Panasonic CU-3KS19NBU Technical & Service Manual
  1. Manuals
  2. Brands
  3. Panasonic Manuals
  4. Air Conditioner
  5. CU-3KS19NBU
  6. Technical & service manual
Panasonic CU-3KS19NBU Technical & Service Manual

Panasonic CU-3KS19NBU Technical & Service Manual

Dc inverter multi-system air conditioner
Hide thumbs Also See for CU-3KS19NBU:
Table of Contents

Advertisement

Quick Links

See also: Installation Manual
TECHNICAL & SERVICE MANUAL
OUTDOOR UNIT : CU-3KS19NBU
DC INVERTER MULTI-SYSTEM AIR CONDITIONER
CU-3KS19NBU
CU-4KS24NBU
CU-4KS31NBU
CU-4KS24NBU
CU-4KS31NBU
Capacity at 230V
Outdoor Model No.
19,700 BTU/h
CU-3KS19NBU
CU-4KS24NBU
25,400 BTU/h
CU-4KS31NBU
30,600 BTU/h
Product Code No.
1 852 361 24
1 852 361 25
1 852 361 26
< 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
IMPORTANT
These air conditioners employ new
refrigerant R410A.
Pay special attention when
servicing the unit.
REFERENCE NO.
SM
700877

Advertisement

Table of Contents
loading
Need help?

Need help?

Do you have a question about the CU-3KS19NBU and is the answer not in the manual?

Questions and answers

Related Manuals for Panasonic CU-3KS19NBU

Summary of Contents for Panasonic CU-3KS19NBU

  • Page 1 TECHNICAL & SERVICE MANUAL OUTDOOR UNIT : CU-3KS19NBU CU-4KS24NBU CU-4KS31NBU DC INVERTER MULTI-SYSTEM AIR CONDITIONER Capacity at 230V Outdoor Model No. Product Code No. 19,700 BTU/h CU-3KS19NBU 1 852 361 24 CU-4KS24NBU 1 852 361 25 25,400 BTU/h CU-4KS31NBU 1 852 361 26 30,600 BTU/h <...

  • Page 2: Safety Precautions

    SAFETY PRECAUTIONS • Before doing repair work, please read the " SAFETY PRECAUTIONS" carefully and fully understand them. • The precautionary items here are divided into " Warning" and " Caution" items. Items in particular which may cause death or serious injury to the service personnel if the work is not performed correctly, are included in the "...
  • Page 3 Warning If refrigerant gas blows off during the work, do not touch the refrigerant gas as it may cause frostbite. Prohibit If refrigerant gas leaks during the work, ventilate the room. If refrigerant gas catches fire, harmful gas may be generated. Do not mix any gas other than the specified refrigerant gas in the refrigerating cycle.

  • Page 4: Table Of Contents

    Table of Contents Page SAFETY PRECAUTIONS ......................TABLE OF CONTENTS ........................APPLICABLE INDOOR UNITS ..................... 1. OPERATING RANGE ........................2. SPECIFICATIONS 2-1. Unit Specifications ......................2-2. Major Component Specifications ..................2-3. Other Component Specifications ..................3. DIMENSIONAL DATA ........................4. REFRIGERANT FLOW DIAGRAM 4-1.
  • Page 5 Page 9. REFRIGERANT R410A: SPECIAL PRECAUTIONS WHEN SERVICING UNIT 9-1. Characteristics of New Refrigerant R410A ................. 9-2. Checklist before Servicing ....................9-3. Tools Specifically for R410A ....................9-4. Tubing Installation Procedures .................... 9-5. In Case of Compressor Malfunction ..................9-6. In Case Refrigerant is Leaking ....................

  • Page 6: Applicable Indoor Units

    APPLICABLE INDOOR UNITS Wall Mounted Type Indoor Unit CS-MKS7NKU CS-MKS9NKU CS-MKS12NKU CS-MKS18NKU CS-MKS24NKU Multi-Outdoor Unit 3-Room CU-3KS19NBU 4-Room CU-4KS24NBU 4-Room CU-4KS31NBU Semi-Concealed Type CS-MKS9NB4U CS-MKS12NB4U CS-KS18NB4UW Indoor Unit & & & CZ-18BT1U CZ-18BT1U CZ-18BT1U Multi-Outdoor Unit 3-Room CU-3KS19NBU 4-Room CU-4KS24NBU...

  • Page 7: Operating Range

    1. OPERATING RANGE Temperature Indoor Air Intake Temp. Outdoor Air Intake Temp. Maximum 95 °F DB / 71 °F WB 115 °F DB Cooling Minimum 67 °F DB / 57 °F WB 14 °F DB...

  • Page 8: Specifications

    For other combination unit, please refer to the "Unit Combination Tables" in this manual. Indoor Unit : CS-MKS9NKU 2units Outdoor Unit : CU-3KS19NBU 1unit The combination indoor unit is AHRI 210/240. 2. Rating conditions are: Cooling : Indoor air temp.
  • Page 9 For other combination unit, please refer to the "Unit Combination Tables" in this manual. Indoor Unit : CS-MKS9NKU 3units Outdoor Unit : CU-3KS19NBU 1unit 2. Rating conditions are: Cooling : Indoor air temp. 80 °F DB / 67 °F WB...
  • Page 10 For other combination unit, please refer to the "Unit Combination Tables" in this manual. Indoor Unit : CS-MKS9NKU 3units Outdoor Unit : CU-3KS19NBU 1unit 2. Rating conditions are: Cooling : Indoor air temp. 80 °F DB / 67 °F WB...
  • Page 11 Outdoor Unit CU-4KS24NBU Indoor Unit CS-MKS7NKU + CS-MKS9NKU × 2 < 230V > Duct Less Type Rated Type 4-Room Multi Outdoor Unit Number of Connectable Indoor Units Number of Operatable Indoor Units Voltage Rating 230V Single-Phase 60Hz Cooling Total Capacity BTU/h 24,200 ( 9,800 to 25,400 )
  • Page 12 Outdoor Unit CU-4KS24NBU Indoor Unit CS-MKS9NKU × 3 < 230V > Type 4-Room Multi Outdoor Unit Number of Connectable Indoor Units Number of Operatable Indoor Units Voltage Rating 230V Single-Phase 60Hz Cooling Total Capacity BTU/h 25,400 ( 9,800 to 25,400 ) 7.50 ( 2.90 to 7.50 ) Sensible Capacity...
  • Page 13 Outdoor Unit CU-4KS24NBU Indoor Unit CS-MKS9NKU × 3 < 208V > Type 4-Room Multi Outdoor Unit Number of Connectable Indoor Units Number of Operatable Indoor Units Voltage Rating 208V Single-Phase 60Hz Cooling Total Capacity BTU/h 24,400 ( 9,800 to 24,400 ) 7.20 ( 2.90 to 7.20 ) Sensible Capacity...
  • Page 14 Outdoor Unit CU-4KS31NBU Indoor Unit CS-MKS7NKU × 3 + CS-MKS9NKU < 230V > Duct Less Type Rated Type 4-Room Multi Outdoor Unit Number of Connectable Indoor Units Number of Operatable Indoor Units Voltage Rating 230V Single-Phase 60Hz Cooling Total Capacity BTU/h 29,000 ( 9,800 to 29,000 )
  • Page 15 Outdoor Unit CU-4KS31NBU Indoor Unit CS-MKS9NKU × 4 < 230V > Type 4-Room Multi Outdoor Unit Number of Connectable Indoor Units Number of Operatable Indoor Units Voltage Rating 230V Single-Phase 60Hz Cooling Total Capacity BTU/h 30,600 ( 9,800 to 30,600 ) 9.00 ( 2.90 to 9.00 ) Sensible Capacity...
  • Page 16 Outdoor Unit CU-4KS31NBU Indoor Unit CS-MKS9NKU × 4 < 208V > Type 4-Room Multi Outdoor Unit Number of Connectable Indoor Units Number of Operatable Indoor Units Voltage Rating 208V Single-Phase 60Hz Cooling Total Capacity BTU/h 28,600 ( 9,800 to 28,600 ) 8.40 ( 2.90 to 8.40 ) Sensible Capacity...

  • Page 17: Major Component Specifications

    2-2. Major Component Specifications 2-2-1. Outdoor Unit Outdoor Unit CU-3KS19NBU Control PCB Part No. CB-CU-3KS19NBU Controls Microprocessor Control Circuit Fuse 250V 25A Compressor Type DC Twin Rotary (Hermetic) Compressor Model / Nominal Output 5KD240XAB21 / 1,700W Compressor Oil ... Amount Pints (cc) FV50S ...
  • Page 18 Outdoor Unit CU-4KS24NBU Control PCB Part No. CB-CU-4KS24NBU Controls Microprocessor Control Circuit Fuse 250V 25A Compressor Type DC Twin Rotary (Hermetic) Compressor Model / Nominal Output 5KD240XAB21 / 1,700W Compressor Oil ... Amount Pints (cc) FV50S ... 1.91 (900) Coil Resistance (Ambient Temp. 68 °F (20 °C)) U - V : 0.720 V - W :...
  • Page 19 Outdoor Unit CU-4KS31NBU Control PCB Part No. CB-CU-4KS31NBU Controls Microprocessor Control Circuit Fuse 250V 25A Compressor Type DC Twin Rotary (Hermetic) Compressor Model / Nominal Output 5JD420XAB22 / 3,000W Compressor Oil ... Amount Pints (cc) FV50S ... 2.55 (1,200) Coil Resistance (Ambient Temp. 68 °F (20 °C)) U - V : 0.435 V - W :...

  • Page 20: Other Component Specifications

    2-3. Other Component Specifications Quantity of Sensor Model No. Sensor Name of sensor CU-3KS19NBU CU-4KS24NBU CU-4KS31NBU Outdoor air temp sensor TKS295B Outdoor heat exchanger sensor TKS292B AW / AN sensor TKS292B 1 / 1 1 / 1 1 / 1...

  • Page 21: Dimensional Data

    3. DIMENSIONAL DATA Outdoor Unit CU-3KS19NBU 23-15/16 5-11/32 15/32 11-17/32 35-7/16(900) 2-15/16 Wide tube service valve dia.3/8" (9.52) × 3 Narrow tube service valve dia.1/4" (6.35) × 3 2-1/32 4-1/2 1-13/16 2-1/16 Unit: inch(mm) (852-0-0010-11500-0)
  • Page 22 Outdoor Unit CU-4KS24NBU 23-15/16 5-11/32 15/32 11-17/32 35-7/16(900) 2-15/16 Wide tube service valve dia.1/2" (12.70) × 1 Narrow tube service valve dia.1/4" (6.35) × 4 Wide tube service valve dia.3/8" (9.52) × 3 2-1/32 4-1/2 1-13/16 2-1/16 2-13/32 Unit: inch(mm) (852-0-0010-20500-0)
  • Page 23 Outdoor Unit CU-4KS31NBU 23-15/16 5-11/32 15/32 11-17/32 35-7/16(900) 2-15/16 Wide tube service valve dia.1/2" (12.70) × 2 Narrow tube service valve dia.1/4" (6.35) × 4 Wide tube service valve dia.3/8" (9.52) × 2 2-1/32 4-1/2 1-13/16 2-1/16 2-13/32 Unit: inch(mm) (852-0-0010-20600-0)

  • Page 24: Refrigerant Flow Diagram

    4. REFRIGERANT FLOW DIAGRAM 4-1. Refrigerant Flow Diagram Outdoor Unit CU-3KS19NBU Indoor unit Outdoor unit Service valve on wide tube Wide tube Main O.D.3/8" accumulator accumulator O.D.3/8" O.D.3/8" High pressure Header switch H.P. Electric expansion valve Service valve on narrow tube Narrow tube O.D.1/4"...
  • Page 25 Outdoor Unit CU-4KS24NBU Indoor unit Outdoor unit Service valve on wide tube Wide tube Main O.D.1/2" accumulator accumulator O.D.3/8" High pressure O.D.3/8" switch H.P. O.D.3/8" Header Electric expansion Service valve on valve narrow tube Narrow tube O.D.1/4" O.D.1/4" O.D.1/4" O.D.1/4" Strainer Header Cooling cycle...
  • Page 26 Outdoor Unit CU-4KS31NBU Indoor unit Outdoor unit Service valve on wide tube Wide tube Main O.D.1/2" accumulator accumulator O.D.1/2" O.D.3/8" High pressure switch H.P. O.D.3/8" Header Electric expansion Service valve on valve narrow tube Narrow tube O.D.1/4" O.D.1/4" O.D.1/4" O.D.1/4" Strainer Header Cooling cycle...

  • Page 27: Performance Data

    5. PERFORMANCE DATA 5-1. Temperature Charts 5-1-1. 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 Lo fan Hi fan HH fan (1.3)
  • Page 28 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 Lo fan Hi fan HH fan (1.3) (1.2) (1.1) (1.0) 77 (25) (30) (35) (40) Outdoor air temperature °F (°C)
  • Page 29 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 Lo fan Hi fan HH fan (1.2) (1.1) (1.0) (0.9) 77 (25) (30) (35) (40) Outdoor air temperature °F (°C)
  • Page 30 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 HH fan Lo fan Hi fan (1.2) (1.1) (1.0) (0.9) (25) (30) (35) (40) Outdoor air temperature °F (°C)
  • Page 31 Outdoor Unit CU-3KS19NBU Indoor Unit CS-MKS9NB4U × 1 Cooling Characteristics (RH : 46%, Indoor fan speed : High fan) (230V, 60Hz) (1) Low pressure performance chart Lo fan Hi fan HH fan (1.2) (1.1) (1.0) (0.9) 77 (25) (30) (35) (40) Outdoor air temperature °F (°C)
  • Page 32 Outdoor Unit CU-3KS19NBU Indoor Unit CS-MKS12NB4U × 1 Cooling Characteristics (RH : 46%, Indoor fan speed : High fan) (230V, 60Hz) (1) Low pressure performance chart (1.2) Lo fan Hi fan HH fan (1.1) (1.0) (0.9) (25) (30) (35) (40) Outdoor air temperature °F (°C)
  • Page 33 Outdoor Unit CU-3KS19NBU Indoor Unit CS-KS18NB4UW × 1 Cooling Characteristics (RH : 46%, Indoor fan speed : High fan) (230V, 60Hz) (1) Low pressure performance chart (1.2) HH fan Lo fan Hi fan (1.1) (1.0) (0.9) (25) (30) (35) (40) Outdoor air temperature °F (°C)
  • Page 34 5-1-2. Temperature Charts (CU-4KS24NBU) Outdoor Unit CU-4KS24NBU Indoor Unit CS-MKS7NKU × 1 Cooling Characteristics (RH : 46%, Indoor fan speed : High fan) (230V, 60Hz) (1) Low pressure performance chart Lo fan Hi fan HH fan (1.3) (1.2) (1.1) (1.0) 77 (25) (30) (35)
  • Page 35 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 Lo fan Hi fan HH fan (1.3) (1.2) (1.1) (1.0) 77 (25) (30) (35) (40) Outdoor air temperature °F (°C) (2) Operating current performance chart...
  • Page 36 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 Lo fan Hi fan HH fan (1.2) (1.1) (1.0) (0.9) 77 (25) (30) (35) (40) Outdoor air temperature °F (°C) (2) Operating current performance chart...
  • Page 37 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 HH fan Lo fan Hi fan (1.2) (1.1) (1.0) (0.9) (25) (30) (35) (40) Outdoor air temperature °F (°C) (2) Operating current performance chart Lo fan...
  • Page 38 Outdoor Unit CU-4KS24NBU Indoor Unit CS-MKS24NKU × 1 Cooling Characteristics (RH : 46%, Indoor fan speed : High fan) (230V, 60Hz) (1) Low pressure performance chart Lo fan Hi fan HH fan (1.2) (1.1) (1.0) (0.9) (25) (30) (35) (40) Outdoor air temperature °F (°C) (2) Operating current performance chart HH fan...
  • Page 39 Outdoor Unit CU-4KS24NBU Indoor Unit CS-MKS9NB4U × 1 Cooling Characteristics (RH : 46%, Indoor fan speed : High fan) (230V, 60Hz) (1) Low pressure performance chart Lo fan Hi fan HH fan (1.2) (1.1) (1.0) (0.9) 77 (25) (30) (35) (40) Outdoor air temperature °F (°C) (2) Operating current performance chart...
  • Page 40 Outdoor Unit CU-4KS24NBU Indoor Unit CS-MKS12NB4U × 1 Cooling Characteristics (RH : 46%, Indoor fan speed : High fan) (230V, 60Hz) (1) Low pressure performance chart (1.2) Lo fan Hi fan HH fan (1.1) (1.0) (0.9) (25) (30) (35) (40) Outdoor air temperature °F (°C) (2) Operating current performance chart Lo fan...
  • Page 41 Outdoor Unit CU-4KS24NBU Indoor Unit CS-KS18NB4UW × 1 Cooling Characteristics (RH : 46%, Indoor fan speed : High fan) (230V, 60Hz) (1) Low pressure performance chart (1.2) HH fan Lo fan Hi fan (1.1) (1.0) (0.9) (25) (30) (35) (40) Outdoor air temperature °F (°C) (2) Operating current performance chart Lo fan...
  • Page 42 5-1-3. Temperature Charts (CU-4KS31NBU) Outdoor Unit CU-4KS31NBU Indoor Unit CS-MKS7NKU × Cooling Characteristics (RH : 46%, Indoor fan speed : High fan) (230V, 60Hz) (1) Low pressure performance chart Lo fan Hi fan Hi fan HH fan (1.2) (1.0) (0.8) (0.6) (25) (30)
  • Page 43 Outdoor Unit CU-4KS31NBU Indoor Unit CS-MKS9NKU × 1 Cooling Characteristics (RH : 46%, Indoor fan speed : High fan) (230V, 60Hz) (1) Low pressure performance chart Lo fan Hi fan Hi fan HH fan (1.2) (1.0) (0.8) (0.6) (25) (30) (35) (40) Outdoor air temperature °F (°C)
  • Page 44 Outdoor Unit CU-4KS31NBU Indoor Unit CS-MKS12NKU × 1 Cooling Characteristics (RH : 46%, Indoor fan speed : High fan) (230V, 60Hz) (1) Low pressure performance chart Lo fan Hi fan Hi fan HH fan (1.2) (1.0) (0.8) (0.6) (25) (30) (35) (40) Outdoor air temperature °F (°C)
  • Page 45 Outdoor Unit CU-4KS31NBU Indoor Unit CS-MKS18NKU × 1 Cooling Characteristics (RH : 46%, Indoor fan speed : High fan) (230V, 60Hz) (1) Low pressure performance chart Lo fan Hi fan (1.2) (1.0) (0.8) (0.6) (25) (30) (35) (40) Outdoor air temperature °F (°C) (2) Operating current performance chart Lo fan Hi fan...
  • Page 46 Outdoor Unit CU-4KS31NBU Indoor Unit CS-MKS24NKU × 1 Cooling Characteristics (RH : 46%, Indoor fan speed : High fan) (230V, 60Hz) (1) Low pressure performance chart Lo fan Hi fan (1.2) (1.0) (0.8) (0.6) (25) (30) (35) (40) Outdoor air temperature °F (°C) (2) Operating current performance chart Lo fan Hi fan...
  • Page 47 Outdoor Unit CU-4KS31NBU Indoor Unit CS-MKS9NB4U × 1 Cooling Characteristics (RH : 46%, Indoor fan speed : High fan) (230V, 60Hz) (1) Low pressure performance chart Lo fan Hi fan Hi fan HH fan (1.2) (1.0) (0.8) (0.6) (25) (30) (35) (40) Outdoor air temperature °F (°C)
  • Page 48 Outdoor Unit CU-4KS31NBU Indoor Unit CS-MKS12NB4U × 1 Cooling Characteristics (RH : 46%, Indoor fan speed : High fan) (230V, 60Hz) (1) Low pressure performance chart Lo fan Hi fan Hi fan HH fan (1.2) (1.0) (0.8) (0.6) (25) (30) (35) (40) Outdoor air temperature °F (°C)
  • Page 49 Outdoor Unit CU-4KS31NBU Indoor Unit CS-KS18NB4UW × 1 Cooling Characteristics (RH : 46%, Indoor fan speed : High fan) (230V, 60Hz) (1) Low pressure performance chart Lo fan Hi fan (1.2) (1.0) (0.8) (0.6) (25) (30) (35) (40) Outdoor air temperature °F (°C) (2) Operating current performance chart Lo fan Hi fan...

  • Page 50: Cooling Capacity

    5-2. Cooling Capacity Outdoor Unit : CU-3KS19NBU Indoor Unit : CS-MKS9NKU × 3 Power Supply : 230V Single Phase 60Hz < Cooling Capacity > RATING CAPACITY: 18,800 BTU/h AIR FLOW RATE: 777 CFM INDOOR OUTDOOR ENT. TEMP. AMBIENT TEMP. (18.3) (23.9)
  • Page 51 Outdoor Unit : CU-3KS19NBU Indoor Unit : CS-MKS12NB4U × 3 Power Supply : 230V Single Phase 60Hz < Cooling Capacity > RATING CAPACITY: 18,300 BTU/h AIR FLOW RATE: 706 CFM INDOOR OUTDOOR ENT. TEMP. AMBIENT TEMP. (18.3) (23.9) (29.4) (35.0) (40.6)
  • Page 52 Outdoor Unit : CU-4KS24NBU × Indoor Unit : CS-MKS9NKU Power Supply : 230V Single Phase 60Hz < Cooling Capacity > RATING CAPACITY: 25,400 BTU/h AIR FLOW RATE: 777 CFM INDOOR OUTDOOR ENT. TEMP. AMBIENT TEMP. (18.3) (23.9) (29.4) (35.0) (40.6) (46.1) 25,520 24,880...
  • Page 53 Outdoor Unit : CU-4KS24NBU Indoor Unit : CS-KS18NB4UW + CS-MKS12NB4U + CS-MKS12NB4U Power Supply : 230V Single Phase 60Hz < Cooling Capacity > RATING CAPACITY: 24,800 BTU/h AIR FLOW RATE: 812 CFM INDOOR OUTDOOR ENT. TEMP. AMBIENT TEMP. (18.3) (23.9) (29.4) (35.0) (40.6)
  • Page 54 Outdoor Unit : CU-4KS31NBU × Indoor Unit : CS-MKS9NKU Power Supply : 230V Single Phase 60Hz < Cooling Capacity > RATING CAPACITY: 30,600 BTU/h AIR FLOW RATE: 1,036 CFM INDOOR OUTDOOR ENT. TEMP. AMBIENT TEMP. (18.3) (23.9) (29.4) (35.0) (40.6) (46.1) 30,850 29,770...
  • Page 55 Outdoor Unit : CU-4KS31NBU Indoor Unit : CS-MKS9NB4U × 4 Power Supply : 230V Single Phase 60Hz < Cooling Capacity > RATING CAPACITY: 28,600 BTU/h AIR FLOW RATE: 883 CFM INDOOR OUTDOOR ENT. TEMP. AMBIENT TEMP. (18.3) (23.9) (29.4) (35.0) (40.6) (46.1) 28,830...

  • Page 56: Cooling Capacity (Low Ambient)

    5-3. Cooling Capacity (Low Ambient) Outdoor Unit : CU-3KS19NBU Indoor Unit : CS-MKS9NKU × 3 Power Supply : 230V Single Phase 60Hz < Cooling Capacity (Low Ambient) > RATING CAPACITY: 18,800 BTU/h AIR FLOW RATE: 777 CFM INDOOR OUTDOOR ENT. TEMP.
  • Page 57 Outdoor Unit : CU-3KS19NBU Indoor Unit : CS-MKS12NB4U × 3 Power Supply : 230V Single Phase 60Hz < Cooling Capacity (Low Ambient) > RATING CAPACITY: 18,300 BTU/h AIR FLOW RATE: 706 CFM INDOOR OUTDOOR ENT. TEMP. AMBIENT TEMP. (-9.4) (-3.9) (1.7)
  • Page 58 Outdoor Unit : CU-4KS24NBU × Indoor Unit : CS-MKS9NKU Power Supply : 230V Single Phase 60Hz < Cooling Capacity (Low Ambient) > RATING CAPACITY: 25,400 BTU/h AIR FLOW RATE: 777 CFM INDOOR OUTDOOR ENT. TEMP. AMBIENT TEMP. (-9.4) (-3.9) (1.7) (7.2) (12.8) 25,470...
  • Page 59 Outdoor Unit : CU-4KS24NBU Indoor Unit : CS-KS18NB4UW + CS-MKS12NB4U + CS-MKS12NB4U Power Supply : 230V Single Phase 60Hz < Cooling Capacity (Low Ambient) > RATING CAPACITY: 24,800 BTU/h AIR FLOW RATE: 812 CFM INDOOR OUTDOOR ENT. TEMP. AMBIENT TEMP. (-9.4) (-3.9) (1.7)
  • Page 60 Outdoor Unit : CU-4KS31NBU × Indoor Unit : CS-MKS9NKU Power Supply : 230V Single Phase 60Hz < Cooling Capacity (Low Ambient) > RATING CAPACITY: 30,600 BTU/h AIR FLOW RATE: 1,036 CFM INDOOR OUTDOOR ENT. TEMP. AMBIENT TEMP. (-17.8) (-15.0) (-9.4) (-3.9) (1.7) (7.2)
  • Page 61 Outdoor Unit : CU-4KS31NBU Indoor Unit : CS-MKS9NB4U × 4 Power Supply : 230V Single Phase 60Hz < Cooling Capacity (Low Ambient) > RATING CAPACITY: 28,600 BTU/h AIR FLOW RATE: 883 CFM INDOOR OUTDOOR ENT. TEMP. AMBIENT TEMP. (-9.4) (-3.9) (1.7) (7.2) (12.8)

  • Page 62: Electrical Data

    6. ELECTRICAL DATA 6-1. Electric Wiring Diagrams Outdoor Unit CU-3KS19NBU 8FA2-5251-11800-1...
  • Page 63 Outdoor Unit CU-4KS24NBU 8FA2-5251-11600-1...
  • Page 64 Outdoor Unit CU-4KS31NBU 8FA2-5251-11400-1...

  • Page 65: Functions

    7. FUNCTIONS 7-1. Explanation of Functions NOTE The numerical values such as temperature, frequency, time and current in parentheses are an example of CU-4KS31NBU and the values are different from the other models. Control/conditions Unit operation Explanation INITIAL Breaker is ON. Power is supplied to the indoor and outdoor unit control circuits, however the unit remains stopped.
  • Page 66 Control/conditions Unit operation Explanation COOL The ON/OFF operation The operation lamp illuminates. The outdoor unit does not operate for 3 minutes button on the remote even after the breaker is turned ON. The indoor fan operates at the set fan speed. controller is pressed.
  • Page 67 (1/f fluctuation fan) Control/conditions Unit operation Explanation SENSOR The ON/OFF operation The operation lamp illuminates. The outdoor unit does not operate for 3 minutes button on the remote even after the breaker is turned ON. The indoor fan operates at the set fan speed. controller is pressed.
  • Page 68 < Low Ambient Cooling Operation > When the outdoor air temperature reaches 57.2 °F (14 °C ) or less during the cooling operation, the operation mode is switched to low ambient cooling operation. When the mode is switched from cooling opration to low ambient cooling operation, the compressor is stopped for 150 seconds temporarily.

  • Page 69: Protective Functions

    7-2. Protective Functions NOTE The numerical values such as temperature, frequency, time and current in parentheses are an example of CU-4KS31NBU and the values are different from the other models. 7-2-1. Current Control The operating current may rise as a result of causes including increasing cooling loads or decreases in power voltage.
  • Page 70 (2) Current control The operating frequency upper limits shown in the figure below are established for frequency reduction and increase-prohibit. Current(A) Example of operation during cooling Trip Hz reduction Hz reduction Hz increase prohibit Hz increase prohibit Hz reduction (16) Hz increase prohibit (15.6) Frequency (Hz)

  • Page 71: Troubleshooting (Before Calling For Service)

    8. TROUBLESHOOTING (BEFORE CALLING FOR SERVICE) 8-1. Precautions before Performing Inspection or Repair Both the indoor unit and outdoor unit include electronic control circuits. Be sure to pay attention to the following before inspecting or repairing the outdoor-side electronic circuits. High-capacity electrolytic capacitors are used inside the outdoor unit controller (inverter).

  • Page 72: Trouble Diagnosis By Error Monitor Lamps

    8-2. Trouble Diagnosis by Error Monitor Lamps To prevent electric shock, do not inspect or repair until the Power Lamp on Warning the P.C.Board is turned off. 8-2-1. Location of the Error Monitor Lamps Remove the top plate of outdoor unit and the cover of Electrical Component Box. The Power Lamp and Error Monitor Lamps are located on the P.C.Board of Electrical Component Box.

  • Page 73: Checking The Outdoor System

    8-3. Checking the Outdoor System 8-3-1. Checking the outdoor unit Work procedure Check items (unit operation) • Apply 220 V AC between terminals L1 and L2 on the • The LED (red) on the control board must illuminate. outdoor unit terminal plate. •...

  • Page 74: Trouble Diagnosis Of Each Part

    8-4. Trouble Diagnosis of Each Part 8-4-1. Problems of Each Part and Inspection Points For details about the inspection points, refer to the Inspection Points for Each Part. Indoor unit Outdoor unit Others Problems No. of Inspection Points for Each part Inspection points Self-Diagnostics check...
  • Page 75 Indoor unit Outdoor unit Others Problems No. of Inspection Points for Each part Inspection points Breaker Refrigerant gas pressure 8-4-2. Inspection Points for Each Part (1) Outdoor control circuit board Refer to 8-3-1. Checking the outdoor unit. Do not remove or insert the outdoor control circuit board connector when power is being supplied to it. NOTE (The controller will be damaged.) (2) Fuse...
  • Page 76 10 to 20 seconds for No voltage on circuit board Voltage varies each point. Model No. Sequence CU-3KS19NBU CU-4KS24NBU CU-4KS31NBU Check the coil resistance. Check the resistance between the gray lead Check the illumination wire and the other wires.
  • Page 77 (7) Branch tubing temperature sensor Check that the sensor is securely contained in the thermostat holder. (8) Breaker Check whether or not the breaker has been tripped. Check that the breakers and fuses used are of the specified capacity. Check that the breaker and its line are exclusive for A/C use. (9) Refrigerant gas pressure Start a COOL test run, and messure the temperatures of the A/C intake air and discharge air.

  • Page 78: Trouble Diagnosis Of Fan Motor

    8-5. Trouble Diagnosis of Fan Motor This outdoor DC fan motor contains an internal control PCB. Therefore, it is not possible to measure the coil resistance, and the following procedure should be used to check the motor. Perform the trouble diagnosis by Test Run mode described on Installation Instructions of indoor unit. Important: (A) Turn OFF the power before connecting or disconnecting the motor connectors.

  • Page 79: Refrigerant R410A: Special Precautions When Servicing Unit

    9. REFRIGERANT R410A: SPECIAL PRECAUTIONS WHEN SERVICING UNIT 9-1. Characteristics of New Refrigerant R410A 9-1-1. What is New Refrigerant R410A? R410A is a new refrigerant that contains two types of pseudo-non-azeotropic refrigerant mixture. Its refrigeration capacity and energy efficiency are about the same level as the conventional refrigerant, R22. 9-1-2.

  • Page 80: Checklist Before Servicing

    9-2. Checklist before Servicing Use a clutch-type flare tool for R410A or the conventional flare tool. Note that sizes of the resultant flares differ between these two tools. Where a conventional flare tool is used, make sure to observe A Specification (amount of extrusion) by using the flare spacer.

  • Page 81: Tools Specifically For R410A

    9-3. Tools Specifically for R410A For servicing, use the following tools for R410A Tool Distinction Tool Name Gauge manifold Charging hose Gas leak detector Refrigerant cylinder Charging cylinder Refrigerant recovery unit Vacuum pump with anti-reverse flow (*1) Tools specifically for R410A (Solenoid valve-installed type, which prevents oil from flowing back into the unit when the power is off, is recommended.) Vacuum pump (*2)...can be used if the following adapter is attached.

  • Page 82: In Case Of Compressor Malfunction

    9-5. In Case of Compressor Malfunction Should the compressor malfunction, be sure to make the switch to a replacement CAUTION compressor as quickly as possible. Use only the tools indicated exclusively for R410A. See "9-3. Tools Specifically for R410A." 9-5-1. Procedure for Replacing Compressor (1) Recovering refrigerant Any remaining refrigerant inside the unit should not be released to the atmosphere, but recovered using the...
  • Page 83 (5) Recharging Configuration and characteristics of cylinders Be sure to charge the specified amount of Valve refrigerant in liquid state using the service port of the wide tube service valve. The proper amount is listed on the unit's nameplate. When the entire amount cannot be charged all at once, charge gradually while operating the unit in Cooling Operation.

  • Page 84: In Case Refrigerant Is Leaking

    9-6. In Case Refrigerant is Leaking Never attempt to charge additional refrigerant when refrigerant has been leaking CAUTION from the unit. Follow the procedure described below to locate points of leaks and carry out repairs, then recharge the refrigerant. (1) Detecting Leaks Use the detector for R410A to locate refrigerant leak points.

  • Page 85: Charging Additional Refrigerant

    9-7. Charging Additional Refrigerant 9-7-1. When Tubes are Extended Observe the proper amount of refrigerant as stated in this service manual or the installation manual that came with the indoor unit. Charge additional refrigerant in liquid state only. Never charge additional refrigerant if refrigerant is leaking from the unit. Follow CAUTION instructions given in "9-6.

  • Page 86: Appendix Ainstallation Instructions

    APPENDIX A INSTALLATION INSTRUCTIONS CU-3KS19NBU CU-4KS24NBU CU-4KS31NBU (852-6-4190-581-00-1)

  • Page 87: Installation Instructions

    1-5. Additional Materials Required for Installation Model No. INSTALLATION SITE SELECTION ....5 Indoor Unit Outdoor Unit 2-1. Indoor Unit CS-MKS7NKU CU-3KS19NBU 2-2. Connecting Indoor Units CS-MKS9NKU CU-4KS24NBU 2-3. Outdoor Unit CS-MKS12NKU CU-4KS31NBU 2-4. Baffle Plate for the Outdoor Unit 2-5.

  • Page 88: Important

    IMPORTANT! When Transporting Please Read Before Starting Be careful when picking up and moving the indoor and out- door units. Get a partner to help, and bend your knees when This air conditioning system meets strict safety and operating lifting to reduce strain on your back. Sharp edges or thin alu- standards.
  • Page 89 Others the flare and union tubes before connecting them, then CAUTION tighten the nut with a torque wrench for a leak-free connection. the refrigeration system. Escaped refrigerant gas, on contact with fire or heat, can produce dangerously or re-installation, and while repairing refrigeration parts. toxic gas.

  • Page 90: General

    (1/2" 3/8") cable and tube CU-4KS31NBU Packed in the outdoor unit. Reducer CU-3KS19NBU (3/8" 1/2") 1-3. Optional Copper Tubing Kit Foamed polyethylene insulation for the specified copper tubes as required to precise length of tubing. Copper tubing for connecting the outdoor unit to the...

  • Page 91: Installation Site Selection

    2. Installation Site Selection Indoor unit 2-1. Indoor Unit To prevent abnormal heat generation WARNING and the possibility of fire, do not place obstacles, enclosures and grilles in front of or surrounding the air conditioner in a way that may block air flow.
  • Page 92 (L1+L2+L3) or (H1, H2, H3, H4) Refrigerant Per Unit (L1+L2+L3) or (L1+L2+L3+L4) (ft.) (oz./ft.) (ft.) (L1+L2+L3+L4) (ft.) (ft.) CU-3KS19NBU 150 (L1+L2+L3) 150 (L1+L2+L3) — CU-4KS24NBU 150 (L1+L2+L3+L4) 200 (L1+L2+L3+L4) 0.22 CU-4KS31NBU 150 (L1+L2+L3+L4) 230 (L1+L2+L3+L4) 0.22 * If total tubing length becomes 150 to 200 ft. (Max.) or 150 to 230 ft. (Max.), charge additional refrigerant (R410A) by 0.22 oz./ft.

  • Page 93: Connecting Indoor Units

    Figures (4a) – (4k) show the different types of indoor unit connections, including the use of a reducer. To select the required indoor unit to be connected, refer to the Combination Table that was included in the outdoor unit package. (1) Connecting indoor unit for CU-3KS19NBU Outdoor unit Indoor unit 3/8"(9.52mm)
  • Page 94 Outdoor unit Indoor unit 1/2"(12.70mm) (CS-MKS18NKU) (CS-KS18NB4UW) 1/2"(12.70mm) 1/4"(6.35mm) 3/8"(9.52mm) (CS-MKS7NKU,CS-MKS9NKU,CS-MKS12NKU) (CS-MKS9NB4U,CS-MKS12NB4U) 3/8"(9.52mm) 1/4"(6.35mm) 3/8"(9.52mm) (CS-MKS7NKU,CS-MKS9NKU,CS-MKS12NKU) (CS-MKS9NB4U,CS-MKS12NB4U) 3/8"(9.52mm) 1/4"(6.35mm) 3/8"(9.52mm) (CS-MKS7NKU,CS-MKS9NKU,CS-MKS12NKU) (CS-MKS9NB4U,CS-MKS12NB4U) 3/8"(9.52mm) 1/4"(6.35mm) Fig. 4d (1/2"(12.70mm) 5/8"(15.88mm)) Locally purchased Flare 1/2"(12.70mm) Union 5/8"(15.88mm) Outdoor unit Indoor unit 5/8"(15.88mm) (CS-MKS24NKU) 1/2"(12.70mm) 1/4"(6.35mm) 3/8"(9.52mm)
  • Page 95 (3) Connecting indoor unit for CU-4KS31NBU (1/2"(12.70mm) 3/8"(9.52mm)) Supplied Reducer Flare 1/2"(12.70mm) Union 3/8"(9.52mm) Outdoor unit Indoor unit 3/8"(9.52mm) (CS-MKS7NKU,CS-MKS9NKU,CS-MKS12NKU) (CS-MKS9NB4U,CS-MKS12NB4U) 1/2"(12.70mm) 1/4"(6.35mm) 3/8"(9.52mm) (CS-MKS7NKU,CS-MKS9NKU,CS-MKS12NKU) (CS-MKS9NB4U,CS-MKS12NB4U) 1/2"(12.70mm) 1/4"(6.35mm) 3/8"(9.52mm) (CS-MKS7NKU,CS-MKS9NKU,CS-MKS12NKU) (CS-MKS9NB4U,CS-MKS12NB4U) 3/8"(9.52mm) 1/4"(6.35mm) 3/8"(9.52mm) (CS-MKS7NKU,CS-MKS9NKU,CS-MKS12NKU) (CS-MKS9NB4U,CS-MKS12NB4U) 3/8"(9.52mm) 1/4"(6.35mm) Fig. 4g (1/2"(12.70mm 3/8"(9.52mm)) Supplied Reducer Flare 1/2"(12.70mm)
  • Page 96 (1/2"(12.70mm) 5/8"(15.88mm))Locally purchased Flare 1/2"(12.70mm) Union 5/8"(15.88mm) Outdoor unit Indoor unit 5/8"(15.88mm) (CS-MKS24NKU) 1/2"(12.70mm) 1/4"(6.35mm) 3/8"(9.52mm) (CS-MKS7NKU,CS-MKS9NKU,CS-MKS12NKU) (CS-MKS9NB4U,CS-MKS12NB4U) 1/2"(12.70mm) 1/4"(6.35mm) 3/8"(9.52mm) (CS-MKS7NKU,CS-MKS9NKU,CS-MKS12NKU) (CS-MKS9NB4U,CS-MKS12NB4U) 3/8"(9.52mm) 1/4"(6.35mm) 3/8"(9.52mm) (CS-MKS7NKU,CS-MKS9NKU,CS-MKS12NKU) (CS-MKS9NB4U,CS-MKS12NB4U) 3/8"(9.52mm) 1/4"(6.35mm) Flare 1/2"(12.70mm) Union 3/8"(9.52mm) (1/2"(12.70mm) 3/8"(9.52mm))Supplied Reducer Fig. 4j (1/2"(12.70mm) 5/8"(15.88mm)) Locally purchased Flare 1/2"(12.70mm) Union 5/8"(15.88mm)

  • Page 97: Outdoor Unit

    2-3. Outdoor Unit Exhaust fan AVOID: Hot air heat sources, exhaust fans, etc. (Fig. 5a) Heat source damp, humid or uneven locations. Outdoor unit Obstacle above choose a place as cool as possible. Min. choose a place that is well ventilated. Min.
  • Page 98 Dimensions Model (inch) 25-3/16 25/32 1-31/32 10-5/8 10-5/8 25/64 25/32 19/32 25-7/8 19/64 25/64 5-29/32 25/32 25/32 CU-3KS19NBU, CU-4KS24NBU (mm) (inch) 25-3/16 25/32 1-3/8 30-29/32 13-25/32 13-25/32 25/64 25/32 19/32 31-25/32 19/64 25/64 5-29/32 25/32 25/32 CU-4KS31NBU (mm) For Air Discharge...
  • Page 99 (3) Installation procedure 1. Air Intake Baffle 2. Air Discharge Baffle 1. Remove the panels front, top, side L and R from the (1) Left side unit and drill 4 holes of ø1/4 inch (6.5 mm) at the 1. Remove the top panel from the unit. prescribed positions.

  • Page 100: Outer Dimensions Of Outdoor Unit

    2-5. Outer Dimensions of Outdoor Unit (1) CU-3KS19NBU 23-15/16 5-11/32 15/32 35-7/16 (900) 2-29/32 Service valve on narrow tube side (Outer diameter 1/4"( 6.35 )) Service valve on wide tube side (Outer diameter 3/8"( 9.52 )) 2-1/32 4-1/2 1-13/16 2-1/16 Fig.

  • Page 101: Diagram Of Outdoor Unit Installation

    Diagram of Outdoor Unit Installation 2-6. Never install only a single indoor unit. Ceiling-mounted Wall-mounted types cassette types Indoor unit D Indoor unit D Be sure to connect indoor and outdoor units only in combinations that are listed in the catalog or in the combination table that was provided with the outdoor unit.

  • Page 102: Installation Process

    3. Installation Process Embedding the Tubing and Wiring 3-1. Do not connect tubes to locations that are embedded. Be sure to bind refrigerant tubing and inter-unit cables together with vinyl tape. The power cable must be obtained on-site. (#12: Less than 85 ft.) # ...

  • Page 103: Caution Before Connecting Tubes Tightly

    NOTE Copper tubing When reaming, hold the tube end downward and be sure that no copper scraps fall into the tube. (Fig. 9) (3) Remove the flare nut from the unit and be sure to mount Reamer it on the copper tube. (4) Make a flare at the end of copper tube with a flare tool.* (Figs.

  • Page 104: Insulation Of Refrigerant Tubing

    Torque wrench Be sure to match refrigerant CAUTION tubing and electric wiring between indoor and outdoor Spanner Indoor unit units. Outdoor unit Fig. 15 3-6. Insulation of Refrigerant Tubing Insulation IMPORTANT Thickness: min. 5/16" Min. To prevent heat loss and wet floors due to dripping of con- (8 mm) 5/16"...

  • Page 105: Taping The Tubes

    3-7. Taping the Tubes After a tube has been insulated, CAUTION never try to bend it into a narrow curve, as this may cause the tube Clamp to break or crack. nsulated tubes (1) At this time, the 2 refrigerant tubes (and electrical wire if local codes permit) should be taped together with armoring tape.
  • Page 106 Stopper Cap tightening torque: 170 – 215 lbs·in Spindle Perform the air purge for tubes A, B, C, and D. Use the same (200 – 250 kgf·cm) Service port procedures for all tubes. (Tighten by hand, then Screw diameter: 1/2 use a wrench to turn (1) Check that each tube (both narrow and wide tubes) UNF 20 threads...

  • Page 107: Pump Down

    (11) Replace the flare nut on the wide tube service port and fasten the flare nut securely with an adjustable wrench or box wrench. Next, mount the valve cap and tighten it with a torque wrench (the cap needs to be tightened with the torque of 180 lbs·in (200 kgf·cm)).

  • Page 108: Wiring Instructions

    National Electric Code: ANSI/NFPA70. Table 6 Max. Power Line Length (ft.) Max. Control Line Length (ft.) Fuse (B) (C) Model Circuit Capacity (#12) (#14) CU-3KS19NBU 85 (Max.) 82 (Max.) 15 A CU-4KS24NBU 85 (Max.) 82 (Max.) 20 A CU-4KS31NBU 85 (Max.) 100 (Max.)

  • Page 109: Wiring System Diagram

    Always comply with national and local code requirements. indoor and outdoor units. Electrical noise may affect the operation. 5-3. Wiring System Diagram 3 indoor units with CU-3KS19NBU 4 indoor units with CU-4KS24NBU, CU-4KS31NBU Disconnect Disconnect switch switch...

  • Page 110: How To Connect Wiring To The Terminal

    5-4. How to Connect Wiring to the Terminal Loose wiring may cause the WARNING terminal to overheat or result in unit malfunction. A fire hazard may also exist. There- fore, be sure all wiring is tightly connected. When connecting each power wire to the corresponding terminal, follow the instructions “How to connect wiring 9/32"...

  • Page 111: Wiring Instructions For The Outdoor Unit

    5-5. Wiring Instructions for the Outdoor Unit CAUTION Be sure to correctly align inter-unit cables A, B, C and D. Outdoor unit Terminal board Power supply 1 2 3 4 5 6 7 8 9 10 11 12 (conduit) Power: Single-phase, 230/208VAC 60HZ Power breaker...

  • Page 112: Test Run

    Regulations on wire size differ from locality to locality. For Lock nut Cabinet field wiring requirements, please refer to your local electri- cal codes. Make sure that the installation fully complies with all local and national regulations. (1) Remove access panel “C”. (Fig. 32) (2) Connect the inter-unit and power supply line accord- ing to the drawing on the panel side.

  • Page 113: Connecting A Home Automation Device

    7. Connecting a Home Automation Device The HA (white) 4P terminal is located on the indoor unit PCB. If a HA device will be used, connect it to this terminal. 8. Installation Check Sheet The strength of the installation location is sufficient to support the air conditioner weight. The indoor and outdoor units are installed level and vertically.
  • Page 114 DC1111-0...

This manual is also suitable for:

Cu-4ks24nbuCu-4ks31nbu

Table of Contents