CU-4KS31NBU Owner's Manual
Page 1
... 1 852 361 26 CU-3KS19NBU CU-4KS24NBU < Applicable Indoor Units > Wall mounted type CS-MKS7NKU CS-MKS9NKU CS-MKS12NKU CS-MKS18NKU CS-MKS24NKU Semi-concealed type CS-MKS9NB4U & CZ-18BT1U CS-MKS12NB4U & CZ-18BT1U CS-KS18NB4UW & CZ-18BT1U CU-4KS31NBU IMPORTANT These air conditioners employ new refrigerant R410A. TECHNICAL & SERVICE MANUAL OUTDOOR UNIT : CU-3KS19NBU CU-4KS24NBU CU-4KS31NBU DC INVERTER MULTI-SYSTEM AIR CONDITIONER Capacity at 230V 19,700 BTU/h 25,400 BTU/h 30,600 BTU/h Outdoor Model No.
... 1 852 361 26 CU-3KS19NBU CU-4KS24NBU < Applicable Indoor Units > Wall mounted type CS-MKS7NKU CS-MKS9NKU CS-MKS12NKU CS-MKS18NKU CS-MKS24NKU Semi-concealed type CS-MKS9NB4U & CZ-18BT1U CS-MKS12NB4U & CZ-18BT1U CS-KS18NB4UW & CZ-18BT1U CU-4KS31NBU IMPORTANT These air conditioners employ new refrigerant R410A. TECHNICAL & SERVICE MANUAL OUTDOOR UNIT : CU-3KS19NBU CU-4KS24NBU CU-4KS31NBU DC INVERTER MULTI-SYSTEM AIR CONDITIONER Capacity at 230V 19,700 BTU/h 25,400 BTU/h 30,600 BTU/h Outdoor Model No.
CU-4KS31NBU Owner's Manual
Page 2
... the power plug or power cable from the unit. Do not start or stop the air conditioner by means of scratch or deterioration. When conducting repair work only use components included in the " Warning" table. Never modify the unit. Perform all electric work according to local applicable regulations related to electrical equipment or interior wiring regulation and make sure to use to replace any power cable or lead wire showing...
... the power plug or power cable from the unit. Do not start or stop the air conditioner by means of scratch or deterioration. When conducting repair work only use components included in the " Warning" table. Never modify the unit. Perform all electric work according to local applicable regulations related to electrical equipment or interior wiring regulation and make sure to use to replace any power cable or lead wire showing...
CU-4KS31NBU Owner's Manual
Page 3
... not wash the air conditioner with good ventilation. For the repair work in a well-ventilated place after sufficiently recovering the refrigerant gas. Confirm that the new installation location has sufficient strength for the weight of the indoor unit. If the installation plate or attachment frame has deteriorated due to be relocated, confirm that the temperature around the compressor is to the unit falling. Touching the...
... not wash the air conditioner with good ventilation. For the repair work in a well-ventilated place after sufficiently recovering the refrigerant gas. Confirm that the new installation location has sufficient strength for the weight of the indoor unit. If the installation plate or attachment frame has deteriorated due to be relocated, confirm that the temperature around the compressor is to the unit falling. Touching the...
CU-4KS31NBU Owner's Manual
Page 8
... shown in this manual. Unit Specifications Outdoor Unit CU-3KS19NBU Indoor Unit CS-MKS9NKU × 2 Duct Less Type Rated Type 3-Room Multi Outdoor Unit < 230V > Number of Connectable Indoor Units 3 Number of Operatable Indoor Units 3 Voltage Rating 230V Single-Phase 60Hz Performance Total Capacity Sensible Capacity Latent Capacity Air Circulation (High) Available Voltage Range Running Amperes Power Input Power Factor EER SEER Compressor Locked Rotor Amperes Fuse or Circuit Breaker Capacity BTU/h kW BTU/h BTU/h ft3/min (m3/h) V A W % BTU/h/W BTU/Wh A A Cooling 17,000...
... shown in this manual. Unit Specifications Outdoor Unit CU-3KS19NBU Indoor Unit CS-MKS9NKU × 2 Duct Less Type Rated Type 3-Room Multi Outdoor Unit < 230V > Number of Connectable Indoor Units 3 Number of Operatable Indoor Units 3 Voltage Rating 230V Single-Phase 60Hz Performance Total Capacity Sensible Capacity Latent Capacity Air Circulation (High) Available Voltage Range Running Amperes Power Input Power Factor EER SEER Compressor Locked Rotor Amperes Fuse or Circuit Breaker Capacity BTU/h kW BTU/h BTU/h ft3/min (m3/h) V A W % BTU/h/W BTU/Wh A A Cooling 17,000...
CU-4KS31NBU Owner's Manual
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Outdoor Unit CU-3KS19NBU Indoor Unit CS-MKS9NKU ×3 Type Number of Connectable Indoor Units Number of Operatable Indoor Units Voltage Rating Electrical Rating Performance Total Capacity Sensible Capacity Latent Capacity Air Circulation (High) Available Voltage Range Running Amperes Power Input Power Factor EER Compressor Locked Rotor Amperes Fuse or Circuit Breaker Capacity BTU/h kW BTU/h BTU/h ft3/min (m3/h) V A W % BTU/h/W A A Features Control Fan Speeds Compressor Refrigerant / Amount charged at shipment Refrigerant Control Operation Sound (High) Cool Refrigerant Tubing ...
Outdoor Unit CU-3KS19NBU Indoor Unit CS-MKS9NKU ×3 Type Number of Connectable Indoor Units Number of Operatable Indoor Units Voltage Rating Electrical Rating Performance Total Capacity Sensible Capacity Latent Capacity Air Circulation (High) Available Voltage Range Running Amperes Power Input Power Factor EER Compressor Locked Rotor Amperes Fuse or Circuit Breaker Capacity BTU/h kW BTU/h BTU/h ft3/min (m3/h) V A W % BTU/h/W A A Features Control Fan Speeds Compressor Refrigerant / Amount charged at shipment Refrigerant Control Operation Sound (High) Cool Refrigerant Tubing ...
CU-4KS31NBU Owner's Manual
Page 10
... CHANGE WITHOUT NOTICE. Outdoor Unit CU-3KS19NBU Indoor Unit CS-MKS9NKU ×3 Type Number of Connectable Indoor Units Number of Operatable Indoor Units Voltage Rating Electrical Rating Performance Total Capacity Sensible Capacity Latent Capacity Air Circulation (High) Available Voltage Range Running Amperes Power Input Power Factor EER Compressor Locked Rotor Amperes Fuse or Circuit Breaker Capacity BTU/h kW BTU/h BTU/h ft3/min (m3/h) V A W % BTU/h/W A A Features Control Fan Speeds Compressor Refrigerant / Amount charged at shipment Refrigerant Control Operation Sound (High) Cool...
... CHANGE WITHOUT NOTICE. Outdoor Unit CU-3KS19NBU Indoor Unit CS-MKS9NKU ×3 Type Number of Connectable Indoor Units Number of Operatable Indoor Units Voltage Rating Electrical Rating Performance Total Capacity Sensible Capacity Latent Capacity Air Circulation (High) Available Voltage Range Running Amperes Power Input Power Factor EER Compressor Locked Rotor Amperes Fuse or Circuit Breaker Capacity BTU/h kW BTU/h BTU/h ft3/min (m3/h) V A W % BTU/h/W A A Features Control Fan Speeds Compressor Refrigerant / Amount charged at shipment Refrigerant Control Operation Sound (High) Cool...
CU-4KS31NBU Owner's Manual
Page 11
... in this manual. Outdoor Unit CU-4KS24NBU Indoor Unit CS-MKS7NKU + CS-MKS9NKU × 2 Duct Less Type Rated < 230V > Type 4-Room Multi Outdoor Unit Number of Connectable Indoor Units 4 Number of Operatable Indoor Units 4 Voltage Rating 230V Single-Phase 60Hz Performance Total Capacity Sensible Capacity Latent Capacity Air Circulation (High) Available Voltage Range Running Amperes Power Input Power Factor EER SEER Compressor Locked Rotor Amperes Fuse or Circuit Breaker Capacity BTU/h kW BTU/h BTU/h ft3/min (m3/h) V A W % BTU/h/W BTU/Wh A A Cooling 24...
... in this manual. Outdoor Unit CU-4KS24NBU Indoor Unit CS-MKS7NKU + CS-MKS9NKU × 2 Duct Less Type Rated < 230V > Type 4-Room Multi Outdoor Unit Number of Connectable Indoor Units 4 Number of Operatable Indoor Units 4 Voltage Rating 230V Single-Phase 60Hz Performance Total Capacity Sensible Capacity Latent Capacity Air Circulation (High) Available Voltage Range Running Amperes Power Input Power Factor EER SEER Compressor Locked Rotor Amperes Fuse or Circuit Breaker Capacity BTU/h kW BTU/h BTU/h ft3/min (m3/h) V A W % BTU/h/W BTU/Wh A A Cooling 24...
CU-4KS31NBU Owner's Manual
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... in this manual. Outdoor Unit CU-4KS31NBU Indoor Unit CS-MKS7NKU × 3 + CS-MKS9NKU Duct Less Type Rated Type Number of Connectable Indoor Units Number of Operatable Indoor Units Voltage Rating 4-Room Multi Outdoor Unit 4 4 230V Single-Phase 60Hz < 230V > Performance Total Capacity Sensible Capacity Latent Capacity Air Circulation (High) Available Voltage Range Running Amperes Power Input Power Factor EER SEER Compressor Locked Rotor Amperes Fuse or Circuit Breaker Capacity BTU/h kW BTU/h BTU/h ft3/min (m3/h) V A W % BTU/h/W BTU/Wh A A Cooling 29,000...
... in this manual. Outdoor Unit CU-4KS31NBU Indoor Unit CS-MKS7NKU × 3 + CS-MKS9NKU Duct Less Type Rated Type Number of Connectable Indoor Units Number of Operatable Indoor Units Voltage Rating 4-Room Multi Outdoor Unit 4 4 230V Single-Phase 60Hz < 230V > Performance Total Capacity Sensible Capacity Latent Capacity Air Circulation (High) Available Voltage Range Running Amperes Power Input Power Factor EER SEER Compressor Locked Rotor Amperes Fuse or Circuit Breaker Capacity BTU/h kW BTU/h BTU/h ft3/min (m3/h) V A W % BTU/h/W BTU/Wh A A Cooling 29,000...
CU-4KS31NBU Owner's Manual
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... Outdoor Unit : CU-4KS31NBU 1unit 2. Rating conditions are based on the following unit combination. Outdoor Unit CU-4KS31NBU Indoor Unit CS-MKS9NKU ×4 Type Number of Connectable Indoor Units Number of Operatable Indoor Units Voltage Rating Electrical Rating Performance Total Capacity Sensible Capacity Latent Capacity Air Circulation (High) Available Voltage Range Running Amperes Power Input Power Factor EER Compressor Locked Rotor Amperes Fuse or Circuit Breaker Capacity BTU/h kW BTU/h BTU/h ft3/min (m3/h) V A W % BTU/h/W A A Features Control Fan Speeds Compressor Refrigerant...
... Outdoor Unit : CU-4KS31NBU 1unit 2. Rating conditions are based on the following unit combination. Outdoor Unit CU-4KS31NBU Indoor Unit CS-MKS9NKU ×4 Type Number of Connectable Indoor Units Number of Operatable Indoor Units Voltage Rating Electrical Rating Performance Total Capacity Sensible Capacity Latent Capacity Air Circulation (High) Available Voltage Range Running Amperes Power Input Power Factor EER Compressor Locked Rotor Amperes Fuse or Circuit Breaker Capacity BTU/h kW BTU/h BTU/h ft3/min (m3/h) V A W % BTU/h/W A A Features Control Fan Speeds Compressor Refrigerant...
CU-4KS31NBU Owner's Manual
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... used to identify whether the trouble is operating. (Diagnostic procedure) * Disconnect the motor connectors and measure the voltage at the outdoor controller connector for (3) in Test Run mode. [Trouble symptom 1] The fan does not stop approximately 10 seconds after operation is started. 8-5. Important: (A) Turn OFF the power before connecting or disconnecting the motor connectors. (B) When performing voltage measurement at the DC motor connectors on Installation Instructions of Fan Motor This outdoor...
... used to identify whether the trouble is operating. (Diagnostic procedure) * Disconnect the motor connectors and measure the voltage at the outdoor controller connector for (3) in Test Run mode. [Trouble symptom 1] The fan does not stop approximately 10 seconds after operation is started. 8-5. Important: (A) Turn OFF the power before connecting or disconnecting the motor connectors. (B) When performing voltage measurement at the DC motor connectors on Installation Instructions of Fan Motor This outdoor...
CU-4KS31NBU Owner's Manual
Page 79
... (in liquid phase. Its refrigeration capacity and energy efficiency are required. 79 CAUTION Ether-type oil is used for R410A-type units, which is New Refrigerant R410A? What is different from the mineral oil used for compressor oil for R22. Thus, always charge the refrigerant while it is in gaseous state. 9. REFRIGERANT R410A: SPECIAL PRECAUTIONS WHEN SERVICING UNIT 9-1. Characteristics of refrigerant with the refrigerant recovery unit. Components (mixing proportions) HFC32...
... (in liquid phase. Its refrigeration capacity and energy efficiency are required. 79 CAUTION Ether-type oil is used for R410A-type units, which is New Refrigerant R410A? What is different from the mineral oil used for compressor oil for R22. Thus, always charge the refrigerant while it is in gaseous state. 9. REFRIGERANT R410A: SPECIAL PRECAUTIONS WHEN SERVICING UNIT 9-1. Characteristics of refrigerant with the refrigerant recovery unit. Components (mixing proportions) HFC32...
CU-4KS31NBU Owner's Manual
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... air conditioner to operate improperly and may result in liquid state only. Charge additional refrigerant in a hazardous condition. 9-8-2. Instead, completely new tubing must be used refrigerant R22 with the indoor unit. Charging Additional Refrigerant 9-7-1. When Tubes are Extended Observe the proper amount of Existing Units Never use new refrigerant R410A for existing units which use its existing tubing. Follow instructions given in this service manual or the installation manual that used . 85 Use of refrigerant...
... air conditioner to operate improperly and may result in liquid state only. Charge additional refrigerant in a hazardous condition. 9-8-2. Instead, completely new tubing must be used refrigerant R22 with the indoor unit. Charging Additional Refrigerant 9-7-1. When Tubes are Extended Observe the proper amount of Existing Units Never use new refrigerant R410A for existing units which use its existing tubing. Follow instructions given in this service manual or the installation manual that used . 85 Use of refrigerant...
CU-4KS31NBU Owner's Manual
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...-MKS24NKU CS-MKS9NB4U CS-MKS12NB4U CS-KS18NB4UW Outdoor Unit CU-3KS19NBU CU-4KS24NBU CU-4KS31NBU Power Source: 60 Hz, single-phase, 230 / 208 VAC 1. Outdoor Unit 2-4. INSTALLATION PROCESS 16 3-1. WIRING INSTRUCTIONS 22 5-1. Please Read Before Starting 2 Model Combinations Combine indoor and outdoor units only as listed below. GENERAL 4 1-1. Finishing the Installation 4. For Outdoor Unit INSTALLATION INSTRUCTIONS Split System Air Conditioner This air conditioner uses the refrigerant R410A. Indoor Unit 2-2. Tubing Connections 3-6. How to Connect...
...-MKS24NKU CS-MKS9NB4U CS-MKS12NB4U CS-KS18NB4UW Outdoor Unit CU-3KS19NBU CU-4KS24NBU CU-4KS31NBU Power Source: 60 Hz, single-phase, 230 / 208 VAC 1. Outdoor Unit 2-4. INSTALLATION PROCESS 16 3-1. WIRING INSTRUCTIONS 22 5-1. Please Read Before Starting 2 Model Combinations Combine indoor and outdoor units only as listed below. GENERAL 4 1-1. Finishing the Installation 4. For Outdoor Unit INSTALLATION INSTRUCTIONS Split System Air Conditioner This air conditioner uses the refrigerant R410A. Indoor Unit 2-2. Tubing Connections 3-6. How to Connect...
CU-4KS31NBU Owner's Manual
Page 88
...UHIULJHUDQW gas leaks during the installation. Get a partner to help for a special problem, contact our sales/service outlet or your job to a hazard or unsafe practice which can cause dripping and water damage to support or hold the unit's weight. For safe installation and trouble-free operation, you must be necessary to construct a strong wood or metal frame to the wiring diagram and these instructions when wiring.
...UHIULJHUDQW gas leaks during the installation. Get a partner to help for a special problem, contact our sales/service outlet or your job to a hazard or unsafe practice which can cause dripping and water damage to support or hold the unit's weight. For safe installation and trouble-free operation, you must be necessary to construct a strong wood or metal frame to the wiring diagram and these instructions when wiring.
CU-4KS31NBU Owner's Manual
Page 97
... protect the unit against possible water damage and decreased service life. (Figs. 5c and 5d) Fig. 5a Min. When the outdoor unit is installed in a position exposed to reduce vibration and noise. (Fig. 5e) use baffle plates. Outdoor Unit AVOID: heat sources, exhaust fans, etc. (Fig. 5a) NO Hot air Exhaust fan Heat source damp, humid or uneven locations. In general the top also must not cover the hole of...
... protect the unit against possible water damage and decreased service life. (Figs. 5c and 5d) Fig. 5a Min. When the outdoor unit is installed in a position exposed to reduce vibration and noise. (Fig. 5e) use baffle plates. Outdoor Unit AVOID: heat sources, exhaust fans, etc. (Fig. 5a) NO Hot air Exhaust fan Heat source damp, humid or uneven locations. In general the top also must not cover the hole of...
CU-4KS31NBU Owner's Manual
Page 105
... time, the 2 refrigerant tubes (and electrical wire if local codes permit) should be sure to use a vacuum pump to perform the air purge. (Never perform an air purge by using the refrigerant gas cylinder or other servicing, use sealing putty to seal off the hole in the refrigerant system Air Purging with the tubing. (2) Wrap the armoring tape from the bottom of the outdoor unit to the...
... time, the 2 refrigerant tubes (and electrical wire if local codes permit) should be sure to use a vacuum pump to perform the air purge. (Never perform an air purge by using the refrigerant gas cylinder or other servicing, use sealing putty to seal off the hole in the refrigerant system Air Purging with the tubing. (2) Wrap the armoring tape from the bottom of the outdoor unit to the...
CU-3KS19NBU/CU-4KS24NBU/CU-4KS31NBU - Installation Manual
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...Taping the Tubes 3-8. WIRING INSTRUCTIONS 22 5-1. Wiring Instructions for the Outdoor Unit 2-5. For Outdoor Unit INSTALLATION INSTRUCTIONS Split System Air Conditioner This air conditioner uses the refrigerant R410A. Indoor Unit CS-MKS7NKU CS-MKS9NKU CS-MKS12NKU CS-MKS18NKU CS-MKS24NKU CS-MKS9NB4U CS-MKS12NB4U CS-KS18NB4UW Outdoor Unit CU-3KS19NBU CU-4KS24NBU CU-4KS31NBU Power Source: 60 Hz, single-phase, 230 / 208 VAC 1. Connecting Indoor Units 2-3. Baffle Plate for the Outdoor Unit 6. Recommended Wire Length and Diameter 5-3. Wiring System Diagram 5-4. How to Connect...
...Taping the Tubes 3-8. WIRING INSTRUCTIONS 22 5-1. Wiring Instructions for the Outdoor Unit 2-5. For Outdoor Unit INSTALLATION INSTRUCTIONS Split System Air Conditioner This air conditioner uses the refrigerant R410A. Indoor Unit CS-MKS7NKU CS-MKS9NKU CS-MKS12NKU CS-MKS18NKU CS-MKS24NKU CS-MKS9NB4U CS-MKS12NB4U CS-KS18NB4UW Outdoor Unit CU-3KS19NBU CU-4KS24NBU CU-4KS31NBU Power Source: 60 Hz, single-phase, 230 / 208 VAC 1. Connecting Indoor Units 2-3. Baffle Plate for the Outdoor Unit 6. Recommended Wire Length and Diameter 5-3. Wiring System Diagram 5-4. How to Connect...
CU-3KS19NBU/CU-4KS24NBU/CU-4KS31NBU - Installation Manual
Page 3
... installation or repair step exactly as this manual. Please Read Before Starting This air conditioning system meets strict safety and operating standards. SPECIAL PRECAUTIONS WARNING When Wiring ELECTRICAL SHOCK CAN CAUSE SEVERE PERSONAL INJURY OR DEATH. When Connecting Refrigerant Tubing WARNING ‡ :KHQSHUIRUPLQJpiping work do not mix air except for easy maintenance. ...In a Ceiling or Wall Make sure the ceiling/wall is an important part...
... installation or repair step exactly as this manual. Please Read Before Starting This air conditioning system meets strict safety and operating standards. SPECIAL PRECAUTIONS WARNING When Wiring ELECTRICAL SHOCK CAN CAUSE SEVERE PERSONAL INJURY OR DEATH. When Connecting Refrigerant Tubing WARNING ‡ :KHQSHUIRUPLQJpiping work do not mix air except for easy maintenance. ...In a Ceiling or Wall Make sure the ceiling/wall is an important part...
CU-3KS19NBU/CU-4KS24NBU/CU-4KS31NBU - Installation Manual
Page 12
... as cool as possible. choose a place that is well ventilated. install in a location where at least two sides are unobstructed, so that the flow of air at the intake port or exhaust port is not blocked, and so that the fan of the outdoor unit runs at low outdoor air temperatures. 2-3. When the outdoor unit is operated at low speed when the air conditioner is installed in...
... as cool as possible. choose a place that is well ventilated. install in a location where at least two sides are unobstructed, so that the flow of air at the intake port or exhaust port is not blocked, and so that the fan of the outdoor unit runs at low outdoor air temperatures. 2-3. When the outdoor unit is operated at low speed when the air conditioner is installed in...
CU-3KS19NBU/CU-4KS24NBU/CU-4KS31NBU - Installation Manual
Page 20
... wrench Charging hose (special for preventing valve open. 3-7. The drain hose may lead to prevent charging errors with the tubing. (2) Wrap the armoring tape from the bundle and drips clear of the outdoor unit to wall, using the refrigerant gas cylinder or other servicing, use sealing putty to seal off the hole in the air may freeze and block capillary tubing water may also be...
... wrench Charging hose (special for preventing valve open. 3-7. The drain hose may lead to prevent charging errors with the tubing. (2) Wrap the armoring tape from the bundle and drips clear of the outdoor unit to wall, using the refrigerant gas cylinder or other servicing, use sealing putty to seal off the hole in the air may freeze and block capillary tubing water may also be...
