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. Pay special attention when servicing the unit. SM700877 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. Pay special attention when servicing the unit. SM700877 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
... in the parts list for the air conditioner, is described. : This symbol indicates the items requiring special attention or instruction. For the step-up capacitor attached to the electric circuit or defective arrangement results may cause an electric shock or fire. Do not perform repair work may cause an electric shock or fire. Incorrect or poor repair work on or slack in the power plug and...
... in the parts list for the air conditioner, is described. : This symbol indicates the items requiring special attention or instruction. For the step-up capacitor attached to the electric circuit or defective arrangement results may cause an electric shock or fire. Do not perform repair work may cause an electric shock or fire. Incorrect or poor repair work on or slack in the power plug and...
CU-4KS31NBU Owner's Manual
Page 3
... ground the unit. If the work , ventilate the room. When the indoor unit is to be performed, make sure to do so may cause an injury. Doing so may cause wet furniture because water left inside may cause an electric shock. Warning If refrigerant gas blows off the power and pull out the plug. Prohibit Prohibit Caution Do not wash the air conditioner with...
... ground the unit. If the work , ventilate the room. When the indoor unit is to be performed, make sure to do so may cause an injury. Doing so may cause wet furniture because water left inside may cause an electric shock. Warning If refrigerant gas blows off the power and pull out the plug. Prohibit Prohibit Caution Do not wash the air conditioner with...
CU-4KS31NBU Owner's Manual
Page 27
Temperature Charts (CU-3KS19NBU) Outdoor Unit CU-3KS19NBU Indoor Unit CS-MKS7NKU ×1 Cooling Characteristics (RH : 46%, Indoor fan speed : High fan) (230V, 60Hz) (1) Low pressure performance chart 188 (1.3) Lo fan 174 (1.2) 160 (1.1) Hi fan HH fan Indoor air temp. 86°F 80°F 75°F (30°C) (27°C) (24°C) Low pressure at wide tube service valve psig (MPaG) 146 (1.0)77 86 95 104 (25) (30) (35) (40) Outdoor air temperature °...
Temperature Charts (CU-3KS19NBU) Outdoor Unit CU-3KS19NBU Indoor Unit CS-MKS7NKU ×1 Cooling Characteristics (RH : 46%, Indoor fan speed : High fan) (230V, 60Hz) (1) Low pressure performance chart 188 (1.3) Lo fan 174 (1.2) 160 (1.1) Hi fan HH fan Indoor air temp. 86°F 80°F 75°F (30°C) (27°C) (24°C) Low pressure at wide tube service valve psig (MPaG) 146 (1.0)77 86 95 104 (25) (30) (35) (40) Outdoor air temperature °...
CU-4KS31NBU Owner's Manual
Page 28
If the tubing length is for a tubing length of a single wall-mounted indoor unit. Low pressure at wide tube service valve psig (MPaG) Outdoor Unit CU-3KS19NBU 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) Indo87o05r°°FFair((22te74m°°CCp)). 86°F (30°C) 146...
If the tubing length is for a tubing length of a single wall-mounted indoor unit. Low pressure at wide tube service valve psig (MPaG) Outdoor Unit CU-3KS19NBU 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) Indo87o05r°°FFair((22te74m°°CCp)). 86°F (30°C) 146...
CU-4KS31NBU Owner's Manual
Page 29
... wide tube service valve psig (MPaG) Outdoor Unit CU-3KS19NBU 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 (27°C) 75°F (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-3KS19NBU 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 (27°C) 75°F (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 30
... wide tube service valve psig (MPaG) Outdoor Unit CU-3KS19NBU Indoor Unit CS-MKS18NKU ×1 Cooling Characteristics (RH : 46%, Indoor fan speed : High fan) (230V, 60Hz) (1) Low pressure performance chart 174 (1.2) 160 (1.1) Lo fan HH fan Hi fan Indoor air temp. 86°F (30°C) 80°F (27°C) 75°F (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-3KS19NBU Indoor Unit CS-MKS18NKU ×1 Cooling Characteristics (RH : 46%, Indoor fan speed : High fan) (230V, 60Hz) (1) Low pressure performance chart 174 (1.2) 160 (1.1) Lo fan HH fan Hi fan Indoor air temp. 86°F (30°C) 80°F (27°C) 75°F (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 31
... wall-mounted indoor unit. The performance chart will vary. 31 Electrical performance values represent a combined indoor/outdoor value. (In this case, be sure to stop all the indoor units where performance is not being checked.) • The performance is different, the performance chart will vary depending on the indoor unit type. • Check each performance value in test-run mode. Outdoor Unit CU-3KS19NBU Indoor Unit CS-MKS9NB4U ×1 Cooling Characteristics...
... wall-mounted indoor unit. The performance chart will vary. 31 Electrical performance values represent a combined indoor/outdoor value. (In this case, be sure to stop all the indoor units where performance is not being checked.) • The performance is different, the performance chart will vary depending on the indoor unit type. • Check each performance value in test-run mode. Outdoor Unit CU-3KS19NBU Indoor Unit CS-MKS9NB4U ×1 Cooling Characteristics...
CU-4KS31NBU Owner's Manual
Page 78
... in Test Run mode. [Trouble symptom 1] The fan does not stop approximately 10 seconds after operation is outdoor unit controller trouble or motor trouble. Fan motor rotation speed varies excessively during outdoor unit operation. Trouble Diagnosis of motor rotation speed from the motor to identify whether the trouble is started. 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 the above...
... in Test Run mode. [Trouble symptom 1] The fan does not stop approximately 10 seconds after operation is outdoor unit controller trouble or motor trouble. Fan motor rotation speed varies excessively during outdoor unit operation. Trouble Diagnosis of motor rotation speed from the motor to identify whether the trouble is started. 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 the above...
CU-4KS31NBU Owner's Manual
Page 79
... the air conditioner may be degraded if it is charged while the refrigerant is in a gaseous phase or liquid phase. Thus, when there is New Refrigerant R410A? R410A is in gaseous state. Characteristics Less toxic, more attention to moisture prevention and faster replacement work compared with the refrigerant recovery unit. CAUTION Ether-type oil is used for compressor oil for R22. Its refrigeration capacity and energy...
... the air conditioner may be degraded if it is charged while the refrigerant is in a gaseous phase or liquid phase. Thus, when there is New Refrigerant R410A? R410A is in gaseous state. Characteristics Less toxic, more attention to moisture prevention and faster replacement work compared with the refrigerant recovery unit. CAUTION Ether-type oil is used for compressor oil for R22. Its refrigeration capacity and energy...
CU-4KS31NBU Owner's Manual
Page 85
... amount of Existing Tubing If replacing an older unit that came with a R410A unit, do not use R22. Retro-Fitting Existing Systems 9-8-1. This will cause the air conditioner to operate improperly and may result in liquid state only. Only then should you recharge the refrigerant. 9-8. Use of refrigerant as stated in "9-6. 9-7. Charging Additional Refrigerant 9-7-1. Follow instructions given in this service manual or the installation manual that used . 85
... amount of Existing Tubing If replacing an older unit that came with a R410A unit, do not use R22. Retro-Fitting Existing Systems 9-8-1. This will cause the air conditioner to operate improperly and may result in liquid state only. Only then should you recharge the refrigerant. 9-8. Use of refrigerant as stated in "9-6. 9-7. Charging Additional Refrigerant 9-7-1. Follow instructions given in this service manual or the installation manual that used . 85
CU-4KS31NBU Owner's Manual
Page 87
... DEVICE 27 Outdoor unit Indoor unit D 8. For Outdoor Unit INSTALLATION INSTRUCTIONS Split System Air Conditioner This air conditioner uses the refrigerant R410A. Please Read Before Starting 2 Model Combinations Combine indoor and outdoor units only as listed below. Baffle Plate for the Outdoor Unit 6. Outer Dimensions of the Flaring Method 3-3. Embedding the Tubing and Wiring 3-2. Tubing Connections 3-6. 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...
... DEVICE 27 Outdoor unit Indoor unit D 8. For Outdoor Unit INSTALLATION INSTRUCTIONS Split System Air Conditioner This air conditioner uses the refrigerant R410A. Please Read Before Starting 2 Model Combinations Combine indoor and outdoor units only as listed below. Baffle Plate for the Outdoor Unit 6. Outer Dimensions of the Flaring Method 3-3. Embedding the Tubing and Wiring 3-2. Tubing Connections 3-6. 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...
CU-4KS31NBU Owner's Manual
Page 88
... this instruction booklet before beginning. Follow each installation or repair step exactly as this manual. When Connecting Refrigerant Tubing WARNING :KHQSHUIRUPLQJpiping work do not mix air except for additional instructions. IMPORTANT! CAUTION This symbol refers to the wiring diagram and these instructions when wiring. Provide a suitable air baffle. ...In a Snowy Area Install the outdoor unit on the air conditioner can result in personal injury or product or...
... this instruction booklet before beginning. Follow each installation or repair step exactly as this manual. When Connecting Refrigerant Tubing WARNING :KHQSHUIRUPLQJpiping work do not mix air except for additional instructions. IMPORTANT! CAUTION This symbol refers to the wiring diagram and these instructions when wiring. Provide a suitable air baffle. ...In a Snowy Area Install the outdoor unit on the air conditioner can result in personal injury or product or...
CU-4KS31NBU Owner's Manual
Page 97
...), baffle plates must not cover the hole of a television or radio exists within 10' (3 m). 2-4. Install a pair of the freeze protector. DO: Outdoor unit Obstacle above choose a place as cool as seasonal winds with low air temperature 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...
...), baffle plates must not cover the hole of a television or radio exists within 10' (3 m). 2-4. Install a pair of the freeze protector. DO: Outdoor unit Obstacle above choose a place as cool as seasonal winds with low air temperature 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...
CU-4KS31NBU Owner's Manual
Page 105
... cause the tube to perform the air purge. (Never perform an air purge by using the refrigerant gas cylinder or other external gas, or by using 1 clamp approx. 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 away from entering. (Fig. 19...
... cause the tube to perform the air purge. (Never perform an air purge by using the refrigerant gas cylinder or other external gas, or by using 1 clamp approx. 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 away from entering. (Fig. 19...
CU-3KS19NBU/CU-4KS24NBU/CU-4KS31NBU - Installation Manual
Page 2
...19 Air Purging with a Vacuum Pump (for Installation (not supplied) 1-2. For Outdoor Unit INSTALLATION INSTRUCTIONS Split System Air Conditioner This air conditioner uses the refrigerant R410A. NOTE External diameter of the Flaring Method 3-3. Please Read Before Starting 2 Model Combinations Combine indoor and outdoor units only as listed below. Model No. Tools Required for Test Run) Pump Down Combination example Indoor unit B Indoor unit A Indoor unit C 5. Optional Copper Tubing Kit 1-4. Additional Materials Required for Installation 2. Indoor Unit 2-2. Diagram of...
...19 Air Purging with a Vacuum Pump (for Installation (not supplied) 1-2. For Outdoor Unit INSTALLATION INSTRUCTIONS Split System Air Conditioner This air conditioner uses the refrigerant R410A. NOTE External diameter of the Flaring Method 3-3. Please Read Before Starting 2 Model Combinations Combine indoor and outdoor units only as listed below. Model No. Tools Required for Test Run) Pump Down Combination example Indoor unit B Indoor unit A Indoor unit C 5. Optional Copper Tubing Kit 1-4. Additional Materials Required for Installation 2. Indoor Unit 2-2. Diagram of...
CU-3KS19NBU/CU-4KS24NBU/CU-4KS31NBU - Installation Manual
Page 3
... national electrical codes. Pay close attention to all you require help , and bend your knees when lifting to reduce strain on the air conditioner can cause dripping and water damage to follow the instructions in this will cause the generation of Improper Installation The manufacturer shall in refrigeration cycle. Please Read Before Starting This air conditioning system meets strict safety and operating standards...
... national electrical codes. Pay close attention to all you require help , and bend your knees when lifting to reduce strain on the air conditioner can cause dripping and water damage to follow the instructions in this will cause the generation of Improper Installation The manufacturer shall in refrigeration cycle. Please Read Before Starting This air conditioning system meets strict safety and operating standards...
CU-3KS19NBU/CU-4KS24NBU/CU-4KS31NBU - Installation Manual
Page 12
... must not cover the hole of 6" (15 cm) above choose a place as cool as seasonal winds with low air temperature in a location where at low speed when the air conditioner is designed so that the flow of the freeze protector. 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...
... must not cover the hole of 6" (15 cm) above choose a place as cool as seasonal winds with low air temperature in a location where at low speed when the air conditioner is designed so that the flow of the freeze protector. 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...
CU-3KS19NBU/CU-4KS24NBU/CU-4KS31NBU - Installation Manual
Page 20
... capillary tubing water may lead to corrosion of parts in the wall to seal off the hole in the refrigerant system Air Purging with armoring tape. When recharging or performing other servicing, use a vacuum pump to bend it enters the wall. Air Purging Air and moisture remaining in the refrigerant system have undesirable effects as this will decrease the heat insulation effect. Open reverse flow) (special...
... capillary tubing water may lead to corrosion of parts in the wall to seal off the hole in the refrigerant system Air Purging with armoring tape. When recharging or performing other servicing, use a vacuum pump to bend it enters the wall. Air Purging Air and moisture remaining in the refrigerant system have undesirable effects as this will decrease the heat insulation effect. Open reverse flow) (special...
CU-3KS19NBU/CU-4KS24NBU/CU-4KS31NBU - Installation Manual
Page 28
... hole in the wall. All service valves are secure and water drains properly. Installation Check Sheet The strength of the installation location is securely connected. Inter-unit cables are not connected anywhere along their paths. An air purge of the tubing connections has been performed. Drain connections are fully open. Inter-unit cables are being positively received. 27 A leak test of the refrigerant circuit has been conducted. Remote controller...
... hole in the wall. All service valves are secure and water drains properly. Installation Check Sheet The strength of the installation location is securely connected. Inter-unit cables are not connected anywhere along their paths. An air purge of the tubing connections has been performed. Drain connections are fully open. Inter-unit cables are being positively received. 27 A leak test of the refrigerant circuit has been conducted. Remote controller...