Mitsubishi Electric PAC-US444CN-1 Quick guide

© 2015 Mitsubishi Electric US, Inc. 1
•Onlyadealerorqualiedtechnician
shouldinstall,relocate,reinstall,or
repairthedevice.
Improper installation or repair may
result in electrical shock or re.
•Properlyinstallthedeviceona
stable,load-bearingsurface.
Device installed on an unstable
surface may fall and cause injury.
Contents
1. Supplied Parts.......................................................................................................1
2. Safety Precautions.................................................................................................1
3. System Conguration............................................................................................3
4. How to Install.........................................................................................................5
5. Usage....................................................................................................................8
1. ConrmingtheSuppliedParts
Check that the box includes the following part(s) in addition to this
installation manual:
PAC-US444CN-1 Thermostat Interface (1)
2. SafetyPrecautions
• Thoroughly read the following safety precautions before use.
• Hazards that can occur from incorrect handling are classied by the symbols below:
Warning Incorrect handling can result in death, serious injury, etc.
Caution Incorrect handling can result in bodily injury and/or
structure damage.
• After reading this manual, keep this manual for future reference. When the device
is reinstalled or repaired, give this manual to those who provide these services.
When the user changes, make sure that the new user receives this manual.
Warning
MANUFACTURED FOR:
MITSUBISHI ELECTRIC US, INC.
PAC-US444CN-1
INSTALLATION/INSTRUCTION MANUAL
Before using the device, carefully read this installation/instruction manual to ensure
proper operation.
Keep this manual for future reference and give it to the technician when the device
is reinstalled or repaired.
FORINSTALLER
Thermostat Interface
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© 2015 Mitsubishi Electric US, Inc. 2
•Onlyusethespeciedcables;
securelyconnecteachsothat
theterminalsdonotbearany
cableweight.
Improperly connected or short-circuited
cables may produce heat and cause
a re.
•Donotmakeanymodicationsor
alternationstothedevice.
Modications or improper repair may
result in electric shock or re. Consult
your dealer for repair.
•Allelectricalworkshouldbe
performedbyanauthorized
electricianaccordingtolocal
regulationsandinstructions
outlinedinthismanual.
Capacity shortage to the power supply
circuit or improper installation may
result in electrical shock or re.
•Properlyinstallthedevice
accordingtotheinstructionsinthis
Installation/InstructionManual.
Improper installation may result in
electric shock or re.
Caution
•Donotinstallthedeviceina
locationwhereaammablegasleak
mayoccur.
Gas may leak, collect around the
device, ignite, and/or explode.
•Donotinstallthedevicein
environmentswherelarge
amountsofoil(includingmachine),
suldizinggas,oracidic,alkaline,
chemicalspraysarepresent.
These types of substances may
damage internal parts, cause device
performance to be reduced, and cause
electrical shock.
•Donotinstallthedeviceina
bathroom,kitchen,oranyroom
wheresteamcouldform.
Condensation may develop and cause
electrical shock and/or the device to
malfunction.
•Usestandardwireswiththeproper
currentcapacity
to avoid the possibility of current leak,
excessive heat, and/or re.
•Donottouchthemaincircuitboard;
also,makesurethatdustdoesnot
accumulateonthecircuitboard.
•Wheninstallingthedeviceina
hospital,communicationfacility,
etc.,providesufcientprotection
againstfrequencynoise.
Power generators and inverters,
high-frequency medical, or radio
communication equipment may
interfere with the normal operation of
this device. Subsequently, the device
may also affect medical treatment,
image broadcasting, etc., by creating
frequency noise.
•Includesomeslackinthepower
supplywires.
Tension on the wires may cause them
to excessively heat up and/or break,
resulting in a re.
•Donotinstallthedeviceina
locationwherethereisdirect
sunlightorwherethetemperature
maybecomegreaterthan40°C
(104°F)orlessthan0°C(32°F).
If the device is installed in such
place, it may result in deformation or
malfunctions.
•Donotimmersethedeviceinwater.
Doing so may lead to electric shock or
malfunctions.
Thermostat Interface
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© 2015 Mitsubishi Electric US, Inc. 3
3.SystemConguration
Warning:Thermostatshouldbeconguredforusewithaconventionalsystem
(notheatpump).
Note:WheneitherY2orW2isleftunconnected,itisrecommendedtoset
SW2-6totheOFFposition.
1. All wiring shown should be performed with 18 AWG thermostat wire.
2. Terminals on the PAC-US444CN-1 support 20-30VAC.
3. High/medium/low fan signals are optional, and may not be available on all
thermostat models.
4. W2 and Y2 signals are optional, and may be omitted for single-stage thermostats.
Example 1: Two-stage Cooling and Heating
Note:WhenbothY2andW2areconnected,itisrecommendedtosetSW2-6to
theONposition.
Thermostat Interface
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© 2015 Mitsubishi Electric US, Inc. 4
Example 2: Single-stage Cooling and Heating
Note:WheneitherY2orW2isleftunconnected,itisrecommendedtoset
SW2-6totheOFFposition.
Example 3: Single-stage Cooling and Heating with Dedicated Fan Speed Relays
Note:Whenconnectingonlyrststagesignals(Y1/W1),itisrecommendedto
setSW2-6totheOFFposition.
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Example 4: Single-stage Cooling with Alternate Primary Heating Source
Note:Forthisconguration,itisrecommendedtosetSW2-6tothe
OFFposition.
Follow the wiring from example 2, with the following adjustments:
1. Connect thermostat W1 to the alternate heat source.
2. Connect the thermostat W2 terminal to the PAC-US444CN-1 W1 terminal.
Connector Purpose Purpose
TC Common (In) C
C Common (Out) C
TR 24VAC (In) R
R 24VAC (Out) R
G3 Fan High High Fan Speed
G2 Fan Medium Medium Fan Speed
G1 Fan Low Low Fan Speed
Y2 Y2 Stage 2 Cooling
Y1 Y1 Stage 1 Cooling
W2 W2 Stage 2 Heating
W1 W1 Stage 1 Heating
G G Fan
4.HowtoInstall
1. Choose a place where to install the PAC-US444CN-1. The device provides two
mounting holes that can be used to mechanically afx the case to a solid surface.
Double-sided tape may be used to afx the device. When using tape, ensure that
the tape is approved for use within the anticipated operating temperature ranges.
2. Install the transformer, as necessary, per building code and manufacturer’s
installation instructions.
3. Connect the PAC-US444CN-1 cable to the connector CN105 on the indoor unit
control board.
4. Connect PAC-US444CN-1 terminals using 18 AWG wire.
DeviceConguration
Initial settings can be congured via the two banks of dip switches on the circuit
board, SW1 and SW2. The circuit board can be accessed by unfastening the four
screws on the back of the case.
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DIPSwitchDenitions(FactorydefaultisOFFforallswitches):
Delayed Off
SW1-1/2: After reaching thermostat set point, the unit will continue to run for a set
period of time in order to improve efciency. The period of time is set by adjusting
SW1-1 and SW1-2 according to the following table:
SW1-1 SW1-2 Result
OFF OFF 5 minutes (Default)
ON OFF 10 minutes
OFF ON 30 minutes
ON ON 0 minutes
SW1-3/4: The indoor unit fan speed can be adjusted via the following settings:
SW1-3 SW1-4 Result
OFF OFF Auto (Default)
ON OFF Medium
OFF ON High
ON ON Custom Auto
Note: Custom Auto provides more comfortable fan speed operation vs. the more
efcient Auto (default).
Two-StageThermostatOperation
SW2-6: Adjusts indoor unit operation during stage 1 heating and stage 1 cooling
according to the following table:
SW2-6 Operationduringstage1
OFF Full capacity
ON The capacity is adjusted so that the room temperature is
adjusted (heated or cooled) at a xed rate.
Note:WheneitherY2orW2isleftunconnected,itisrecommendedto
setSW2-6totheOFFposition.WhenbothY2andW2areconnected,itis
recommendedtosetSW2-6totheONposition.
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StaticPressureSettings
SW2-1, SW2-2, SW2-3: These adjust the static pressure function settings of the
indoor unit according to the following table:
DIPswitchpositionon
PAC-US444CN-1
IndoorUnitSettings
SW2-1 SW2-2 SW2-3 Mode8 Mode10 Mode23 Mode11
OFF OFF OFF Not set Not set Not set Not set
OFF OFF ON Not set Not set Not set Not set
OFF ON OFF 21Set by SW2-4 2
OFF ON ON 22Set by SW2-4 2
ON OFF OFF 11Set by SW2-4 2
ON OFF ON 12Set by SW2-4 2
ON ON OFF 31Set by SW2-4 2
ON ON ON 32Set by SW2-4 2
*Refer to the appropriate Indoor Unit Installation Manual for Mode 8 and Mode 10
function setting denitions.
CN24OperationDuringDefrost
SW2-4: Adjusts Mode 23 function settings according to the following table:
SW2-4 Result FanandCN24
OFF Setting 2 (Default) ON
ON Setting 1 OFF
*Refer to the appropriate Indoor Unit Installation Manual for Mode 23 function setting
denitions.
FanSpeedDuringHeatingMode,ThermalOff
SW2-5: Adjusts Mode 25 initial setting (fan speed in thermal off for heating)
according to the following table:
SW2-5 Result
OFF Extra low (Default)
ON Set by Thermostat Interface
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In addition, the adapter also affects the following function settings of the connected
indoor unit:
Mode Whenusingtheadapter
Mode 1 (auto recovery after power
failure)
Always enabled
Mode 2 (room temperature detection
location)
Unused (room temperature detected by
the connected thermostat)
Mode 24 (heat offset for height) Unused
Additional function settings not addressed by the thermostat interface may be
congured by temporarily connecting an MA remote controller.
Grouping
The connection of more than one PAC-US444CN-1 to a single set of thermostat
dry-contacts is not supported.
TemperatureSensing
The PAC-US444CN-1 relies upon both the dry-contact thermostat and the
indoor unit’s thermistors in order to monitor room temperature. The thermostat’s
temperature sensing is used to set the room temperature. The indoor unit thermistor
is used when calculating cooling and heating rates of change.
5. Usage
Operate the third-party thermostat per the manufacturer’s instructions. During
normal operation, the connection of Mitsubishi remote controllers (e.g. MA/ME) is not
supported, as they will interfere with the correct operation of the PAC-US444CN-1.
Notes:
1. The indoor unit will limit the internal temperature control set point based on the
indoor unit specication.
2. Fan signals G1,G2,G3, when energized, take precedence over SW1-3&4.
3. Only fan speeds available on the IDU can be set by the Thermostat Interface.
4. The G signal is used only for operating the IDU in ventilation mode when all
cooling and heating signals are disabled.
5. When all cooling and signals are disabled, energizing G will place the IDU into
ventilation mode.
PAC-US444CN-1 Thermostat Interface Installation Instructions, May 2015
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