CU-4KS31NBU Owner's Manual
Page 1
... 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. SM700877 Pay special attention when servicing the unit. 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...
... 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. SM700877 Pay special attention when servicing the unit. 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...
CU-4KS31NBU Owner's Manual
Page 2
... all items in the parts list for the corresponding unit and perform the work or circuit inspection that requires power supply for the air conditioner, is not performed correctly, are described for serious consequences if not performed correctly. Dust or incomplete connections may cause an electric shock. For the wiring between the indoor unit and outdoor unit, attach the terminal cover securely. However, even precautionary...
... all items in the parts list for the corresponding unit and perform the work or circuit inspection that requires power supply for the air conditioner, is not performed correctly, are described for serious consequences if not performed correctly. Dust or incomplete connections may cause an electric shock. For the wiring between the indoor unit and outdoor unit, attach the terminal cover securely. However, even precautionary...
CU-4KS31NBU Owner's Manual
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.... If the work is 1 Mohm or more ), make sure that the value is performed in a well-ventilated place after sufficiently recovering the refrigerant gas. Touching the fan that the new installation location has sufficient strength for the weight of the indoor unit. After repairs, make sure to your hand or finger. Warning If refrigerant gas blows off the power and pull out...
.... If the work is 1 Mohm or more ), make sure that the value is performed in a well-ventilated place after sufficiently recovering the refrigerant gas. Touching the fan that the new installation location has sufficient strength for the weight of the indoor unit. After repairs, make sure to your hand or finger. Warning If refrigerant gas blows off the power and pull out...
CU-4KS31NBU Owner's Manual
Page 35
... wide tube service valve psig (MPaG) Outdoor Unit CU-4KS24NBU Indoor Unit CS-MKS9NKU ×1 Cooling Characteristics (RH : 46%, Indoor fan speed : High fan) (230V, 60Hz) (1) Low pressure performance chart 188 (1.3) Lo fan Hi fan HH fan 174 (1.2) 160 (1.1) In87d05o°°FFor((2a27i4r°°tCCe)m) p. 86°F (30°C) 146 (1.0)77 86 95 104 (25) (30) (35) (40) Outdoor air temperature °F (°C) (2) Operating current performance...
... wide tube service valve psig (MPaG) Outdoor Unit CU-4KS24NBU Indoor Unit CS-MKS9NKU ×1 Cooling Characteristics (RH : 46%, Indoor fan speed : High fan) (230V, 60Hz) (1) Low pressure performance chart 188 (1.3) Lo fan Hi fan HH fan 174 (1.2) 160 (1.1) In87d05o°°FFor((2a27i4r°°tCCe)m) p. 86°F (30°C) 146 (1.0)77 86 95 104 (25) (30) (35) (40) Outdoor air temperature °F (°C) (2) Operating current performance...
CU-4KS31NBU Owner's Manual
Page 36
... wide tube service valve psig (MPaG) Outdoor Unit CU-4KS24NBU Indoor Unit CS-MKS12NKU ×1 Cooling Characteristics (RH : 46%, Indoor fan speed : High fan) (230V, 60Hz) (1) Low pressure performance chart 174 (1.2) Lo fan 160 (1.1) Hi fan HH fan Indoor air temp. 86°F (30°C) 80°F 75°F (27°C) (24°C) 146 (1.0) 132 (0.9)77 86 95 104 (25) (30) (35) (40) Outdoor air temperature °F (°C) (2) Operating current performance...
... wide tube service valve psig (MPaG) Outdoor Unit CU-4KS24NBU Indoor Unit CS-MKS12NKU ×1 Cooling Characteristics (RH : 46%, Indoor fan speed : High fan) (230V, 60Hz) (1) Low pressure performance chart 174 (1.2) Lo fan 160 (1.1) Hi fan HH fan Indoor air temp. 86°F (30°C) 80°F 75°F (27°C) (24°C) 146 (1.0) 132 (0.9)77 86 95 104 (25) (30) (35) (40) Outdoor air temperature °F (°C) (2) Operating current performance...
CU-4KS31NBU Owner's Manual
Page 37
..., the performance chart will vary depending on the indoor unit type. • Check each performance value in test-run mode. Low pressure at wide tube service valve psig (MPaG) Outdoor Unit CU-4KS24NBU Indoor Unit CS-MKS18NKU ×1 Cooling Characteristics (RH : 46%, Indoor fan speed : High fan) (230V, 60Hz) (1) Low pressure performance chart 174 (1.2) Lo fan 160 (1.1) HH fan Hi fan Indoor air temp. 86°F (30°C) 80°F (27...
..., the performance chart will vary depending on the indoor unit type. • Check each performance value in test-run mode. Low pressure at wide tube service valve psig (MPaG) Outdoor Unit CU-4KS24NBU Indoor Unit CS-MKS18NKU ×1 Cooling Characteristics (RH : 46%, Indoor fan speed : High fan) (230V, 60Hz) (1) Low pressure performance chart 174 (1.2) Lo fan 160 (1.1) HH fan Hi fan Indoor air temp. 86°F (30°C) 80°F (27...
CU-4KS31NBU Owner's Manual
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... outdoor unit controller (3 locations). For this reason, to measure the voltage again, first turn OFF the outdoor unit power, then, measure the voltage in Test Run mode. [Trouble symptom 1] The fan does not stop approximately 10 seconds after operation is not normal. 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 DC fan motor...
... outdoor unit controller (3 locations). For this reason, to measure the voltage again, first turn OFF the outdoor unit power, then, measure the voltage in Test Run mode. [Trouble symptom 1] The fan does not stop approximately 10 seconds after operation is not normal. 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 DC fan motor...
CU-4KS31NBU Owner's Manual
Page 79
... liquid phase. CAUTION Ether-type oil is used for compressor oil for R410A-type units, which is different from the mineral oil used , the composition will differ depending on whether it is in gaseous or liquid phase, and the basic performance of the air conditioner will be degraded because of the air conditioner may be degraded if it is a refrigerant leak the basic performance of...
... liquid phase. CAUTION Ether-type oil is used for compressor oil for R410A-type units, which is different from the mineral oil used , the composition will differ depending on whether it is in gaseous or liquid phase, and the basic performance of the air conditioner will be degraded because of the air conditioner may be degraded if it is a refrigerant leak the basic performance of...
CU-4KS31NBU Owner's Manual
Page 83
... remaining refrigerant, refer to the instructions of the refrigerant manufacturer. When charging with a refrigerant cylinder, use an electronic scale for the cylinder is listed on the unit's nameplate. CAUTION To prevent the composition of R410A from the refrigerant cylinder to the compressor. If using the service port of the wide tube service valve. (5) Recharging Be sure to charge the specified amount of refrigerant in Cooling Operation. This...
... remaining refrigerant, refer to the instructions of the refrigerant manufacturer. When charging with a refrigerant cylinder, use an electronic scale for the cylinder is listed on the unit's nameplate. CAUTION To prevent the composition of R410A from the refrigerant cylinder to the compressor. If using the service port of the wide tube service valve. (5) Recharging Be sure to charge the specified amount of refrigerant in Cooling Operation. This...
CU-4KS31NBU Owner's Manual
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... repairs. Follow instructions given in a hazardous condition. 9-8-2. This will cause the air conditioner to operate improperly and may result in "9-6. In Case Refrigerant is leaking from the unit. Use of Existing Tubing If replacing an older unit that came with a R410A unit, do not use R22. Charging Additional Refrigerant 9-7-1. Use of Existing Units Never use new refrigerant R410A for existing units which use its existing tubing. Charge additional refrigerant in this service manual or the installation manual...
... repairs. Follow instructions given in a hazardous condition. 9-8-2. This will cause the air conditioner to operate improperly and may result in "9-6. In Case Refrigerant is leaking from the unit. Use of Existing Tubing If replacing an older unit that came with a R410A unit, do not use R22. Charging Additional Refrigerant 9-7-1. Use of Existing Units Never use new refrigerant R410A for existing units which use its existing tubing. Charge additional refrigerant in this service manual or the installation manual...
CU-4KS31NBU Owner's Manual
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...-MKS12NB4U CS-KS18NB4UW Outdoor Unit CU-3KS19NBU CU-4KS24NBU CU-4KS31NBU Power Source: 60 Hz, single-phase, 230 / 208 VAC 1. Caution before Connecting Tubes Tightly 3-5. WIRING INSTRUCTIONS 22 5-1. Wiring System Diagram 5-4. For Outdoor Unit INSTALLATION INSTRUCTIONS Split System Air Conditioner This air conditioner uses the refrigerant R410A. Optional Copper Tubing Kit 1-4. Connecting Indoor Units 2-3. General Precautions on Wiring 5-2. Wiring Instructions for the Outdoor Unit 2-5. Baffle Plate for the Outdoor Unit 6. INSTALLATION PROCESS 16 3-1. Flaring...
...-MKS12NB4U CS-KS18NB4UW Outdoor Unit CU-3KS19NBU CU-4KS24NBU CU-4KS31NBU Power Source: 60 Hz, single-phase, 230 / 208 VAC 1. Caution before Connecting Tubes Tightly 3-5. WIRING INSTRUCTIONS 22 5-1. Wiring System Diagram 5-4. For Outdoor Unit INSTALLATION INSTRUCTIONS Split System Air Conditioner This air conditioner uses the refrigerant R410A. Optional Copper Tubing Kit 1-4. Connecting Indoor Units 2-3. General Precautions on Wiring 5-2. Wiring Instructions for the Outdoor Unit 2-5. Baffle Plate for the Outdoor Unit 6. INSTALLATION PROCESS 16 3-1. Flaring...
CU-4KS31NBU Owner's Manual
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... Install the outdoor unit on the air conditioner can result in this document. When Installing... Please Read Before Starting This air conditioning system meets strict safety and operating standards. Be careful not to the wiring diagram and these instructions when wiring. Carefully refer to allow contact of your certified dealer for easy maintenance. ...In a Ceiling or Wall Make sure the ceiling/wall is an important part of the refrigerant...
... Install the outdoor unit on the air conditioner can result in this document. When Installing... Please Read Before Starting This air conditioning system meets strict safety and operating standards. Be careful not to the wiring diagram and these instructions when wiring. Carefully refer to allow contact of your certified dealer for easy maintenance. ...In a Ceiling or Wall Make sure the ceiling/wall is an important part of the refrigerant...
CU-4KS31NBU Owner's Manual
Page 91
...WKH air conditioner, do not place obstacles, enclosures and grilles in front of fire, do not install wall-mounted units less than 10 ft. (3 m). Installation Site Selection 2-1. Indoor unit Drain hose Outside drainage Fig. 1 For wall-mounted units 2" (5 cm) min. 6" (15 cm) min. 2" (5 cm) min. Indoor Unit WARNING To prevent abnormal heat generation and the possibility of or surrounding the air conditioner in rooms that generate high-frequency emissions. AVOID: direct sunlight. nearby heat...
...WKH air conditioner, do not place obstacles, enclosures and grilles in front of fire, do not install wall-mounted units less than 10 ft. (3 m). Installation Site Selection 2-1. Indoor unit Drain hose Outside drainage Fig. 1 For wall-mounted units 2" (5 cm) min. 6" (15 cm) min. 2" (5 cm) min. Indoor Unit WARNING To prevent abnormal heat generation and the possibility of or surrounding the air conditioner in rooms that generate high-frequency emissions. AVOID: direct sunlight. nearby heat...
CU-4KS31NBU Owner's Manual
Page 97
.... 5b Ground Min. 8" (20 cm) Air intake Drain holes Air discharge Obstacle CAUTION A solid base must be carried out without trouble. Outdoor Unit AVOID: heat sources, exhaust fans, etc. (Fig. 5a) NO Hot air Exhaust fan Heat source damp, humid or uneven locations. 2-3. When the outdoor unit is installed in a position exposed to reduce humidity and protect the unit against possible water damage and decreased service life. (Figs. 5c and 5d...
.... 5b Ground Min. 8" (20 cm) Air intake Drain holes Air discharge Obstacle CAUTION A solid base must be carried out without trouble. Outdoor Unit AVOID: heat sources, exhaust fans, etc. (Fig. 5a) NO Hot air Exhaust fan Heat source damp, humid or uneven locations. 2-3. When the outdoor unit is installed in a position exposed to reduce humidity and protect the unit against possible water damage and decreased service life. (Figs. 5c and 5d...
CU-4KS31NBU Owner's Manual
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... refrigerant system Air Purging with the air conditioner that uses R410A, the screw diameter at the service valve charging port has been changed. Open reverse flow) (special for R410A) Hex wrench Charging hose (special for preventing valve open. NOTE Do not wind the armoring tape too tightly, since this time, the 2 refrigerant tubes (and electrical wire if local codes permit) should be sure the condensation drain hose splits...
... refrigerant system Air Purging with the air conditioner that uses R410A, the screw diameter at the service valve charging port has been changed. Open reverse flow) (special for R410A) Hex wrench Charging hose (special for preventing valve open. NOTE Do not wind the armoring tape too tightly, since this time, the 2 refrigerant tubes (and electrical wire if local codes permit) should be sure the condensation drain hose splits...
CU-4KS31NBU Owner's Manual
Page 113
.... 8. Installation Check Sheet The strength of the installation location is sufficient to close the hole in the wall. Remote controller signals are securely fastened to the terminal board. Connecting a Home Automation Device The HA (white) 4P terminal is securely connected. The power and voltage are secure and water drains properly. Drain connections are as specified. The ground wire is located on the indoor unit PCB. An air purge...
.... 8. Installation Check Sheet The strength of the installation location is sufficient to close the hole in the wall. Remote controller signals are securely fastened to the terminal board. Connecting a Home Automation Device The HA (white) 4P terminal is securely connected. The power and voltage are secure and water drains properly. Drain connections are as specified. The ground wire is located on the indoor unit PCB. An air purge...
CU-3KS19NBU/CU-4KS24NBU/CU-4KS31NBU - Installation Manual
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... 3-5. WIRING INSTRUCTIONS 22 5-1. Wiring Instructions for Installation (not supplied) 1-2. INSTALLATION CHECK SHEET 27 85264190581001 2011 CV6233187761 Please Read Before Starting 2 Model Combinations Combine indoor and outdoor units only as listed below. Type of the Flaring Method 3-3. Embedding the Tubing and Wiring 3-2. Tubing Connections 3-6. Taping the Tubes 3-8. Wiring System Diagram 5-4. For Outdoor Unit INSTALLATION INSTRUCTIONS Split System Air Conditioner This air conditioner uses the refrigerant R410A. NOTE External diameter of Outdoor Unit 2-6. Model...
... 3-5. WIRING INSTRUCTIONS 22 5-1. Wiring Instructions for Installation (not supplied) 1-2. INSTALLATION CHECK SHEET 27 85264190581001 2011 CV6233187761 Please Read Before Starting 2 Model Combinations Combine indoor and outdoor units only as listed below. Type of the Flaring Method 3-3. Embedding the Tubing and Wiring 3-2. Tubing Connections 3-6. Taping the Tubes 3-8. Wiring System Diagram 5-4. For Outdoor Unit INSTALLATION INSTRUCTIONS Split System Air Conditioner This air conditioner uses the refrigerant R410A. NOTE External diameter of Outdoor Unit 2-6. Model...
CU-3KS19NBU/CU-4KS24NBU/CU-4KS31NBU - Installation Manual
Page 3
... hold the unit, and select a location for most installation sites and maintenance conditions. When Installing... Provide a suitable air baffle. ...In a Snowy Area Install the outdoor unit on the air conditioner can cause accidental injury or death. *URXQGWKHXQLW following local electrical codes. &RQQHFWDOOZLULQJWLJKWO\/RRVHZLULQJPD\FDXVHRYHU heating at least 1.5 m away from the unit. ...In Moist or Uneven Locations Use a raised...
... hold the unit, and select a location for most installation sites and maintenance conditions. When Installing... Provide a suitable air baffle. ...In a Snowy Area Install the outdoor unit on the air conditioner can cause accidental injury or death. *URXQGWKHXQLW following local electrical codes. &RQQHFWDOOZLULQJWLJKWO\/RRVHZLULQJPD\FDXVHRYHU heating at least 1.5 m away from the unit. ...In Moist or Uneven Locations Use a raised...
CU-3KS19NBU/CU-4KS24NBU/CU-4KS31NBU - Installation Manual
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2-3. Outdoor Unit AVOID: heat sources, exhaust fans, etc. (Fig. 5a) NO Hot air Exhaust fan Heat source damp, humid or uneven locations. Air discharge 4" (10 cm) Min. 1'8" (50 cm) Fig. 5b Ground Min. 8" (20 cm) Air intake Drain holes Air discharge Obstacle CAUTION A solid base must not cover the hole of the bottom plate. install cushion rubber under unit's feet to reduce vibration and noise. (Fig. 5e) use baffle plates. When the...
2-3. Outdoor Unit AVOID: heat sources, exhaust fans, etc. (Fig. 5a) NO Hot air Exhaust fan Heat source damp, humid or uneven locations. Air discharge 4" (10 cm) Min. 1'8" (50 cm) Fig. 5b Ground Min. 8" (20 cm) Air intake Drain holes Air discharge Obstacle CAUTION A solid base must not cover the hole of the bottom plate. install cushion rubber under unit's feet to reduce vibration and noise. (Fig. 5e) use baffle plates. When the...
CU-3KS19NBU/CU-4KS24NBU/CU-4KS31NBU - Installation Manual
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... turn. (Fig. 18) (3) Clamp the tubing bundle to wall, using the gas inside the outdoor unit.) CAUTION In order to seal off the hole in the refrigerant system have undesirable effects as this will decrease the heat insulation effect. When recharging or performing other external gas, or by using the refrigerant gas cylinder or other servicing, use sealing putty to prevent charging errors with the air conditioner...
... turn. (Fig. 18) (3) Clamp the tubing bundle to wall, using the gas inside the outdoor unit.) CAUTION In order to seal off the hole in the refrigerant system have undesirable effects as this will decrease the heat insulation effect. When recharging or performing other external gas, or by using the refrigerant gas cylinder or other servicing, use sealing putty to prevent charging errors with the air conditioner...