blocks.
In the AUTO mode, the system automatically cools or heats the
room according to the user-selected set point. mode, the system
automatically cools or heats the room according to the user-
selected set point.
AUTO mode is recommended for use on Single Zone applications
only. Using AUTO changeover on multi-zone applications could
set an indoor unit to STANDBY mode, indicated with two dashes
(--) on the display, which will turn off the indoor unit until all the
indoor units are in the same mode (COOLING or HEATING).
HEATING is the system's priority mode. Simultaneous
HEATING and COOLING is not allowed.
On selected indoor units, the Up-Down Swing Louver function as
well as the control to turn off the indoor unit display, is available
on the unit’s wireless remote control. The Wi-Fi accessory and
wired remote control is not functional when using the 24V
interface.
Fig. 11 —Wiring Diagram
Thermostat
70
G
G
G
G
Do not
connect the
indoor sensor
Power supply from outdoor
unit disconnect.
Two wires are line voltage and
the other is a ground wire.
BUS BAR

IM-KSAIC03-02 Specifications subject to change without notice. 7
Scenario No. 4:
Single Zone outdoor unit 38MA*R with approved multi-family 24V
fan coils FMA/FMC/FMU. (For proper combinations consult the
compatibility chart in the “APPENDIX 1 - COMPATIBILITY
CHART” on page 14).
Installation Steps:
1. Remove TXV/Piston on the indoor unit.
2. Run interconnecting piping from outdoor to indoor using Outdoor
piping size and brazing to the adapter for the mechanical fitting
from which the TXV was removed (Part number 331831-701)
(available through RCD). If required, use the Bushing / Reducers
listed on “APPENDIX 2 - PIPING ADAPTER BUSHINGS/RE-
DUCERS” on page 15.
3. Suction and liquid refrigerant lines must be properly insulated and
separated from each other to prevent condensation and energy loss.
4. Disconnect and remove the 24V transformer from the 24V interface
kit. Run 2-conductor wire from 24 volt side of the Indoor Unit
transformer to CN16 and CN17.
5. Run interconnecting wiring from outdoor unit to 24V interface
using terminal connections L1, L2, S and G.
6. Run thermostat wiring from thermostat to 24V interface using
connection R and C on CN15 and Y, W, G on CN19.
7. Run thermostat wiring from 24V interface to indoor unit using
output connections G1 (Low), G1+G2 (Medium), G1+G2+G3
(High) on the 24V interface and connect according to the
installation manual for these fan coils.
8. Install the T1 sensor on CN5 on the 24V interface and place on the
return of the indoor unit.
9. Configure the dip switches on the 24V interface accordingly.
NOTES: Follow the Indoor and Outdoor unit's general
installation instructions.
The T1 (Return air temperature) sensor should be near or on the
unit and on the air inlet side. The thermistor should be installed
pointing down into the duct between 2.5ft. (0.762m) and 4ft.
(1.2m) from the return side of the fan coil. Use a 1/2” drill and
insert the thermistor no less than 6 in. into the duct and seal air
tight around cable.
Fig. 12 —Wiring Diagram for Conventional 24V Fan Coil indoor unit
When the outdoor unit is matched with a Multi-Family or Residential
Fan Coil and due the need to braze the piping on the fan coil side it is
REQUIRED to flow Nitrogen in the system while brazing the line set
since a filter drier is not recommended to be used with these
condensing units.
CAUTION
Thermostat
70
Transformer
L1
L2
G
GG
G
Red dash mea
n
disconnect
Power supply from outdoor unit disconnect.
Two wires are line voltage and the other is a
ground wire.
Power supply from indoor
unit disconnect
1 2 3 4 5
NGLC
BUS BAR

8 Specifications subject to change without notice. IM-KSAIC03-02
Scenario No. 4 (cont):
WIRING
All wires must be sized per NEC (National Electrical Code) or CEC
(Canadian Electrical Code) and local codes. Use Electrical Data table
MCA (minimum circuit amps) and MOCP (maximum over current
protection) to correctly size the wires and the disconnect fuse or
breakers respectively.
Per the caution note, only stranded copper conductors with a 600 volt
insulation rating wire must be used. Separate power supplies are
required for the OUTDOOR UNIT and the INDOOR UNIT.
The field supplied 14/3 stranded wire with ground and a 600 volt
insulation rating, power/communication wiring from the OUTDOOR
UNIT to 24V INTERFACE KIT consists of four (4) wires and
provides the power for the 24V Interface. Two wires are line voltage
AC power, one is communication wiring (S) and the other is a ground
wire. Wiring between the OUTDOOR UNIT to 24V INTERFACE
KIT is polarity sensitive. The use of B X wire is NOT recommended.
Auxiliary Heating: To energize an Auxiliary Heater, connect W2 on
the thermostat directly to the an electric heat relay(s) (field supplied)
and complete the circuit to the heater element(s).
The thermostat must be setup to use different heating priorities.
Key Considerations
The following steps should be taken when using this device with a
conventional central air conditioning unit:
• Indoor coil metering device (TXV/Piston) must be removed
• 24V transformer in the interface module must be disconnected
• Refrigerant charge amount may need to be adjusted, depending on
the pipe size and length, see the outdoor recharge instruction.
• The maximum air flow should not exceed 400 CFM/Ton.
When the indoor air handler or furnace has its own 24VAC
transformer, you must disconnect all four wires of the 24V Interface
kit transformer (see Fig. 13).
Fig. 13 —Wiring
Control Logic
Table 5 — Conventional Thermostat Connections
Table 6 — Mode Setting
FAN SPEED - Select Auto, Low Medium or High Airflow
For Ductless Systems (Scenarios 1-3) the Fan Speed defaults to
AUTO. For Hybrid Solutions, see “Scenario No. 4:” on page 7. The
fan outputs are G1 (1st), G1+G2 (2nd), and G1+G2+G3 (3rd). For
the single fan speed only, G1 has to be connected.
Use the selection options provided to adjust the airflow supplied to
meet the individual installation needs for such things as noise,
comfort, and humidity removal.
Table 7 — Fan Speed Setting
LEGEND
The conventional thermostat must be configured for use
with a single stage air conditioner (Y output ONLY) and a
single stage heating (W) system.
CAUTION
Connector Purpose
R/C 24VAC Output
Y Cooling
W Heating
G Fan
AUX/DRY Aux/Dry Mode
Y W G Aux/Dry Setting Mode
X☆ ☆ Cooling
X☆X Heating
X X X
Fan only
  ☆ ☆ OFF
X X X X OFF
X X ☆DRY Mode (on Ductless Systems)
Unit ON/OFF G Setting Fan Speed
X Auto Fan Speed
  Auto Fan Speed
X X Fan OFF
ON
XOFF
☆ON or OFF
Only the approved combinations and model numbers of the fan coils
listed on the Appendix shall be used to avoid any damages to the fan
motor.
The use of a fan coils with a PSC motor is not recommended or
approved.
CAUTION

IM-KSAIC03-02 Specifications subject to change without notice. 9
Scenario No. 5:
Single Zone outdoor unit 38MA*R with approved residential 24V fan
coils. (For proper combinations consult the compatibility chart in
“APPENDIX 1” on page 14).
Installation Steps:
1. Remove TXV on the indoor unit.
2. Run interconnecting piping from outdoor to indoor using Outdoor
piping size and brazing to the mechanical fitting adapter that
replaces the TXV (part number 331831-701) (available through
RCD). If required, use the Bushing / Reducers listed on
“APPENDIX 2 - PIPING ADAPTER BUSHINGS/REDUCERS”
on page 15.
3. Suction and liquid refrigerant lines must be properly insulated and
separated from each other to prevent condensation and energy loss
4. Disconnect and remove the 24 volt transformer from the 24 Volt
Interface. Run 2-conductor 18 AWG cable from R and C of the
indoor unit terminal board. Connect “R” to CN17 and “C” to CN16
on the 24 Volt Interface. Be sure to connect the primary (high
voltage) wire to the correct terminal (tap) on the FV4C transformer
(see Appendix 3).
5. Run interconnecting wiring (14-3 AWG stranded power cable with
ground and 600 volt insulation rating) from outdoor unit to 24 Volt
Interface using terminal connections L1, L2, S, and G. Connect
ground wire G to the grounding connection in the case.
6. Run 18 AWG thermostat wiring from thermostat terminals to the 24
Volt Interface and connect to R and C on CN15. Also connect Y, W,
and G on CN19. NOTE: Use an instrument size flat blade
screwdriver with a maximum blade width of 1/8” for the screw
terminals.
7. Run 18 AWG thermostat wiring from “G1” on CN18 of the 24 Volt
Interface to “G” on the indoor unit terminal board.
8. Install the T1 sensor (included with 24 Volt Interface) on CN5 of
the 24 Volt Interface and locate according to the NOTE, below.
9. Configure the dip switches on the 24 Volt Interface for proper
operation:
For Heat Pump – all switches OFF except SW1-1 = ON
For Cooling Only – all switches OFF except SW1-1 = ON and
SW2-1 = ON.
10. Configure the Fan Coil "Easy Select" Printed-Circuit Board
following the instructions on the installation manual of the indoor
unit.
NOTES: Follow the Indoor and Outdoor unit’s general
installation instructions.
The T1 (Return Air Temperature) sensor should be near or on the
indoor unit on the air inlet side. The thermistor should be
installed pointing down into the duct between 2.5 ft (0.75 m) and 4
ft (1.2 m) from the return side of the fan coil. Use a ½” drill and
insert the thermistor no less than 6 in (15 cm) into the duct and
seal air tight around the cable.
Fig. 14 —Wiring Diagram for FV4C Fan Coil Unit
When the outdoor unit is matched with a Multi-Family or Residential
Fan Coil and due the need to braze the piping on the fan coil side it is
REQUIRED to flow Nitrogen in the system while brazing the line set
since a filter drier is not recommended to be used with these
condensing units.
CAUTION
Thermostat
70
G
GG
G
FV4C
Indoor Unit
L1
L2
24V
D
H
R
W
1
W
2
Y
1
YY
1
G
O C
Red dash mean
disconnect
Power supply from outdoor unit disconnect.
Two wires are line voltage and the other is a
ground wire.
Power supply from indoor
unit disconnect
BUS BAR

10 Specifications subject to change without notice. IM-KSAIC03-02
Basic Setup for the FV4C “EASY SELECT” Printed-Circuit Board
BASIC FAN COIL CONFIGURATION
The following basic configuration of the fan coil will provide AHRI rated performance of the heat pump:
A. AUX HEAT KW/CFM −
Select the heater range for the size electric heater installed.
B. AC/HP SIZE −
Select system size installed.
For size 12K select 018 on the board
For sizes 18 - 36 select the nominal connector on the board.
C. SYSTEM TYPE -
Select system type
D. AC/HP CFM ADJUST −
Select NOM.
E. ON/OFF DELAY −
Select 0/90 profile.
F. CONTINUOUS FAN −
Select desired fan speed when thermostat is set to
continuous fan.
For size 12K select 'MED"
TXV Replacement Process for Piping Adapter
For FV4CNF002L00 and FV4CN(B,F)003L (Refer to Fig. 15)
1. Gain access to the Built-in TXV inside the Fan Coil Cabinet.
2. Double-wrench the TXV mechanical connector and disassemble.
3. Cut the bleed line from the TXV to the suction line and braze closed the capillary tube.
4. Remove the tail bulb from the suction line by cutting the stainless steel band.
5. Assemble the line set to the Piping adapter kit (331831-701 obtain through RCD).
a. Use 3/8" copper sweat long radius street elbow and 3/8" copper sweat coupling (field supplied).
b. Field fabricate 3/8" copper tubing by cutting 3 3/4" length.
c. Temporarily remove the Teflon gasket from the tip of the piping adapter.
d. Make sure that the brass nut is properly positioned on the adapter before brazing.
e. Flow Nitrogen for brazing.
f. Braze the street elbow, tubing and coupling (See Figure 16) to complete the piping adapter.
g. Refer to Appendix 2 for Bushing/Reducer sizing.
h. Adapt (where needed) and braze the liquid line to the piping adapter.
i. Alternate for steps "A", "B", and "F: Use a tubing bender to bend the end of the 3/8" liquid line, cut the tip so that the bend length is 1
3/4" from the outer edge of the tubing (See Figure 17).
6. Place Teflon gasket on the brass tip of the Piping Adapter and insert into the aluminum distributor head.
7. Thread piping adapter brass nut onto the distributor line and tighten - finger tight + 1/2 turn.
Fig. 18 —Detail of FV4C Printed-Circuit Board
Fig. 15 —Piping Adapter Replacement
Fig. 16 —Braze Street Elbow,
Tubing, and Coupling
Fig. 17 —Bend Liquid Line

IM-KSAIC03-02 Specifications subject to change without notice. 11
DIP SWITCHES CONFIGURATION
The 24V INTERFACE KIT must be configured to operate properly
with the system components with which it is installed. To successfully
configure the system, move the Dip Switches to match the
components and functions used.
NOTE: Properly identify the DIP switch number marked
on the board of the 24V interface as SW1 through SW4
before selecting the options. On each DIP switch block the
numbers 1 and 2 would be marked.
Fig. 19 —DIP Switch Definitions
DIP Switch 1-1
Used to turn ON or OFF the diagnostic code display LED on the
control board of the 24V Interface (see Fig. 20).
Table 8 — DIP Switch 1-1
Fig. 20 —LED
DIP Switch 1-2
Used for selection of the indoor unit type.
Table 9 — DIP Switch 1-2
NOTES*:
1. Need to remove the indoor unit throttle (piston/TXV/ orifice);
2. Indoor fan will stop during defrost and will start again 30
seconds after the defrost cycle is complete on the outdoor unit.
G1, G2 and G3 on the 24V interface will not provide any fan
output signal to the Indoor Fan during the defrost cycle plus 30
seconds.
NOTE: If this 24V interface is matched with Non-Ductless
indoor unit, the DIP switch must be set to OFF.
DIP Switch 2-1
Used for selection of the system: Cooling Only or Heat Pump.
Table 10 — DIP Switch 2-1
DIP Switch 2-2
Used for freeze protection of the indoor coil (only available on
Scenarios 1 through 3).
Table 11 — DIP Switch 2-2
NOTE: Applicable only to Ductless Style Indoor Heat
Pump units in Heating Mode.
DIP Switch 3-1
On Ductless Systems, Dry is used with thermostats with a Dry
Function output.
Table 12 — DIP Switch 3-1
DIP Switch 3-2
Used to increase the compressor frequency in case the set point has
not been reached after 1 hour or 3 hours of operation. The unit will
keep operating as Variable Speed on both cases.
Table 13 — DIP Switch 3-2
DIP Switch 4-1
Not required. Used on future applications. Select the indoor unit’s fan
only mode.
Table 14 — DIP Switch 4-1
DIP Switch 4-2
Not required. Used on future applications. Select the indoor unit’s fan
speed (when selecting DIP switch 4-1).
Table 15 — DIP Switch 4-2
NOTE: If the SW4-1 is ON, the SW4-2 takes effect, otherwise the
SW1-2 takes effect.
SW1-1 Result Note
ON Display on
OFF Display off Default
SW1-2 Result Note
ON Sets - Both Ductless Indoor and Outdoor Units
(For Scenarios 1-3)
OFF
Outdoor only (Hybrid Solution) (For Scenario 4)
----- Compatible with other 24V indoor units Fan
Coil/Furnace/Cased Coil.
Default
(see
NOTES*
below)
SW2-1 Result Note
ON Cooling Only
OFF Heat Pump Default
SW2-2 Result Note
ON Fan does not stop
OFF Fan will stop if the indoor coil temperature is low Default
SW3-1 Result Note
ON Dry Mode
OFF Used on future applications Default
SW3-2 Result Note
ON 1h
OFF 3h Default
SW4-1 Result Note
ON The SW4-2 is available under fan only mode
OFF The SW1-2 is available Default
SW4-2 Result Note
ON Medium fan speed
OFF High fan speed Default

12 Specifications subject to change without notice. IM-KSAIC03-02
ERROR CODES
For ease of service, the 24V Interface is equipped with a diagnostic code display LED on the control board (ensure the 24V interface is installed
with the directional arrow pointing up to successfully read the error code). Refer to the indoor or outdoor unit’s service manual as listed in
Table 16 for a troubleshooting breakdown.
Table 16 — Error Codes
Display Malfunction and Protection Indication Service Manual Reference
E0 Indoor EEPROM error Indoor Service Manual
E2 Cross-zero detection error Indoor or Outdoor Service Manual
E3 Indoor fan speed malfunction Indoor Service Manual
E4 Indoor room temperature sensor error Indoor Service Manual
E5 Evaporator coil temperature sensor error Indoor Service Manual
EC Refrigerant leak detection system malfunction Indoor or Outdoor Service Manual
F0 Current overload protection Outdoor Service Manual
F1 Outdoor ambient temperature sensor (T4) malfunction Outdoor Service Manual
F2 Condenser coil temperature sensor (T3) malfunction Outdoor Service Manual
F3 Condenser coil temperature sensor (T5) malfunction Outdoor Service Manual
F4 Outdoor unit EEPROM parameter error Outdoor Service Manual
F5 Outdoor fan speed has been out of control Outdoor Service Manual
F6 T2b sensor error Indoor or Outdoor Service Manual
P0 Inverter module (IPM) malfunction Outdoor Service Manual
P1 Over-voltage or under-voltage protection Outdoor Service Manual
P2 Compressor top high temperature protection (OLP) Outdoor Service Manual
P3 Low ambient temperature cut off in heating Outdoor Service Manual
P4 Compressor drive malfunction Outdoor Service Manual
-- Mode conflict Indoor Service Manual
P6 Compressor low-pressure protection Outdoor Service Manual
IN 24V Interface and indoor unit communication malfunction Indoor Service Manual (E1)
0U 24V Interface (indoor unit) and outdoor unit communication malfunction Indoor Service Manual (E1)
00 24V Interface successful power up and in standby Operational Code
01 System operating in cooling mode Operational Code
02 System operating in heating mode Operational Code
03 System operating in fan mode Operational Code
04 System operating in dehumidify mode (not a recommended application for
FV4C units) Operational Code
05 System operating with Auxiliary heater active (not a recommended application) Operational Code

IM-KSAIC03-02 Specifications subject to change without notice. 13
WIRING DIAGRAM
Fig. 21 —Wiring Diagram
GLOSSARY:
• Remote Control (CN14): This is a dry contact to control the indoor unit on and off remotely.
• Alarm Output (CN7): This is a dry contact that opens and closes based on the alarm status of the system. This is a normally
closed Dry contact.
• Work Output (CN6): This contact is a dry contact that open and closes based on the system running or not running
condition.When the compressor is active this contact closes.
FAN OUTPUTS:
• (G1) Low Fan Speed
•(G1 + G2) Medium Fan Speed
• (G1+ G2 + G3) High Fan Speed
For single fan speed only, G1 has to be connected.
ON ON
NOTE: If the SW4-1 is ON, the SW4-2 takes
effect, otherwise the SW1-2 takes effect.
Dry Mode
Fan Low/Medium/High

14 Specifications subject to change without notice. IM-KSAIC03-02
APPENDIX 1 - COMPATIBILITY CHART
The 24V INTERFACE KIT is compatible with most thermostats matched with the Fan Coils listed in Tables 17, 18, and 19. Before installation,
check the compatibility of your Outdoor and Indoor Fan Coil. Professional installation is recommended.
Select Proper Blower Speed For the Fan Coil
Before operating unit, ensure that the proper blower speed has been selected. Fan speeds are selected manually. Refer to the installation manual
of the indoor unit for instructions on how to change the fan speed and select the taps (see Tables 17, 18, and 19) for the proper matches.
24V Interface Fan Speed Wiring (See Page 9 for Wiring Connections)
G3 is the High Fan Speed terminal and should be connected to the High tap speed inputs at the fan coil.
G2 is the Medium Fan Speed terminal and should be connected to the Medium tap speed inputs at the fan coil.
Tap G1 is Low Fan Speed terminal and should be connected to the Low tap speed inputs at the fan coil. The 24V interface may be connected to
a low Tap Speed, based on the installation instructions of the indoor unit.
Table 17 — Compatibility with FMA4 Fan Coils
Table 18 — Compatibility with FMC4 Cased Horizontal Fan Coils
Table 19 — Compatibility with FMU4 Uncased Horizontal Fan Coils
Table 20 — Compatibility with FV4 Fan Coils
Indoor Volt-
Ph@60Hz Kit Number Nominal System Size MBTUH
Indoor Model
Number
Outdoor Model
Number
Recommended Maximum
Indoor Fan
Speed Tap Number
FMA4
Vertical
Fan Coil
208/230-1 KSAIC0301230
12 FMA4X1800AL 38MAQB12R--3 Tap 1
18 FMA4X1800AL 38MAQB18R--3 Tap 2
24 FMA4X2400AL 38MAQB24R--3 Tap 5
30 FMA4X3000AL 38MAQB30R--3 Tap 2
36 FMA4X3000AL 38MAQB36R--3 Tap 4
Indoor Volt-
Ph@60Hz Kit Number Nominal System Size MBTUH
Indoor Model
Number
Outdoor Model
Number
Recommended Maximum
Indoor Fan
Speed Tap Number
FMC4
Cased
Horizontal
Fan Coil
208/230-1 KSAIC0301230
12 FMC4Z1800AL1 38MAQB12R--3 Low (Black)
18 FMC4Z1800AL1 38MAQB18R--3 Medium low (Blue)
24 FMC4Z2400AL1 38MAQB24R--3 Medium low (Blue)
30 FMC4Z3000AL1 38MAQB30R--3 Medium high (White)
36 FMC4Z3600AL1 38MAQB36R--3 Medium high (White)
Indoor Volt-
Ph@60Hz Kit Number Nominal System Size MBTUH
Indoor Model
Number
Outdoor Model
Number
Recommended Maximum
Indoor Fan
Speed Tap Number
FMU4
Uncased
Horizontal
Fan Coil
208/230-1 KSAIC0301230
12 FMU4Z1800AL1 38MAQB12R--3 Low (Black)
18 FMU4Z1800AL1 38MAQB18R--3 Medium low (Blue)
24 FMU4Z2400AL1 38MAQB24R--3 Medium low (Blue)
30 FMU4Z3000AL1 38MAQB30R--3 Medium high (White)
36 FMU4Z3600AL1 38MAQB36R--3 Medium high (White)
Indoor Volt-
Ph@60Hz Kit Number Nominal System Size MBTUH
Indoor Model
Number
Outdoor Model
Number
Recommended Fan Speed
Wiring and Configuration
FV4
Fan Coil 208/230-1 KSAIC0301230
12 FV4CNF002L00 38MAQB12R--3 Connect G1 on the 24V
interface to G on the fan coil.
Under the configuration taps
for AC/HP CFM ADJUST, the
recommendation is to
select NOM. Refer to Page
10 and Appendix 5 for setup.
18 FV4CNF002L00 38MAQB18R--3
24 FV4CNF002L00 38MAQB24R--3
30 FV4CN(B,F)003L 38MAQB30R--3
36 FV4CN(B,F)003L 38MAQB36R--3

IM-KSAIC03-02 Specifications subject to change without notice. 15
APPENDIX 2 - PIPING ADAPTER BUSHINGS/REDUCERS
A piping adapter kit 331831-701 (sold through RDC) is necessary when removing the factory supplied TXV on the indoor unit.
APPENDIX 3 - FV4C TRANSFORMER
This transformer is factory wired for 230V AC operation. For 208V AC applications, disconnect the black wire from the 230-v terminal on the
transformer primary side and connect it to the 208V terminal (See Fig. 22).
Fig. 22 —Transformer Connections on FV4C Fan Coils
APPENDIX 4 - ADDITIONAL REFRIGERANT CHARGE FOR CONVENTIONAL
FAN COILS
When matching the FMA4 and FMC/FMU indoor units, the size 12 units require 12.4 oz. (350 g) more refrigerant due to the size of the indoor
coil.
No refrigerant addition is necessary for the FV4 (any size).
All the outdoor units are shipped from the factory pre-charged for 25ft of piping length. See installation instructions of the outdoor unit for
additional charge requirements on longer piping lengths.
Model Size Bushings/Reducers Required (Field Supplied)
FMA
FMC
12-18 3/4” - 1/2” Suction only
3/8” - 1/4” Liquid
24-36 3/4” - 5/8” Suction only
3/8” - 1/4” Liquid
FMU
FV4
12-18 3/8” - 1/4” Liquid and 3/4” - 1/2” Suction
24-36 3/4” - 5/8” Suction only

Copyright 2019 CAC/BDP D 3300 Riverwood Parkway Atlanta GA, 30339 Edition Date: 08/19 Catalog No. IM-KSAIC03-02
Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations. Replaces: IM-KSAIC03-01
APPENDIX 5 - FV4C AIRFLOW DELIVERY
Table 21 — FV4C Fan Coil Airflow Delivery (CFM) in Heat Pump Only Heating Mode
NOTES:
1. The above airflows result with the AC, HP CFM ADJUST select jumper set on NOM.
2. Air flow can be adjusted +15% or -10% by selecting HI or LO respectively for all modes except fan only.
3. Dry coil at 230 volts and with 10KW heater and filter installed.
4. Airflows shown are at standard air conditions.
OPERATING MODE
UNIT SIZE OUTDOOR UNIT CAPACITY SINGLE SPEED APPLICATION FAN ONLY
HEAT PUMP EFFICIENCY LO MED HIGH
002
012
018
024
525
525
700
350
350
350
380
380
505
470
470
630
003 030
036
875
1050
415
470
630
755
785
945