CONTENTS 1. GENERAL INFORMATION 2. TECHNICAL DATA AND PARTS LIST 3. TROUBLESHOOTING 4. CONTROL AND FUNCTIONS 5. FIELD WORKING...
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1. GENERAL INFORMATION 2025.01.14 SR_CH01_AU056ES_02...
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CONTENTS 1. GENERAL INFORMATION 1. Specifications....................01-1 1-1. Indoor unit ........................01-1 1-2. Outdoor unit........................01-7 2. Dimensions....................01-11 2-1. Indoor unit ........................01-11 2-2. Outdoor unit........................01-15...
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1. Specifications 1-1. Indoor unit Cassette Type Inverter, Heat pump Model name AUUH18KUAS AUUH24KUAS Power supply intake Outdoor unit Voltage 208/230 System power supply Frequency Available voltage range 187—253 Indoor unit power supply (from outdoor unit) 208/230 k→ 5.28 7.03 Rated Btu/h 18,000...
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Cassette Type Inverter, Heat pump Model name AUUH18KUAS AUUH24KUAS Material Polystyrene →hite (UTG-LCGVC→) Enclosure Approximate color of Munsell N9.25/ Color Black (UTG-LCGVCB) Cassette grille Approximate color of Munsell N2 2-1/16 × 37-3/8 × 37-3/8 (53 × 950 × 950) Dimensions in (mm) (H ×...
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Cassette Type Inverter, Heat pump Model name AUUH30KUAS AUUH36KUAS Power supply intake Outdoor unit Voltage 208/230 System power supply Frequency Available voltage range 187—253 Indoor unit power supply (from outdoor unit) 208/230 k→ 8.79 10.55 Rated Btu/h 30,000 36,000 Cooling k→...
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Cassette Type Inverter, Heat pump Model name AUUH30KUAS AUUH36KUAS Material Polystyrene →hite (UTG-LCGVC→) Enclosure Approximate color of Munsell N9.25/ Color Black (UTG-LCGVCB) Cassette grille Approximate color of Munsell N2 2-1/16 × 37-3/8 × 37-3/8 (53 × 950 × 950) Dimensions in (mm) (H ×...
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Cassette Type Inverter, Heat pump Model name AUUH42KUAS AUUH48KUAS Power supply intake Outdoor unit Voltage 208/230 System power supply Frequency Available voltage range 187—253 Indoor unit power supply (from outdoor unit) 208/230 k→ 12.31 13.48 Rated Btu/h 42,000 46,000 Cooling k→...
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Cassette Type Inverter, Heat pump Model name AUUH42KUAS AUUH48KUAS Material Polystyrene →hite (UTG-LCGVC→) Color Enclosure Approximate color of Munsell N9.25/ Black (UTG-LCGVCB) Color Cassette grille Approximate color of Munsell N2 2-1/16 × 37-3/8 × 37-3/8 (53 × 950 × 950) Dimensions in (mm) (H ×...
1-2. Outdoor unit ¢ Model: AOUH18KUAS1 Type Inverter, Heat pump Model name AOUH18KUAS1 Power supply 208/230 V~ 60 Hz Power supply intake Outdoor unit Available voltage range 187—253 V Starting current Cooling 1,318 (2,240) Airflow rate CFM (m Heating 1,154 (1,960) Type ×...
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¢ Model: AOUH24KUAS1 Type Inverter, Heat pump Model name AOUH24KUAS1 Power supply 208/230 V~ 60 Hz Power supply intake Outdoor unit Available voltage range 187—253 V Starting current Cooling 2,187 (3,715) Airflow rate CFM (m Heating 2,187 (3,715) Type × Qty Propeller fan ×...
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¢ Models: AOUH30KUAS1, AOUH36KUAS1, AOUH42KUAS1 and AOUH48KUAS1 Type Inverter, Heat pump Model name AOUH30KUAS1 AOUH36KUAS1 Power supply 208/230 V~ 60 Hz Power supply intake Outdoor unit Available voltage range 187—253 V Starting current 10.6 14.1 Cooling 2,301 (3,910) 2,502 (4,250) Airflow rate CFM (m Heating...
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Type Inverter, Heat pump Model name AOUH42KUAS1 AOUH48KUAS1 Power supply 208/230 V~ 60 Hz Power supply intake Outdoor unit Available voltage range 187—253 V Starting current 17.3 20.0 Cooling 2,443 (4,150) 2,619 (4,450) Airflow rate CFM (m Heating 2,619 (4,450) 2,619 (4,450) Type ×...
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2. Dimensions 2-1. Indoor unit ¢ Models: AUUH18KUAS and AUUH24KUAS Unit: in (mm) 31-5/16 (796) Hanging bolt position 37-3/8 (950) 13-7/16 (342) Drain hose View A 13-7/16 (342) 11-9/16 1-3/4 (293) (45) 1-9/16 (40) 5-8/16 Ceiling Wire hole (140) 3-15/16 (100) 3-15/16 (100) 9-5/16 (237)
¢ Installation space requirement Provide sufficient installation space for product safety. Unit: in (mm) Strong and durable ceiling 60 (1,500) or more 119 (3,000) or more Obstruction Floor • H1: Minimum height from bottom of the product to ceiling AUUH18-24KUAS AUUH30-48KUAS 11 (256) 12 (298)
Human Sensor (Option) NOTE: A separate device capable of controlling the human sensor (energy saving) function, such as the Touch Panel Controller, is required for use. Top view Drain Refrigerant pipe pipe Human sensor Example of sensitivity range: Unit: in (mm) 125 (3,200) 346 (8,800) 31 (800)
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2-2. Outdoor unit ¢ Model: AOUH18KUAS1 Unit: in (mm) 4-M10 hole 22-13/16 (580) 4-5/16 (109) Pitch of bolts for installation Top view 3/4 (19) 31-7/16 (799) 2-11/16 (68) 1/2 (13) 11-7/16 (290) 1-5/16 (33) 1-3/16 (30) Side view Front view Side view Airflow Hole...
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¢ Model: AOUH24KUAS1 Unit: in (mm) 5-13/16 25-9/16 (650) 5-5/8 (147) (143) 3-way valve (Gas) 3-way valve (Liquid) 1-1/4 (48) Liquid Top view Detail A Detail B 12-5/8 (320) 37 (940) 1-9/16 (40) 9/16 (14) 2-Ф7/8 (22) Cable port 2-Ф7/8 (22) Cable port 2-Ф1/8 (28) Cable port...
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¢ Models: AOUH30KUAS1, AOUH36KUAS1, AOUH42KUAS1 and AOUH48KUAS1 Unit: in (mm) 5-13/16 5-5/8 (147) 25-9/16 (650) (143) 1-7/8 (48) 1-3/8 (35.7) Top view 37 (940) 1-9/16 12-5/8 (320) 3/16 (40) 3-way valve (Liquid) 3-way valve (Gas) 2-Ф7/8 (22) 2-Ф7/8 (22) Cable port Cable port 2-Ф1/8 (28) Cable port...
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- (01-18) - 2-2. Outdoor unit 2. Dimensions...
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2. TECHNICAL DATA AND PARTS LIST 2025.01.14 SR_CH02_AU056ES_02...
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CONTENTS 2. TECHNICAL DATA AND PARTS LIST 1. Precautions....................02-1 2. Cassette Grille (option) parts list ...............02-2 2-1. Models: UTG-LCGVC→ and UTG-LCGVCB ..............02-2 3. Indoor unit parts list..................02-4 3-1. Models: AUUH18KUAS and AUUH24KUAS ..............02-4 3-2. Models: AUUH30KUAS, AUUH36KUAS, AUUH42KUAS, and AUUH48KUAS....02-8 4.
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• Service parts information and design are subject to change without notice for product improve- ment. • For the latest information of the service parts, refer to our Service Portal. https://fujitsu-general.force.com/portal/ • Precise figure of the service parts listed in this manual may differ from the actual service parts. - (02-1) -...
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2. Cassette Grille (option) parts list 2-1. Models: UTG-LCGVCW and UTG-LCGVCB ¢ Overall - (02-2) - 2-1. Models: UTG-LCGVC→ and UTG-LCGVCB 2. Cassette Grille (option) parts list...
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Item no. Part no. Part name 9381352005 Decoration panel (→hite) 9381352012 Decoration panel (Black) 9381712007 Motor case assy (→hite) 9381712014 Motor case sub assy (Black) 9381693009 Louver assy (→hite) 9381693016 Louver assy (Black) 9381711000 Corner panel assy (→hite) 9381711017 Corner panel assy (Black) 9378597020 Hook wire 9381691111...
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3. Indoor unit parts list 3-1. Models: AUUH18KUAS and AUUH24KUAS ¢ Fan and PC boards - (02-4) - 3-1. Models: AUUH18KUAS and AUUH24KUAS 3. Indoor unit parts list...
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Item no. Part no. Part name 9381794003 Float switch sub assy 9381789023 Drain pan sub assy 9375502010 Drain cap 9381303007 Turbo fan assy 9381484010 Bell-mouth hood L 9900822002 Thermistor (Room temp.) 9712450011 Power supply PCB 9900720032 Terminal block 3P 9710019005 Communication PCB 9712270329 Main PCB (18 model)
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¢ Chassis - (02-6) - 3-1. Models: AUUH18KUAS and AUUH24KUAS 3. Indoor unit parts list...
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Item no. Part no. Part name 9381912018 DC fan motor 9381793006 Drain pump sub assy 9381788002 Drain port sub assy 9377785022 Drain hose assy 9900347024 Thermistor (Pipe temp.) 9360033048 Evaporator total assy (18 model) 9360033024 Evaporator total assy (24 model) - (02-7) - 3-1.
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3-2. Models: AUUH30KUAS, AUUH36KUAS, AUUH42KUAS, and AUUH48KUAS ¢ Fan and PC boards - (02-8) - 3-2. Models: AUUH30KUAS, AUUH36KUAS, AUUH42KUAS, and AUUH48KUAS 3. Indoor unit parts list...
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Item no. Part no. Part name 9381794003 Float switch sub assy 9381789023 Drain pan sub assy 9375502010 Drain cap 9381303007 Turbo fan assy 9381345014 Bell-mouth hood H 9900822002 Thermistor (Room temp.) 9712450011 Power supply PCB 9900720032 Terminal block 3P 9710019005 Communication PCB 9712270343 Main PCB (30 model)
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¢ Chassis - (02-10) - 3-2. Models: AUUH30KUAS, AUUH36KUAS, AUUH42KUAS, and AUUH48KUAS 3. Indoor unit parts list...
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Item no. Part no. Part name 9381912001 DC fan motor 9381793006 Drain pump sub assy 9381788002 Drain port sub assy 9377785022 Drain hose assy 9900347024 Thermistor (Pipe temp.) 9360033017 Evaporator total assy (30 and 36 models) 9360033000 Evaporator total assy (45 and 54 models) - (02-11) - 3-2.
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4. Outdoor unit parts list 4-1. Model: AOUH18KUAS1 ¢ Exterior parts and Chassis - (02-12) - 4-1. Model: AOUH18KUAS1 4. Outdoor unit parts list...
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Item no. Part no. Part name 9322556028 Top panel assy 9377854001 Protective net 9322327000 Thermistor holder 9900565145 Thermistor (Outdoor temp.) 9712996052 Main PCB 9900935054 Thermistor assy 9900984014 Thermistor (Heat exchanger temp.) 9900985011 Thermistor (Compressor temp.) 9322570178 Switch cover assy 9384276001 Conduit cover 9322552365 Cabinet right assy...
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¢ Compressor - (02-14) - 4-1. Model: AOUH18KUAS1 4. Outdoor unit parts list...
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Item no. Part no. Part name 9810521002 Compressor 9322446015 4-way valve assy 9970194023 Solenoid 9970222016 Expansion valve coil 9322463029 Pulse motor valve assy 9322474001 2-way valve assy 9387831016 3-way valve assy - (02-15) - 4-1. Model: AOUH18KUAS1 4. Outdoor unit parts list...
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4-2. Model: AOUH24KUAS1 ¢ Exterior parts and chassis 13 13 - (02-16) - 4-2. Model: AOUH24KUAS1 4. Outdoor unit parts list...
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Item no. Part no. Part name 9383880001 Top panel sub assy 9383779008 Protective net 9900984038 Thermistor (Heat exchanger temp.) 9900727154 Thermistor assy 9900565152 Thermistor (Outdoor temp.) 9383607004 Thermostat holder 9383874000 Right panel sub assy 9384997005 Rear pipe cover 9712996083 Inverter PCB 9901031014 Thermistor (Heat sink temp.) 9900203061...
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¢ Compressor - (02-18) - 4-2. Model: AOUH24KUAS1 4. Outdoor unit parts list...
5-2. Outdoor unit ¢ Model: AOUH18KUAS1 Part name Exterior Part name Exterior Installation manual Cable tie Drain pipe Protection label Drain cap ¢ Models: AOUH24KUAS1, AOUH30KUAS1, AOUH36KUAS1, AOUH42KUAS1, and AOUH48KUAS1 Part name Exterior Part name Exterior Installation manual Drain pipe Protection label Drain cap - (02-27) -...
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6. Optional parts 6-1. Indoor unit ¢ Controllers Exterior Part name Model name Summary Remote controller that provides the functions you need in a sleek design →ired Remote that uniquely transforms itself to blend Controller UT↔-RVRU with any interior. (Touch Panel) Connecting point: Terminal block (↔1 and ↔2) Easy finger touch operation with LCD...
¢ Cassette Grille Exterior Part name Model name Summary This cassette grille to blow airflow in Cassette Grille UTG-LCGVC→ 360º direction by unique seamless airflow louver design. This cassette grille to blow airflow in 360º direction by unique seamless Cassette Grille UTG-LCGVCB airflow louver design.
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¢ Others Exterior Part name Model name Summary Human Sensor For circular flow cassette type. UT↔-SHZ↓C Connecting point: CN67 on Main PCB Use to connect with various peripheral devices and air conditioner PCB. External UT↔-↓→Z↓ZG Connect Kit For control output port. Connecting point: CN47 on Main PCB Air Outlet Installed at the air outlet when 3-...
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UART interface and a Modbus Modbus UT↔-VMS↓ open network. Converter Connecting point: CN65 or CN75 on Main PCB This converter can control Fujitsu General products using a third-party Thermostat UT↔-TTR↓Z thermostat controller. Converter Connecting point: Terminal block (↔1 and ↔2)
1. Error code →hen a problem occurs in the system or the connected device, the error content is notified by dis- playing the code. NOTE: This function is only available in a system with indoor or IR receiver units equipped with in- dicator lamps to show the error content.
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1-3. Error code table (Wired remote controller) The operation, timer, and economy indicators operate according to the error contents. For confirmation of the error contents, refer the flashing pattern as follows. Wired remote Error contents controller display E: 11.↓. Serial communication error (Serial reverse transfer error) (Outdoor unit) E: 11.↓.
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1-4. Error code table (Outdoor unit) The operation status is determined by the lighting up and blinking of the LED lamp. After check that ERROR LED lamp blinks, press the ENTER button once. NOTE: For the positions of LED lamp and buttons, refer to "Function settings (for 24–48 outdoor units)"...
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1-5. Error code table (Wireless LAN indicator) • →ireless LAN control system diagram example Indoor unit Internet Main PCB Cloud Wireless Mobile app Parts: Outdoor unit router (Smart device) WLAN adapter • Name of parts WLAN adapter Wireless LAN label MAC: SSID: AP- PIN:...
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1-6. How to check the error code on Mobile app If there is an abnormality on the air conditioning, refer to as follows. →hen the (error button) on the home screen is tapped, error code and error name is displayed. Error button Error code Error name...
1-7. Error code table (Mobile app) Error message Error contents Error code Serial reverse transmission error at start-up 11.1 E: 11.↓. Serial communication error (Serial Serial reverse transmission error during reverse transfer error) (Outdoor unit) 11.2 operation Serial forward transmission error at start-up 11.3 E: 11.↓.
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Error message Error contents Error code Outdoor unit trip terminal L error E: 65.↓. Trip terminal L error (Outdoor unit) 65.3 E: 71.↓. Discharge thermistor error (Outdoor Outdoor unit discharge temp. thermistor 1 error 71.1 unit) E: 72.↓. Compressor thermistor error Outdoor unit discharge temp.
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1-8. Error message for wireless LAN control (Mobile app) ¢ Error display If there is an abnormality on the wireless control system, refer to error messages as follows. Error message - (03-9) - 1-8. Error message for wireless LAN control (Mobile app) 1.
¢ Error message list • Registration error Cause Error Error message code Solution Communication failed. After Communication with the air conditioner failed. checking the following Check the following contents depending on the status of indoor contents, please try again unit wireless LAN indicator lamp or →LAN Adapter LED 2 and after a while.
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Cause Error Error message code Solution →LAN adapter password is Failed because the smartphone could not connect to the air wrong. Enter it again. conditioner. Check the following contents depending on the status of indoor →hen problems are not unit wireless LAN indicator lamp or →LAN Adapter LED 2 and resolved, there may be other operate again.
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Cause Error Error message code Solution • The air conditioner you are trying to register is already registered to another account. • Registration failed because the air conditioner cannot connect to the Internet. • Immediately after turning on the power of the air Air conditioner registration conditioner, wait for about 5 minutes before registering it.
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Cause Error Error message code Solution Registration may have failed because a problem occurred in communication with the server (cloud). 2944 Communication failed. →ait for a while and then operate again. The connected air conditioner ↔our air conditioner does not support Direct Control. 2946 cannot use the Direct control.
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• Sign in error Cause Error Error message code Solution Various settings could not be completed because Communication failed. After 4010 communication with the server (cloud) failed. checking the following 4410 contents, please try again after Check the following contents and operate again. a while.
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Cause Error Error message code Solution User information or temperature unit information could not be Loading of user information obtained because communication with the server (cloud) failed. failed. Check the following Check the following contents and operate again. contents. 4420 1.
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• General error Cause Error Error message code Solution 0100 Communication with the air conditioner failed. 0200 0300 0400 Check the following contents depending on the status of indoor 0500 unit wireless LAN indicator lamp or →LAN Adapter LED 2 and operate again.
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Cause Error Error message code Solution The outdoor unit low noise timer information could not be obtained because communication with the server (cloud) failed. Check the following contents depending on the status of indoor unit wireless LAN indicator lamp or →LAN Adapter LED 2 and operate again.
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Cause Error Error message code Solution The error history information could not be obtained because communication with the server (cloud) failed. Check the following contents depending on the status of indoor unit wireless LAN indicator lamp or →LAN Adapter LED 2 and operate again.
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Cause Error Error message code Solution Air conditioner group setting has not been completed because communication with air conditioner failed. Check the following contents depending on the status of indoor unit wireless LAN indicator lamp or →LAN Adapter LED 2 and operate again.
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Cause Error Error message code Solution Air conditioner group setting has not been completed because communication with air conditioner failed. Check the following contents depending on the status of indoor unit wireless LAN indicator lamp or →LAN Adapter LED 2 and operate again.
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Cause Error Error message code Solution Air conditioner group setting has not been completed because communication with air conditioner failed. Check the following contents depending on the status of indoor unit wireless LAN indicator lamp or →LAN Adapter LED 2 and operate again.
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Cause Error Error message code Solution Various settings could not be completed because Failed to update the screen. communication with the server (cloud) failed. After checking the following contents, please try again after Check the following contents and operate again. a while.
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2. Troubleshooting with error code 2-1. E: 11.X. Serial communication error (Serial reverse transfer error) (Outdoor unit) →ired remote Indicator Error code E: 11 controller Main PCB →hen the indoor unit cannot receive the serial signal from outdoor unit more than 2 minutes after power on, Detective actuator Outdoor unit or the indoor unit cannot receive the serial signal more...
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Check point 4. Check serial signal (Reverse transfer signal) Check serial signal (Reverse transfer signal) BLACK WHITE BLACK WHITE • Check if indicated value swings between AC 90 V and AC 270 V at the outdoor unit terminal 1 —3. •...
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2-2. E: 11.X. Serial communication error (Serial forward transfer error) (Indoor unit) →ired remote Indicator Error code E: 11 controller →hen the outdoor unit cannot receive the serial signal Detective actuator Indoor unit Main PCB from indoor unit more than 10 seconds. Connection failure Forecast of cause External cause...
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Check point 4. Check serial signal (Forward transfer signal) Check serial signal (Forward transfer signal) BLACK WHITE BLACK WHITE • Check if indicated value swings between AC 30 V and AC 130 V at outdoor unit terminal 2—3. • If it is abnormal, replace main PCB. Check point 1-2.
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2-3. E: 12.X. Wired remote controller communication error (Indoor unit) →ired remote Indicator Error code E: 12 controller Indoor unit Main PCB →hen the indoor unit cannot receive the signal from Detective actuator →ired remote controller more than 1 minute during →ired remote control normal operation.
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2-4. E: 15.X. Automatic air flow adjustment error (Indoor unit) →ired remote Indicator Error code E: 15 controller • On automatic airflow adjustment operation, when the fan speed other than 0rpm is detected at the 0rpm operation. • On automatic airflow adjustment operation, when Detective actuator Indoor unit Main PCB...
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2-5. E: 18.X. External communication error (Indoor unit) →ired remote Indicator Error code E: 18 controller External After receiving a signal from the external input and Detective actuator Indoor unit communication output PCB, the same signal has not been received for error 15 seconds.
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2-6. E: 22.X. Indoor unit capacity error (Indoor unit) →hen the total capacity of the indoor units does not Detective actuator Indoor unit main PCB match outdoor unit capacity while 3 minutes after power Indoor unit selection is incorrect. Forecast of cause Main PCB failure Check point 1.
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2-7. E: 23.X. Combination error (Outdoor unit) →ired remote Indicator Error code E: 23 controller The outdoor unit receives the serial signal of applied Detective actuator Indoor unit refrigerant information from indoor unit. Forecast of cause Incorrect indoor unit is selected. Check point 1.
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2-8. E: 26.X. Address setting error in wired remote controller (Indoor unit) →ired remote Indicator Error code E: 26 controller →ired remote controller (2-wire) • →hen the address number set by auto setting and manual setting are mixed in one remote controller group Detective actuator Indoor unit controller PCB...
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2-9. E: 29.X. Connected unit number error (Indoor unit) →ired remote Indicator Error code E: 29 controller →ired remote controller (2-wire) →hen the number of the connected indoor unit exceeds Detective actuator the limitation. Indoor unit main PCB →rong wiring of indoor unit or remote controller Number of indoor unit or remote controller in remote Forecast of cause controller group...
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2-10. E: 32.X. Indoor unit main PCB error (Indoor unit) →ired remote Indicator Error code E: 32 controller →hen power is on and there is some below case. Detective actuator Indoor unit Main PCB 1. →hen model information of EEPROM is incorrect. 2.
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2-11. E: 33.X. Indoor unit motor electricity consumption detection error (Indoor unit) →ired remote Indicator Error code E: 33 controller Indoor unit motor electricity →hen the voltage value or the current value of the motor Detective actuator consumption detection go beyond the limits Fan motor failure Forecast of cause Main PCB failure...
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2-12. E: 35.X. MANUAL AUTO button error (Indoor unit) →ired remote Indicator Error code E: 35 controller Indoor unit controller PCB →hen the MANUAL AUTO button becomes on for Detective actuator Indicator PCB consecutive 60 or more seconds. Manual auto switch MANUAL AUTO button failure Forecast of cause Controller PCB and indicator PCB failure...
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2-13. E: 39.X. Indoor unit power supply error for fan motor (Indoor unit) →ired remote Indicator Error code E: 39 controller • →hen a momentary power cut off Detective actuator Indoor unit main PCB • →hen do not start fan motor External cause Forecast of cause Connector connection failure...
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2-14. E: 3A.X. Indoor unit communication circuit (wired remote controller) error →ired remote Indicator Error code E: 3A controller →ired remote controller (2-wire) Detect the communication error of microcomputer and Detective actuator communication PCB. Indoor unit controller PCB circuit Communication PCB defective Forecast of cause Indoor unit main PCB defective Check point 1.
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2-15. E: 41.X. Room temperature sensor error (Indoor unit) →ired remote Indicator Error code E: 41 controller Indoor unit main PCB Room temperature thermistor is open or short is Detective actuator detected always. Room temperature thermistor Connector failure Forecast of cause Thermistor failure Main PCB failure Check point 1.
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2-16. E: 42.X. Indoor unit heat exchanger sensor error (Indoor unit) →ired remote Indicator Error code E: 42 controller Indoor unit main PCB →hen heat exchanger temperature thermistor open or Detective actuator Heat exchanger temperature short circuit is detected. thermistor Connector connection failure Forecast of cause Thermistor failure...
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2-17. E: 44.X. Human sensor error →ired remote Indicator Error code E: 44 controller 1. Detect the open condition of the sensor. Detective actuator Indoor unit main PCB 2. →hen signal from sensor is "L" (0 V) for more than 20 min.
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2-18. E: 51.X. Indoor unit fan motor error (Indoor unit) →ired remote Indicator Error code E: 51 controller Main PCB →hen the actual rotation number of the indoor unit fan Detective actuator Indoor unit motor is below 1/3 of the target rotation number Fan motor continuously for more than 56 seconds.
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2-19. E: 53.X. Drain pump error (Indoor unit) →ired remote Indicator Error code E: 53 controller Indoor unit main PCB Detective actuator →hen Float switch is ON for more than 3 minutes. Float switch Float switch failure Shorted connector/wire failure Forecast of cause Main PCB failure Drain pump failure...
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2-20. E: 62.X. Outdoor unit main PCB error (Outdoor unit) →ired remote Indicator Error code E: 62 controller Access to EEPROM failed due to some cause after Detective actuator Outdoor unit Main PCB outdoor unit started. External cause (Noise, temporary open, voltage drop) Forecast of cause Main PCB failure Check point 1.
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2-21. E: 63.X. Inverter error (Outdoor unit) →ired remote Indicator Error code E: 63 controller Detective actuator Outdoor unit Inverter PCB Error information received from inverter PCB Forecast of cause External cause Power supply to inverter PCB wiring disconnection or open Inverter PCB failure Outdoor unit main PCB failure...
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2-22. E: 64.X. PFC circuit error (Outdoor unit) →ired remote Indicator Error code E: 64 controller • →hen inverter input DC voltage is higher than 425 V or lower than 80 V (for 18 model) or higher than 420 V for over 3 seconds (for 24/30/36/42/48 Detective actuator Outdoor unit Main PCB...
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2-23. E: 65.X. Trip terminal L error (Outdoor unit) →ired remote Indicator Error code E: 65 controller →hen the signal from FO terminal of IPM is “L” (0 V) Detective actuator Outdoor unit Main PCB during the compressor stopping. Forecast of cause Main PCB failure Check point 1.
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2-24. E: 71.X. Discharge thermistor error (Outdoor unit) →ired remote Indicator Error code E: 71 controller Outdoor unit main PCB →hen discharge pipe temperature thermistor open or Detective actuator short circuit is detected at power on or while running the Discharge pipe temperature compressor thermistor...
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2-25. E: 72.X. Compressor thermistor error (Outdoor unit) →ired remote Indicator Error code E: 72 controller Outdoor unit main PCB →hen compressor temperature thermistor open or short Detective actuator circuit is detected at power on or while running the Compressor temperature thermistor compressor Connector failure Forecast of cause...
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2-26. E: 73.X. Heat exchanger (Middle/Outlet) temperature thermistor error (Outdoor unit) →ired remote Indicator Error code E: 73 controller Heat exchanger liquid temperature • Heat exchanger liquid temperature thermistor short thermistor or open detected Detective actuator Heat exchanger middle • Heat exchanger middle temperature thermistor temperature thermistor short or open detected...
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2-27. E: 74.X. Outdoor temperature thermistor error (Outdoor unit) →ired remote Indicator Error code E: 74 controller Outdoor unit main PCB →hen outdoor temperature thermistor open or short Detective actuator circuit is detected at power on or while running the Outdoor temperature thermistor compressor Connector failure...
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2-28. E: 77.X. Heat sink thermistor error (Outdoor unit) (24/30/36/42/48 model) →ired remote Indicator Error code E: 77 controller Detective actuator Heat sink temperature thermistor Heat sink temperature thermistor short or open detected Connector failure Forecast of cause Thermistor failure Inverter PCB failure Check point 1.
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2-29. E: 84.X. Current sensor error (Outdoor unit) →ired remote Indicator Error code E: 84 controller Main PCB →hen input current sensor has detected 0 A, while inverter compressor is operating at higher than 56 rps, Detective actuator Outdoor unit after 1 minute upon starting the compressor.
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Check point 1-2. Check external cause at Indoor and Outdoor (Voltage drop or Noise) • Instant drop: Check if there is a large load electric apparatus in the same circuit. • Momentary power failure: Check if there is a defective contact or leak current in the power sup- ply circuit.
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2-30. E: 86.X. High pressure switch error (Outdoor unit) (24/30/36/42/48 model) →ired remote Indicator Error code E: 86 controller Outdoor unit main PCB →hen pressure switch open is detected in 10 seconds Detective actuator after the power is turned on. High pressure switch High pressure switch connector disconnection or open Forecast of cause...
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2-31. E: 94.X. Trip detection (Outdoor unit) →ired remote Indicator Error code E: 94 controller Inverter PCB Protection stop by over-current generation after inverter compressor start processing completed generated Main PCB consecutively 10 times. Detective actuator Outdoor unit NOTE: The number of generations is reset when the Compressor compressor starts up.
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2-32. E: 95.X. Compressor motor control error (Outdoor unit) →ired remote Indicator Error code E: 95 controller Inverter PCB "Protection stop by "overcurrent generation at inverter compressor starting" restart" generated consecutively 50 Main PCB Detective actuator Outdoor unit times x 3 sets (total 150 times) (for 18 model) or 10 times x 3 sets (total 30 times) (for 24/30/36/42/48 Compressor model).
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2-33. E: 97.X. Outdoor unit fan motor error (Outdoor unit) →ired remote Indicator Error code E: 97 controller Inverter PCB 1. →hen outdoor fan rotation speed is less than 100 rpm in 20 seconds after fan motor starts, fan motor Main PCB stops.
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Check point 4. Check output voltage of inverter PCB Check outdoor unit circuit diagram and the voltage. (Measure at inverter PCB side connector) FAN MOTOR BLACK WHITE YELLOW BROWN NOTE: For details of wiring diagram, refer to "→iring diagrams" in Chapter 2. TECHNICAL DATA AND PARTS LIST on page 02-35.
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2-34. E: 99.X. 4-way valve error (Outdoor unit) →ired remote Indicator Error code E: 99 controller Indoor unit main PCB →hen the indoor heat exchanger temperature is compared with the room temperature, and either Heat exchanger temperature following condition is detected continuously two times, thermistor the compressor stops.
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Check point 4. Check the solenoid coil and 4-way valve NOTE: Refer solenoid coil and 4-way valve in "Service parts information" on page 03-82. • Solenoid coil Remove P60 from PCB and check the resistance value of coil. Resistance value is 1.970 kΩ (at 68°F [20°C]).
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2-35. E: A1.X. Discharge temperature error (Outdoor unit) →ired remote Indicator Error code E: A1 controller Outdoor unit main PCB Protection stop by discharge temperature ≥ 230°F Detective actuator (110°C) during compressor operation generated 2 times Discharge temperature thermistor within 24 hours. 3-way valve not opened EEV or capillary tube defective, strainer clogged Outdoor unit operation failure, foreign matter on heat...
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Check point 5. Check the refrigerant amount Check the refrigerant leakage. Check point 6. Replace the main PCB If check point 1 to 5 do not improve the symptom, replace the main PCB. - (03-63) - 2-35. E: A1.↓. Discharge temperature error (Outdoor unit) 2.
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2-36. E: A3.X. Compressor temperature error (Outdoor unit) →ired remote Indicator Error code E: A3 controller Outdoor unit main PCB Protection stop by compressor temperature ≥ 226.4°F Detective actuator (108°C) during compressor operation generated 2 times Compressor temperature thermistor within 24 hours. 3-way valve not opened EEV defective, strainer clogged Outdoor unit operation failure, foreign matter on heat...
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Check point 5. Check the refrigerant amount Check the refrigerant leakage. Check point 6. Replace the main PCB If check point 1 to 5 do not improve the symptom, replace the main PCB. - (03-65) - 2-36. E: A3.↓. Compressor temperature error (Outdoor unit) 2.
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2-37. E: AC.X. Heat sink temperature error (Outdoor unit) (24/30/36/42/48 model) →ired remote Indicator Error code E: AC controller Outdoor unit inverter PCB Protection stop by heat sink temperature ≥ 176°F (80°C) Detective actuator during heat sink operation generated 2 times within 24 Heat sink temperature thermistor hours.
3. Troubleshooting without error code 3-1. Indoor unit—No power Power supply failure Forecast of cause External cause Electrical components defective Check point 1. Check installation condition • Isn’t the breaker down? • Check loose or removed connection cable. -> If abnormal condition is found, correct it by referring to the installation manual or the “DESIGN & TECHNICAL MANUAL”.
3-2. Outdoor unit—No power Power supply failure Forecast of cause External cause Electrical components defective Check point 1. Check installation condition • Is the circuit breaker on or off? • Check loose or removed connection cable. If abnormal condition is found, correct it by referring to the installation manual or the DESIGN & TECHNICAL MANUAL.
3-3. No operation (Power is on) Setting/ Connection failure Forecast of cause External cause Electrical components defective Check point 1. Check indoor and outdoor installation condition • Indoor unit: – Check incorrect wiring between indoor unit and remote controller. – Check if there is an open cable connection.
3-4. No cooling/No heating Indoor unit error Outdoor unit error Forecast of cause Effect by surrounding environment Connection pipe/Connection wire failure Refrigeration cycle failure Check point 1. Check Indoor unit • Does Indoor unit fan run in the HIGH mode? •...
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NOTES: • Strainer normally does not have temperature difference between inlet and outlet as shown be- low. Pipe (In) Pipe (Out) • If there is a difference like shown below, there is a possibility of inside clogged. In this case, re- place the strainer.
3-5. Abnormal noise Abnormal installation (indoor unit/outdoor unit) Forecast of cause Fan failure (indoor unit/outdoor unit) Compressor failure (outdoor) Diagnosis method when abnormal noise is occurred Abnormal noise is coming from Outdoor Abnormal noise is coming from Indoor unit. unit. (Check and correct followings) (Check and correct followings) •...
3-6. Water leaking Erroneous installation Forecast of cause Drain hose failure Diagnosis method when water is spitting Diagnosis method when water leak occurs • Is main unit installed in stable condi- tion? Is the filter clogged? • Is main unit broken or deformed at the time of transportation or maintenance? MPa MPa •...
4. Troubleshooting with error code (For wireless LAN adapter) 4-1. E: 18.X. External communication error between indoor unit and wireless LAN adapter Operation indicator 1 time flash Timer indicator 8 time flash Economy indicator Continuous flash Indoor unit Indicator →ireless LAN Flashing slowly indicator Error code...
4-2. Network communication error between wireless LAN router and wireless LAN adapter Operation indicator No indication Timer indicator No indication Economy indicator No indication Indoor unit Indicator →ireless LAN Flashing slowly indicator Error code — Mobile app No indication →ireless LAN router →hen the not connection between wireless LAN adapter and wireless LAN router.
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Check point 4. Replace wireless LAN adapter. If check point 3 do not improve the symptom, replace the wireless LAN adapter and cancel the reg- istration of air conditioner on the Mobile app. After replacing the adapter, perform the pairing on the Mobile app. For the method of the Mobile app, refer to "Mobile app setting method"...
4-3. E: 18.X. Communication error Operation indicator 1 time flash Timer indicator 8 time flash Economy indicator Continuous flash Indoor unit Indicator →ireless LAN Flashing slowly indicator Error code E: 18 Mobile app E: 18.1 →ireless LAN router →hen the external communication error between indoor unit and wireless LAN adapter and network →ireless LAN adapter PCB communication error between wireless LAN router and...
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Check point 4. Check the connection cable Check the connection cable on the wireless LAN router. -> If there is loose connector, open cable or mis-wiring, correct it. Check point 5. Check the connection status. Check the connection status to the Internet and wireless LAN router. ->...
4-4. E: 18.X. Wireless LAN adapter non-energized Operation indicator 1 time flash Timer indicator 8 time flash Economy indicator Continuous flash Indoor unit Indicator →ireless LAN No indication indicator Error code E: 18 Mobile app No indication Indoor unit controller PCB →hen the voltage (DC 12 V) does not output from the Detective actuator controller PCB.
4-5. Mobile app setting method ¢ Air conditioner delete method →hen the wireless LAN adapter is replaced, delete of all air conditioner is necessary on the mobile app. Launch the mobile app. Tap the icon to display the Setting screen. Tap the “Air conditioner editing”.
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Tap the air conditioner to be deleted. Tap the Delete button. Tap the OK button. Deletion of the air conditioner registered in the mobile app is completed. - (03-81) - 4-5. Mobile app setting method 4. Troubleshooting with error code (For wireless LAN adapter)
5. Service parts information 5-1. Compressor Diagnosis method of compressor (If outdoor unit LED displays error, refer to troubleshooting) Does not start up Stops soon after starting up Abnormal noise Check if vibration noise by Is there open or loose con- Is there open or loose con- loose bolt or contact noise of nection cable?
5-2. Inverter compressor ¢ Model: AOUH18KUAS1 Check point 1. Check connection • Check terminal connection of compressor (loose or incorrect wiring) W(C) V(S) (BLACK) (WHITE) Main PCB U(R) (RED) • Check terminal connection of main PCB (loose or incorrect wiring) Main PCB W400(U) W401(V) W402(W)
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¢ Models: AOUH24KUAS1, AOUH30KUAS1, AOUH36KUAS1, AOUH42KUAS1, and AOUH48KUAS1 Check point 1. Check the terminal connection. • Check the following terminal connections of the compressor. (Loosening or incorrect wiring.) S (V) C (W) R (U): Red S (V): →hite Main PCB C (W): Black R (U) •...
5-3. Outdoor unit Electronic Expansion Valve (EEV) ¢ Model: AOUH18KUAS1 Check point 1. Check connections Check connection of connector. (Loose connector or open cable) NOTE: For details of wiring diagram, refer to "→iring diagrams" in Chapter 2. TECHNICAL DATA AND PARTS LIST on page 02-35. Check point 2.
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Check point 6. Check strainer • Strainer normally does not have temperature difference between inlet and outlet as shown be- low. Pipe (In) Pipe (Out) • If there is a difference like shown below, there is a possibility of inside clogged. In this case, replace the strainer.
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¢ Models: AOUH24KUAS1, AOUH30KUAS1, AOUH36KUAS1, AOUH42KUAS1, and AOUH48KUAS1 Check point 1. Check connections Check connection of connector. (Loose connector or open cable) NOTE: For details of wiring diagram, refer to "→iring diagrams" in Chapter 2. TECHNICAL DATA AND PARTS LIST on page 02-35. Check point 2.
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Check point 6. Check strainer • Strainer normally does not have temperature difference between inlet and outlet as shown be- low. Pipe (In) Pipe (Out) • If there is a difference like shown below, there is a possibility of inside clogged. In this case, replace the strainer.
5-4. Indoor unit fan motor Check point 1. Check rotation of fan Rotate the fan by hand when operation is off. (Check if fan is caught, dropped off or locked motor) If fan or bearing is abnormal, replace it. Check point 2. Check resistance of indoor fan motor Refer to below.
5-5. Outdoor unit fan motor Check point 1. Check rotation of fan Rotate the fan by hand when operation is off. (Check if fan is caught, dropped off or locked motor) If fan or bearing is abnormal, replace it. Check point 2. Check resistance of outdoor fan motor Refer to below.
5-7. 4-way valve coil (solenoid coil)/4-way valve Check point 1. Check connection • Check the connection of connector P60. BLACK SOLENOID COIL BLACK Check Point 2 : Check solenoid coil Remove P60 from PCB and check the resistance value of coil. Resistance value ≈...
4. CONTROL AND FUNCTIONS 2024.11.21 SR_CH04_AU056ES_01...
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CONTENTS 4. CONTROL AND FUNCTIONS 1. Rotation number control of compressor...........04-1 1-1. Cooling operation ......................04-1 1-2. Heating operation ......................04-3 1-3. Dry operation ........................04-4 1-4. Rotation number of compressor at normal start-up ............04-5 1-5. Limitation of compressor rotation number by outdoor temperature.........04-8 2.
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CONTENTS (continued) 8-7. High temperature and high pressure release control ............04-44...
1. Rotation number control of compressor 1-1. Cooling operation A sensor (room temperature thermistor) built in the indoor unit body will usually perceive difference or variation between a set temperature and present room temperature, and controls the operation rotation number of the compressor. •...
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• Limit of maximum speed based on outdoor temperature Outdoor temperature rises Outdoor temperature drops 96.8°F A zone 93.2°F (36°C) (34°C) 89.6°F B zone 86.0°F (32°C) (30°C) 69.8°F C zone 66.2°F (21°C) (19°C) 53.6°F D zone 50.0°F (12°C) (10°C) 35.6°F E zone 32.0°F (2°C)
1-2. Heating operation A sensor (room temperature thermistor) built in indoor unit body will usually perceive difference or variation between setting temperature and present room temperature, and controls operation rota- tion number of compressor. • If the room temperature is 11°F (6.0°C) lower than a set temperature, the operation rotation num- ber of compressor will attain to maximum performance.
1-3. Dry operation The rotation number of compressor shall change according to the temperature, set temperature, and room temperature variation which the room temperature sensor of the indoor unit has detected as shown in the table below. Zone is defined by set temperature and room temperature. •...
1-4. Rotation number of compressor at normal start-up ¢ Model: AOUH18KUAS1 Rotation number of compressor soon after starting is controlled as below. Rotation number VI Rotation number V Rotation number IV Rotation number III Rotation number II Rotation number I Time 1 Time 2 Time 3...
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¢ Model: AOUH24KUAS1 Rotation number of compressor soon after starting is controlled as below. Rotation number VIII Rotation number VII Rotation number VI Rotation number V Rotation number IV Rotation number III Rotation number II Rotation number I Time 1 Time 2 Time 3 Time 4...
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¢ Models: AOUH30KUAS1, AOUH36KUAS1, AOUH42KUAS1 and AOUH48KUAS1 Rotation number of compressor soon after starting is controlled as below. Rotation number X Rotation number IX Rotation number VIII Rotation number VII Rotation number VI Rotation number V Rotation number IV Rotation number III Rotation number II Rotation numbery I Time 1...
1-5. Limitation of compressor rotation number by outdoor temperature ¢ Model: AOUH18KUAS1 The minimum rotation number of compressor is limited by outdoor temperature as below. • Cooling/Dry mode F zone 100.4°F (38°C) E zone 66.2°F (19°C) D zone 50.0°F (10°C) C zone 32.0°F (0°C)
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• Heating mode F zone 66.2°F (19°C) E zone 41.0°F (5°C) D zone 32.0°F (0°C) C zone 5.0°F (-15°C) B zone -13.0°F (-25°C) A zone Unit: rps Limitation of compressor rotation number Outdoor temperature zone AOUH18KUAS1 A zone B zone C zone D zone E zone...
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¢ Models: AOUH24KUAS1, AOUH30KUAS1, AOUH36KUAS1, AOUH42KUAS1, and AOUH48KUAS1 The minimum rotation number of compressor is limited by outdoor temperature as below. • Cooling/Dry mode K zone 125.6°F (52°C) J zone 122.0°F (50°C) I zone 114.8°F (46°C) H zone 87.8°F (31°C) G zone 69.8°F (21°C)
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• Heating mode I zone 68.0°F (20°C) H zone 60.8°F (16°C) G zone 53.6°F (12°C) F zone 44.6°F (7°C) E zone 35.6°F (2°C) D zone 19.4°F (-7°C) C zone 14.0°F (-10°C) 5.0°F B zone (-15°C) A zone Unit: rps Limitation of compressor frequency Outdoor temperature AOUH30KUAS1 AOUH42KUAS1...
2. Auto changeover operation →hen the air conditioner is set to AUTO mode by remote controller, operation starts in the optimum mode from among heating, cooling, and monitoring modes. During operation, the optimum mode is automatically switched in accordance with temperature changes. The temperature can be set be- tween 64.4 °F (18 °C) and 86.0 °F (30 °C) in 1.0 °F (0.5 °C) steps.
Operation flow chart Start Ts: Setting temperarure Monitor mode Room temp. > Ts+3.6°F (2°C)? Room temp. < Ts-3.6°F (2°C)? Middle zone Auto change over is second or more? Operation mode before the monitor mode is cooling mode? Operation mode of Heating operation Cooling operation outdoor unit: Cooling?
3. Fan control Tr: Room temperature Ts: Setting temperature 3-1. Indoor fan control ¢ Fan speed Indoor fan speed is defined as below. Speed (rpm) Operation Fan mode mode HIGH MED+ LO→ Heating QUIET Cool air prevention S-LO→ HIGH LO→ Cooling/Fan QUIET Soft quiet...
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¢ Dry operation During dry operation, fan speed setting can not be changed as shown in “Fan speed” above. ¢ Heating operation Switch the airflow AUTO, and the indoor fan motor will run according to a room temperature, as be- low.
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• MIN. HEAT operation Indoor heat exchanger Indoor heat exchanger temperature rises temperature drops AUTO 102.2°F (39°C) 93.2°F (34°C) ¢ Moisture return prevention control (cooling and dry mode) Switch the airflow AUTO at cooling mode, and the indoor fan motor will run as shown below. Compressor Indoor fan setting airflow...
3-2. Outdoor fan control ¢ Outdoor fan motor This outdoor unit has a DC fan motor. (Control method is different between AC and DC motors.) ¢ Fan speed Model: AOUH18KUAS1 Fan speed is defined by outdoor temperature and compressor frequency. •...
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Model: AOUH24KUAS1 Fan speed is defined by outdoor temperature and compressor frequency. Unit: rpm Fan step Cooling or dry Heating — — — S-HIGH — • →hen the compressor frequency increases, the outdoor fan speed also changes to the higher speed.
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Models: AOUH30KUAS1 and AOUH36KUAS1 Fan speed is defined by outdoor temperature and compressor frequency. Unit: rpm Fan step Cooling or dry Heating — — — S-HIGH — • →hen the compressor frequency increases, the outdoor fan speed also changes to the higher speed.
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Models: AOUH42KUAS1 and AOUH48KUAS1 Fan speed is defined by outdoor temperature and compressor frequency. Unit: rpm Fan step Cooling or dry Heating — — — S-HIGH — • →hen the compressor frequency increases, the outdoor fan speed also changes to the higher speed.
4. Louver control 4-1. Individual louver control To independently can be set the airflow pattern of each louver as follows: This function is given priority to overall louver control. But this function is release during the following operation. • Cold air prevention control •...
4-3. Swing operation • To select up/down airflow swing operation →hen the swing signal is received, the horizontal louver starts to swing. – Swinging range • Cooling mode/dry mode/fan mode: 1 • Heating mode: 1 – →hen the indoor fan is S-LO→ or stop mode, the swing operation is interrupted and it stops at either upper end or bottom end.
5. Timer operation control 5-1. Wireless remote control On/Off timer Program timer Sleep timer Weekly timer ○ ○ ○ — ¢ On/Off timer • Off timer: →hen the clock reaches the set timer, the air conditioner will be turned off. Operation mode Stop mode Set time of timer...
¢ Sleep timer If the sleep timer is set, the room temperature is monitored and the operation is stopped auto- matically. If the operation mode or the set temperature is change after the sleep timer is set, the operation is continued according to the changed setting of the sleep timer from that time on. •...
5-2. Wired remote control Temperature On/Off timer Program timer Sleep timer Weekly timer Setback Timer ○ ○ ○ ○ ○ ¢ On/Off timer • Off timer: →hen the clock reaches the set timer, the air conditioner will be turned off. Operation mode Stop mode Set time of timer...
¢ Sleep timer If the sleep timer is set, the room temperature is monitored and the operation is stopped auto- matically. If the operation mode or the set temperature is change after the sleep timer is set, the operation is continued according to the changed setting of the sleep timer from that time on. •...
¢ Temperature Setback Timer • The temperature setback timer only changes the set temperature for 7 days, it cannot be used to start or stop air conditioner operation. • The temperature setback timer can be set to operate up to two times per day but only one temperature setting can be used.
6. Defrost operation control Tn: Outdoor unit heat exchanger temperature Ta: Outdoor temperature Tn10: Temperature at 10 minutes after compressor start Tnb: Temperature before 5 minutes Triggering condition • The defrost operation starts when outdoor unit heat exchanger temperature sensor detects the temperature lower than the values shown below.
6-1. Defrost operation in heating operation stopped If the outdoor unit is frosted when stopping the heating operation, it stops after performing the auto- matic defrosting operation. In this time, if the indoor unit operation lamp flashes slowly (6 sec on/2 sec off), the outdoor unit al- low the heat exchanger to defrost, and then stop.
7. Various control 7-1. Auto restart →hen the power was interrupted by a power failure etc. during operation, the operation contents at that time are memorized and when the power is recovered, operation is automatically started with the memorized operation contents. Operation contents memorized when the power is interrupted Operation mode Setting temperature...
7-5. Compressor preheating operation CAUTION To perform the preheat operation, turn on the power for the outdoor unit at least 12 hours before the operation. Especially in cold climate regions, the compressor may fail if the outdoor unit is on for less than 12 hours.
7-6. External electrical heater control The external electrical heater is operated as below. When the room Ts: Setting temperature temperature rises Heater : Off -1.8°F (Ts -1°C) -5.4°F (Ts -3°C) Heater : On -18.0°F (Ts -10°C) -21.6°F (Ts -12°C) Heater : Off When the room temperature drops NOTES:...
7-8. Drain pump control ¢ Drain control for cooling operation During the compressor in operation • Triggering condition The thermostat is turned on during cooling or dry mode. • Operation details The drain pump is turned on. • Release condition –...
Overflow control • Triggering condition The float switch is turned on. • Operation details – The drain pump is turned on. – →hen the operation mode is cooling or dry, operate the followings. • The compressor is stopped. • Then indoor fan control is turned off. •...
7-9. Prevention to restart for 3 minutes (3 minutes st) →hen the compressor fails to start for the number of times below, it does not enter operation status for 3 minutes. • Model: AOUH18KUAS1 Retry number Retry set number • Models: AOUH24KUAS1, AOUH30KUAS1, AOUH36KUAS1, AOUH42KUAS1, and AOUH48KUAS1 Retry number Retry set number...
7-12. Peak cut operation (for 24/30/36/42/48 model) The current value is limited to reduce the power consumption by external input. Peak cut level Level 1 Level 2 Level 3 Level 4 Forced thermostat Peak cut for rated capacity 100% NOTES: •...
7-13. Unit status monitoring and the detected value indication The wired remote controller can monitor the indoor and outdoor units' status and display the detect- ed result as a relevant ID. For details of the display method, refer to the Chapter of “Display Sensor Values” in the Installation Manual of →ired Remote Controller (Touch Panel).
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Available Sensor ID Sensor ID Item Unit Remarks 0: Off, 1: On NOTE: The value is output even if Error On/Off (External output) 00: — the function setting or rotary switch is not set. 0: Off, 1: On Indoor unit fan interlocking On/Off NOTE: The value is output even if 00: —...
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Available Sensor ID Sensor ID Item Unit Remarks Outdoor unit fan 2 total operating 11: h hours Outdoor low noise input (External 00: — 0: Off, 1: On input) 0: Off 1: Mode 4 (100%) 2: Mode 3 (75%) Outdoor peak cut (External input) 00: —...
8. Various protections 8-1. Discharge gas temperature over-rise prevention control The discharge gas temperature sensor (discharge thermistor: outdoor unit side) detects the dis- charge gas temperature. • →hen the discharge temperature becomes higher than the trigger condition, the rotation number of compressor is decreased as the table below, and it continues to decrease until the discharge tem- perature becomes lower than the trigger condition.
8-3. Current release control The rotation number of compressor is controlled so that the outdoor unit input current does not ex- ceeds current limit value set according to the outdoor temperature. The rotation number of compressor returns according to the operation mode, when the current be- comes lower than the release value.
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¢ Model: AOUH42KUAS1 Operation mode Outdoor temp. (Ta) Trigger condition Release condition 125.6°F (52°C) ≤ Ta 10.0 A 9.5 A 122.0°F (50°C) ≤ Ta < 125.6°F (52°C) 13.0 A 12.5 A 107.6°F (42°C) ≤ Ta < 122.0°F (50°C) 15.0 A 14.5 A Cooling 104.0°F (40°C) ≤...
8-4. Compressor temperature protection →hen the compressor temperature sensor detects higher than the trigger condition below, the com- pressor is stopped. →hen the compressor temperature sensor detects the release condition, the pro- tection is released. Trigger condition 226.4°F (108°C) 176.0°F (80°C) Release condition (3 minutes after compressor stop) 8-5.
8-7. High temperature and high pressure release control The compressor is controlled as follows. ¢ Model: AOUH18KUAS1 • Cooling mode Indoor unit heat exchanger Indoor unit heat exchanger temperature rises temperature drops 141.8°F (61°C) Zone A 140.0°F (60°C) 138.2°F (59°C) Zone B 129.2°F (54°C) Zone C...
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¢ Models: AOUH24KUAS1, AOUH30KUAS1, AOUH36KUAS1, AOUH42KUAS1, and AOUH48KUAS1 • Cooling mode Indoor unit heat exchanger Indoor unit heat exchanger temperature rises temperature drops 147.2°F (64°C) Zone A 140.0°F (60°C) 136.4°F (58°C) Zone B Zone C Stable zone Zone D Zone Operation Zone A Compressor is stopped.
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- (04-46) - 8-7. High temperature and high pressure release control 8. Various protections...
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5. FIELD WORKING 2024.11.21 SR_CH05_AU056ES_01...
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CONTENTS 5. FIELD WORKING 1. Function settings (for indoor unit).............05-1 1-1. Function settings by using remote controller ..............05-1 2. Function settings (for 24–48 outdoor units) ...........05-10 2-1. Control PCB and switch buttons location..............05-10 2-2. Local setting procedure ....................05-12 3. External input and output (for indoor unit) ..........05-14 3-1.
1. Function settings (for indoor unit) To adjust the functions of this product according to the installation environment, various types of function settings are available. NOTE: Incorrect settings can cause a product malfunction. 1-1. Function settings by using remote controller Some function settings can be changed on the remote controller.
1) Filter sign Select appropriate intervals for displaying the filter sign on the indoor unit according to the estimated amount of dust in the air of the room. If the indication is not required, select "No indication" (03). Function number Setting value Setting description Factory setting...
5) Room temperature control for indoor unit sensor Depending on the installed environment, correction of the room temperature sensor may be re- quired. Select the appropriate control setting according to the installed environment. The temperature of the room temperature sensor is corrected as follows: Corrected temp.
6) Room temperature control for wired remote controller sensor Depending on the installed environment, correction of the wire remote temperature sensor may be required. Select the appropriate control setting according to the installed environment. To change this setting, set Function 42 to “Both” (01). Ensure that the Thermo Sensor icon is displayed on the remote controller screen.
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9) Remote controller custom code (Only for wireless remote controller) The indoor unit custom code can be changed. Select the appropriate custom code. Function number Setting value Setting description Factory setting ♦ 10) External input control “Operation/Stop” mode or “Forced stop” mode can be selected. Function number Setting value Setting description...
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13) Switching functions for external output terminal Functions of the external output terminal can be switched. For details, refer to “External input and output”. Function number Setting value Setting description Factory setting Operation status ♦ 01—04 Cooling thermostat On Heating operation Operation/Stop 07—08 Cooling thermostat On...
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15) Operating temperature switching of external heaters Sets the temperature conditions when the external heater is ON. For details, refer to “External heater output” in "Details of control output function" on page 05-24. Setting description Setting value of function 61: Function Setting Factory...
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17) Outdoor temperature zone boundary temperature B Setting required if changing of the outdoor temperature setting for heat pump only zone is required when auxiliary heater control by outdoor temperature 1 and 3 is performed on the indoor unit. For details, refer to “External heater output” in "Details of control output function"...
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20) Standby time for auxiliary equipment operation Sets the standby time until the auxiliary equipment operation starts during primary equipment opera- tion. For details, refer to "Details of control output function" on page 05-24. Function number Setting value Setting description Factory setting Disable ♦...
2. Function settings (for 24–48 outdoor units) Perform appropriate function setting locally according to the installation environment. NOTE: Incorrect settings can cause a product malfunction. CAUTION • Before setting up the switch buttons, discharge the static electricity from your body. •...
¢ Switch buttons and the functions LED lamps S134 S133 S132 S131 S130 Switch buttons LED lamp Function or operation method Lights on while power on. (1) PO→ER/MODE Green Blinks to show the local setting on the outdoor unit or the error code. (2) ERROR Blinks during error operation.
2-2. Local setting procedure NOTE: Before performing the function setting, be sure to stop the operation of the air conditioner. ¢ Low noise mode Press the MODE switch button (S134) for 3 seconds or more to switch to “Local setting mode”. After confirming the LED lamp of PO→ER/MODE blinks 9 times, press the ENTER switch but- ton (S132).
¢ Peak cut mode Press the MODE switch button (S134) for 3 seconds or more to switch to “Local setting mode”. After confirming the LED lamp of PO→ER/MODE blinks 9 times, press the ENTER switch but- ton (S132). PUMP POWER LOW NOISE PEAK CUT DOWN...
3-1. External input • “Operation/Stop” mode or "Forced stop" mode can be selected with function setting of indoor unit. • A twisted pair cable (22 A→G) should be used. Maximum length of cable is 492 ft (150 m). • Use an external input and output cable with appropriate external dimension, depending on the number of cables to be installed.
¢ Input signal type • Indoor unit Input signal type is only "Edge". Edge • External Input and Output PCB The input signal type can be selected. Signal type (edge or pulse) can be switched by the DIP switch 2 (S→2) on the External Input and Output PCB.
3-2. External output Use an external output cable with appropriate external dimension, depending on the number of ca- bles to be installed. ¢ Indoor unit • A twisted pair cable (22 A→G) should be used. Maximum length of cable is 82 ft (25 m). •...
3-3. Setting of external input and output • Indoor unit Input Connecting point Function setting number 46 Function Operation/Stop mode 1 (Setting prohibited) Terminal Forced stop mode Operation/Stop mode 2 Output Connecting point Function setting number 60 Function Operation/Stop 01—04 Cooling thermostat On Heating thermostat On Operation/Stop...
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• External Input and Output PCB Switch setting Ex IN Ex OUT Rotary switch Edge Operation/Stop Not available Indoor unit fan Operation/Stop Error status operation Pulse Operation Stop status Indoor unit fan Forced External heater Not available Error status operation thermostat off output status...
3-4. Details of control input function ¢ Operation/Stop mode 1 • In the case of "Edge" input External Input and Output PCB Function External input Input signal Command setting Rotary switch Operation — Input of indoor unit Terminal Stop 46-00 Operation External Input and Edge...
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¢ Forced stop • In the case of "Edge" input External Input and Output PCB Function External input Input signal Command setting Rotary switch Forced stop (R.C. disabled) — Input of indoor unit Terminal Normal (R.C. enabled) 46-02 Forced stop (R.C.
¢ Operation/Stop mode 2 • In the case of "Edge" input External Input and Output PCB Function External input Input signal Command setting Rotary switch Operation (R.C. enabled) — Input of indoor unit Terminal Stop (R.C. disabled) 46-03 Operation (R.C. enabled) External Input and Edge Ex IN 1...
¢ Forced thermostat off External Input and Output External input Input signal Command Rotary switch Thermostat off External Input and 2, B, C, D Ex IN 1 Output PCB Normal operation Thermostat off External Input and 4, 7, 8, A Ex IN 1 Output PCB Normal operation...
3-5. Details of control output function ¢ Operation status External Input and Function Output PCB External output Output signal Status setting Rotary switch Operation 60-00 — Output of indoor unit CN47 60-06 Stop Operation External Input and — 1, B, C, D Ex OUT 1 Output PCB Stop...
¢ Indoor unit fan operation status External Input and Function Output PCB External output Output signal Status setting Rotary switch Fan run 60-10 — Output of indoor unit CN47 Fan stop Fan run External Input and — 2, 3, 7, 8, B, D Ex OUT 2 Output PCB Fan stop...
¢ External heater output External Input and Function Output PCB External output Output signal Control setting Rotary switch Heater on 60-11 — Output of indoor unit CN47 Heater off Heater on External Input and — 2, 3, 4, 5, 7, 9, A, B, C Ex OUT 3 Output PCB Heater off...
• Inappropriate designing and installation of external heater may cause a fire by emitted heat from the external heater. • Fujitsu General Ltd. is not responsible for inappropriate designing or installation of external heating device. - (05-27) - 3-5. Details of control output function...
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Auxiliary equipment control by room temperature Auxiliary equipment control is switchable by room temperature. Auxiliary equipment switching is per- formed for each room temperature divided to following 3 zones. Zone A Ts +0.9°F (0.5 °C) Ts: Setting temperature Ts -0.9°F (-0.5 °C) Tr: Room temperature Zone B Zone C...
Auxiliary heater control 1 Operation Condition Heater on Heater is on as shown in following diagram of heating temperature. • Heater is off as shown in following diagram of heating temperature. • Other than heating mode Heater off • Error occurred •...
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Heat pump prohibition control Perform heating by external heater only. Indoor unit is continuous thermostat off. Operation Condition Heater on Heater is on as shown in following diagram of heating temperature. • Heater is off as shown in following diagram of heating temperature. •...
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Auxiliary heater control by outdoor temperature 1 This control selects heat pump or external heater according to the outdoor temperature. →hen out- door temperature is high, the heating is performed by using heat pump only. Operation Condition Heater on Heater is on as shown in following diagram of heating temperature.
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• Operation status 46.4°F (8°C) 42.8°F (6°C) Outdoor temperature (Factory setting) -0.4°F (-18°C) -4°F (-20°C) Heat pump Heat pump Combination zone only zone prohibition zone Outdoor temperature zone * Comp. On/Off 12 V Heater * The outdoor temperature zone transition from one to another will stay in that zone for minimum of 30 min. NOTE: In following operations, compressor will be on in heat pump prohibition zone.
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Auxiliary heater control by outdoor temperature 2 This control selects heat pump or external heater according to the outdoor temperature. Even when outdoor temperature is high, the heating is performed by using both of heat pump and external heater. Operation Condition Heater on...
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• Operation status 46.4°F (8°C) 42.8°F (6°C) Outdoor temperature (Factory setting) -0.4°F (-18°C) -4°F (-20°C) Heat pump prohibition Combination zone zone Outdoor temperature zone * Comp. On/Off 12 V Heater * The outdoor temperature zone transition from one to another will stay in that zone for minimum of 30 min. NOTE: In following operations, compressor will be on in heat pump prohibition zone.
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Auxiliary heater control by outdoor temperature 3 This control selects heat pump or external heater according to the outdoor temperature. Even when outdoor temperature is high, the heating is performed by using both of heat pump and external heater. Operation Condition Heater on...
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• Operation status Heat pump only zone 46.4°F (8°C) 42.8°F (6°C) Outdoor temperature (Factory setting) -0.4°F (-18°C) -4°F (-20°C) Combination zone Outdoor temperature zone * Comp. On/Off 12 V Heater * The outdoor temperature zone transition from one to another will stay in that zone for minimum of 30 min. NOTE: In following operations, compressor will be on in heat pump prohibition zone.
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Auxiliary heat pump control • External heater output Operation Condition Heater on Heater is on as shown in following diagram of heating temperature. • Heater is off as shown in following diagram of heating temperature. • Other than heating mode Heater off •...
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Auxiliary heat pump control by outdoor temperature 1 • External heater output Operation Condition Heater on Heater is on as shown in following diagram of heating temperature. • Heater is off as shown in following diagram of heating temperature. •...
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• Operation status 46.4°F (8°C) 42.8°F (6°C) Outdoor temperature (Factory setting) -0.4°F (-18°C) -4°F (-20°C) Heat pump prohibition Combination zone zone Outdoor temperature zone * Comp. On/Off 12 V Heater * The outdoor temperature zone transition from one to another will stay in that zone for minimum of 30 min. NOTE: In following operations, compressor will be on in heat pump prohibition zone.
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Auxiliary heat pump control by outdoor temperature 2 • External heater output Operation Condition Heater on Heater is on as shown in following diagram of heating temperature. • Heater is off as shown in following diagram of heating temperature. •...
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• Operation status Heat pump prohibition zone 46.4°F (8°C) 42.8°F (6°C) Outdoor temperature (Factory setting) -0.4°F (-18°C) -4°F (-20°C) Combination zone Outdoor temperature zone * Comp. On/Off 12 V Heater * The outdoor temperature zone transition from one to another will stay in that zone for minimum of 30 min. NOTE: In following operations, compressor will be on in heat pump prohibition zone.
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Auxiliary heat pump control by outdoor temperature 3 • External heater output Operation Condition Heater on Heater is on as shown in following diagram of heating temperature. • Heater is off as shown in following diagram of heating temperature. •...
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• Operation status Heat pump prohibition zone 46.4°F (8°C) 42.8°F (6°C) Outdoor temperature (Factory setting) -0.4°F (-18°C) -4°F (-20°C) Combination zone Outdoor temperature zone * Comp. On/Off 12 V Heater * The outdoor temperature zone transition from one to another will stay in that zone for minimum of 30 min. NOTE: In following operations, compressor will be on in heat pump prohibition zone.
¢ Heating thermostat on for humidifier Indoor unit Function External output setting Situation Mode Rotary SW Heating Indoor unit fan Heating thermostat on operation thermostat on no. 60 status 60-05 CN47 Example of 60-06 Output 3 individual Not used 60-07 Output 2 connection 60-08...
4. External input and output (for 24–48 outdoor units) →ith using external input and output functions, this product can be operated inter-connectedly with an external device. Connector Input Output Remarks P580 Low noise mode — PA580 Peak cut mode — See external input/output settings for details.
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¢ Peak cut mode By performing following on-site work, operation that suppresses the current value can be enabled: The air conditioner is set to the “Peak cut mode” when closing the contact input of a commercial timer or on/off switch to a connector on the control PCB of the outdoor unit. •...
4-2. External output →ith using external output function, some status signals are transmitted to the control PCB, and the related LED lamp indicates the status of this product. ¢ Error status output Signal on air conditioner error status is generated when a malfunction occurs. •...
¢ Compressor status output Signal on compressor operation status is generated when the compressor is running. • Circuit diagram example • Output voltage (Vcc): DC 12 Outdoor unit V 50 mA or less control PCB Connected unit (Locally purchased) • *: Make the distance from Example: Connector...
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