1. Manuals
  2. Brands
  3. Hitachi Manuals
  4. Air Conditioner
  5. RAS-18CH7
  6. Service manual

Hitachi RAS-18CH7 Service Manual

Hide thumbs Also See for RAS-18CH7:
Table of Contents

Advertisement

Quick Links

Download this manual
SERVICE MANUAL
TECHNICAL INFORMATION
FOR SERVICE PERSONNEL ONLY
SPECIFICATIONS
TYPE
MODEL
POWER SOURCE
TOTAL INPUT
TOTAL AMPERES
COOLING
CAPACITY
TOTAL INPUT
TOTAL AMPERES
HEATING
CAPACITY
DIMENSIONS
(mm)
NET WEIGHT
SPECIFICATIONS AND PARTS ARE SUBJECT TO CHANGE FOR IMPROVEMENT
ROOM AIR CONDITIONER
DECEMBER 2006
RAS-18CH7
RAS-24CH7
RAC-18CH7
RAC-24CH7
INDOOR UNIT
RAS-18CH7
1 Ø, 50 Hz, 220 - 240V
(W)
(A)
(kW)
(B.T.U./h)
(W)
(A)
(kW)
(B.T.U./h)
W
1030
H
295
191
D
(kg)
11
INDOOR UNIT + OUTDOOR UNIT
Refrigeration & Air-Conditioning Division
PM
RAS-18CH7/RAC-18CH7
RAS-24CH7/RAC-24CH7
REFER TO THE FOUNDATION MANUAL
SPECIFICATIONS ----------------------------------------------------- 4
HOW TO USE ---------------------------------------------------------- 7
MAIN PARTS COMPONENT ------------------------------------- 33
WIRING DIAGRAM -------------------------------------------------- 35
CIRCUIT DIAGRAM ------------------------------------------------- 37
BLOCK DIAGRAM --------------------------------------------------- 41
BASIC MODE --------------------------------------------------------- 43
REFRIGERATING CYCLE DIAGRAM ------------------------- 49
AUTO SWING FUNCTION ---------------------------------------- 55
TROUBLE SHOOTING --------------------------------------------- 62
PARTS LIST AND DIAGRAM ------------------------------------ 65
(WALL TYPE)
OUTDOOR UNIT
RAC-18CH7
1680 - 1730
7.8 - 7.40
5.10
17,410
1700 - 1750
8.00 - 7.50
5.7
19,460
850
650
298
55
NO. 0346E
CONTENTS
INDOOR UNIT
OUTDOOR UNIT
RAS-24CH7
RAC-24CH7
1 Ø, 50 Hz, 220-240V
2270-2400
10.9-10.5
6.30
21,500
2370-2400
11.20-10.40
7.05
24,060
1030
850
295
650
191
298
12
50
After installation

Advertisement

Table of Contents
loading

Related Manuals for Hitachi RAS-18CH7

Summary of Contents for Hitachi RAS-18CH7

  • Page 1: Table Of Contents

    NO. 0346E RAS-18CH7/RAC-18CH7 RAS-24CH7/RAC-24CH7 SERVICE MANUAL TECHNICAL INFORMATION REFER TO THE FOUNDATION MANUAL FOR SERVICE PERSONNEL ONLY CONTENTS SPECIFICATIONS ----------------------------------------------------- 4 HOW TO USE ---------------------------------------------------------- 7 CONSTRUCTION AND DIMENSIONAL DIAGRAM ------- 31 MAIN PARTS COMPONENT ------------------------------------- 33 WIRING DIAGRAM -------------------------------------------------- 35...
  • Page 2 SAFETY DURING REPAIR WORK 1. In order to disassemble and repair the unit in question, be sure to disconnect the power cord plug from the power outlet before starting the work. 2. If it is necessary to replace any parts, they should be replaced with respective genuine parts for the unit, and the replacement must be effected in correct manner according to the instructions in the Service Manual of the unit.
  • Page 3 WORKING STANDARDS FOR PREVENTING BREAKAGE OF SEMICONDUCTORS 1. Scope The standards provide for items to be generally observed in carrying and handling semiconductors in relative manufacturers during maintenance and handling thereof. (They apply the same to handling of abnormal goods such as rejected goods being returned). 2.
  • Page 4 (6) Use a three wire type soldering iron including a grounding wire. Metal plate (of aluminium, stainless steel, etc.) Working table Resistor of 1 M (1/2W) Staple Earth wire Bare copper wire (for body earth) Fig. 3. Grounding of the working table Soldering iron Grounding wire...
  • Page 5 CAUTION In quiet or stopping operation, slight flowing noise of refrigerant in the refrigerating cycle is heard occasionally, but this noise is not abnormal for the operation. When it thunders near by, it is recommended to stop the operation and to disconnect the power cord plug from the power outlet for safety.

  • Page 6: Specifications

    SPECIFICATIONS MODEL RAS-18CH7 RAC-18CH7 20 W FAN MOTOR 40 W FAN MOTOR CAPACITOR 2.5 F,450V FAN MOTOR PROTECTOR YES (INTERNAL) COMPRESSOR – SHX33SC4-U COMPRESSOR MOTOR CAPACITOR 50 F, 440VAC OVERLOAD PROTECTOR YES (INTERNAL) OVERHEAT PROTECTOR YES (INTERNAL) FUSE (MICRO COMPUTER CIRCUIT) 3.15A...
  • Page 7 SPECIFICATIONS MODEL RAS-24CH7 RAC-24CH7 20 W FAN MOTOR 40 W FAN MOTOR CAPACITOR 2.5 F,450V FAN MOTOR PROTECTOR YES (INTERNAL) COMPRESSOR – SHV33YC6-U COMPRESSOR MOTOR CAPACITOR 50 F, 450VAC OVERLOAD PROTECTOR YES (INTERNAL) OVERHEAT PROTECTOR YES (INTERNAL) FUSE (MICRO COMPUTER CIRCUIT) 3.15A POWER RELAY POWER SWITCH...
  • Page 8 Figure showing the installation of Indoor anf Outdoor unit The installation height of indoor unit must be 2.3m or more. CAUTION above 50mm above 100mm above 100mm 2,300mm or more The indoor piping should be insulated with the enclosed Plug insulation pipe.
  • Page 9 SAFETY PRECAUTION Please read the “Safety Precaution” carefully before operating the unit to ensure correct usage of the unit. Pay special attention to signs of “ Warning” and “ Caution”. The “Warning” section contains matters which, if not observed strictly, may cause death or serious injury. The “Caution” section contains matters which may result in serious consequences if not observed properly.
  • Page 10 PRECAUTIONS DURING OPERATION The product shall be operated under the manufacturer specification and not for any other intended use. Do not attempt to operate the unit with wet hands, this could cause fatal accident. When operating the unit with burning equipments, regularly ventilate the room to avoid oxygen insufficiency.
  • Page 11 Don’t close drain outlet portion in chilly area so as not to freeze these. MODEL NAME AND DIMENSIONS MODEL WIDTH (mm) HEIGHT (mm) DEPTH (mm) RAS-18CH7 / RAS-24CH7 1030 RAC-18CH7 / RAC-24CH7 – 9 –...
  • Page 12 This lamp lights during operation. The OPERATION LAMP flashes in the following cases during heating. (1) During preheating HITACHI For about 2–3 minutes after starting up. (2) During defrosting Defrosting will be performed about once an hour when frost forms on the heat exchanger of the outdoor unit, for 5–10 minutes each time.
  • Page 13 NAMES AND FUNCTIONS OF REMOTE CONTROL UNIT REMOTE CONTROLLER This controls the operation of the indoor unit. The range of control is about 7 meters. If indoor lighting is controlled electronically, the range of control may be shorter. This unit can be fixed on a wall using the fixture provided. Before fixing it, make sure the indoor unit can be controlled from the remote controller.
  • Page 14 AUTOMATIC OPERATION The device will automatically determine the mode of operation, HEAT, COOL or DEHUMIDIFY depending on the initial room temperature. The selected mode of operation will not change when the room temperature varies. Press the FUNCTION selector so that the display indicates the (AUTO) mode of operation.
  • Page 15 HEATING OPERATION Use the device for heating when the outdoor temperature is under 21°C. When it is too warm (over 21°C), the heating function may not work in order to protect the device. Press the FUNCTION selector so that the display indicates (HEAT).
  • Page 16 DEHUMIDIFYING OPERATION Use the device for dehumidifying when the room temperature is over 16°C. When it is under 15°C, the dehumidifying function will not work. Press the FUNCTION selector so that the display indicates (DEHUMIDIFY). ˚ The FAN SPEED is set at LOW automatically. The FAN SPEED button does not work.
  • Page 17 COOLING OPERATION Use the device for cooling when the outdoor temperature is 22-39°C. If indoor humidity is very high (80%), some dew may form on the air outlet grille of the indoor unit. Press the FUNCTION selector so that the display indicates (COOL).
  • Page 18 FAN OPERATION You can use the device simply as an air circulator. Use this function to dry the interior of the indoor unit at the end of summer. Press the FUNCTION selector so that the display indicates (FAN). Press the (FAN SPEED) button.* START Press the...
  • Page 19 HOW TO SET THE SLEEP TIMER Set the current time at first if it is not set before (see the pages for setting the current time). Press the (SLEEP) button, and the display changes as shown below. Mode Indication 1 hour 2 hours 3 hours 7 hours...
  • Page 20 HOW TO SET THE TIMER Time, Day, Month Set the current month and TIME, DAY, day with the TIMER control After you change the MONTH button. batteries; (current time, day, month) OFF TIMER RESET ON TIMER OFF-Timer Press the (OFF-TIMER) button.
  • Page 21 Set the current time with the Press the (TIME) button again. Press the TIMER control button. The time indication starts lighting (TIME) button. instead of flashing. The time indication will disappear automatically in 10 second. To check the current time setting, press the (TIME) button twice.
  • Page 22 Explanation of the sleep timer The device will control the FAN SPEED and room temperature automatically so as to be quiet and good for people’s health. You can set the sleep timer to turn off after 1, 2, 3 or 7 hours. The FAN SPEED and room temperature will be controlled as shown below.
  • Page 23 ADJUSTING THE AIR DEFLECTOR Adjustment of the conditioned air in the upward and downward directions. The horizontal air deflector is automatically set to the proper angle suitable for each operation. The deflector can be swung RESET up and down continuously and also set to the desired angle using the “...
  • Page 24 HOW TO EXCHANGE THE BATTERIES IN THE REMOTE CONTROLLER Remove the cover as shown in the figure and take out the Push and pull to the old batteries. direction of arrow Install the new batteries. The direction of the batteries should match the marks in the case.
  • Page 25 THE IDEAL WAYS OF OPERATION Suitable Room Temperature Install curtain or blinds Warning It is possible to Freezing temperature reduce heat is bad for health and a entering the waste of electric power. room through windows. Ventilation Effective Usage Of Timer At night, please use the “OFF or ON timer Caution operation mode”, together with your wake up...
  • Page 26 FOR USER’S INFORMATION The Air Conditioner And The Heat Source In The Room Caution If the amount of heat in the room is above the cooling capability of the air conditioner (for example: more people entering the room, using heating equipments and etc.), the preset room temperature cannot be achieved.
  • Page 27 ATTACHING THE AIR CLEANSING FILTERS CAUTION Cleaning and maintenance must be carried out only by qualified service personal. Before cleaning, stop operation and switch off the power supply. Open the front panel. Pull up the front panel by holding it at both sides with both hands.
  • Page 28 MAINTENANCE CAUTION Cleaning and maintenance must be carried out only by qualified service personal. Before cleaning, stop operation and switch off the power supply. AIR FILTER Clean the air filter, as it removes dust inside the room. In case the air filter is full of dust, the air flow will decrease and the cooling capacity will be reduced.
  • Page 29 Washable Front Panel Remove the front panel and wash with clean water. Wash it with a soft sponge. After using neutral detergent, wash thoroughly with clean water. When front panel is not removed, wipe it with a soft dry cloth. Wipe the remote controller thoroughly with a soft dry cloth.
  • Page 30 CAUTION Cleaning and maintenance must be carried out only by qualified service personal. Before cleaning, stop operation and switch off the power supply. 3. MAINTENANCE AT BEGINNING OF LONG OFF PERIOD Run the unit by setting the operation mode to (COOL), the temperature to 32°C and the fan speed to HI for about half a day on a fine day, and dry the whole of the unit.
  • Page 31 AFTER SALE SERVICE AND WARRANTY WHEN ASKING FOR SERVICE, CHECK THE FOLLOWING POINTS. CONDITION CHECK THE FOLLOWING POINTS Is the fuse all right? Is the voltage extremely high or low? When it does not operate Is the circuit breaker “ON”? Was the air filter cleaned? Does sunlight fall directly on the outdoor unit? Is the air flow of the outdoor unit obstructed?
  • Page 32 Please note: On switching on the equipment, particularly when the room light is dimmed, a slight brightness fluctuation may occur. This is of no consequence. The conditions of the local Power Supply Companies are to be observed. Note Avoid to use the room air conditioner for cooling operation when the outside temperature is below 21°C (70°F).

  • Page 33: Construction And Dimensional Diagram

    CONSTRUCTION AND DIMENSIONAL DIAGRAM MODEL RAS-18CH7/RAS-24CH7 1019 Top air suction grille 1030 Front cover Vertical deflector Discharge grille Horizontal deflector About View from back (Pipe lead-out) 17.5 120.5 When piping is drawn horizontally, exchange the drain hose for the drain cap...
  • Page 34 MODEL RAC-18CH7/RAC-24CH7 Handle Handle Air suction Air outlet grille Holes for anchor bolt (2-ø12) More than More than Fixing hole Service space Notch for anchor bolt (2-ø12 Notchs) Note: 1. 200mm or more servicing space is required above the outdoor unit. –...

  • Page 35: Main Parts Component

    MAIN PARTS COMPONENT THERMOSTAT (Room Temperature Thermistor) Thermostat Specifications MODEL RAS-18CH7 / RAS-24CH7 THERMOSTAT MODEL OPERATION COOL HEAT 17.6 (63.7) 19.6 (67.3) INDICATION 17.3 (63.1) 19.3 (66.7) TEMPERATURE °C 25.6 (78.1) 27.6 (81.7) INDICATION 25.3 (77.5) 27.3 (81.1) 33.6 (92.5) 35.6 (96.1)
  • Page 36 COMPRESSOR MOTOR Compressor Motor Specifications MODEL RAC-18CH7 RAC-24CH7 COMPRESSOR MODEL SHX33SC4-U SHV33YC6-U PHASE SINGLE RATED VOLTAGE 220 ~ 240V RATED FREQUENCY 50 Hz 45 A 45 A LOCKED ROTOR CURRENT POLE NUMBER WHITE PROTECTOR ORANGE CONNECTION CAPACITOR 20°C RM = 1.47 RM = 1.520 (68°F) RA = 2.88...
  • Page 37 – 35 –...
  • Page 38 – 36 –...

  • Page 39: Circuit Diagram

    CIRCUIT DIAGRAM Remote Control Key matrix table Output Input Door open Start/Stop Operation selection Fan speed selection Automatic swing Door shut Start/Stop Super silent cooling – – present time Door open On timer Hour up Hour down • Door shut –...

  • Page 40: Printed Wiring Board Location Diagram

    PRINTED WIRING BOARD LOCATION DIAGRAM MODEL RAS-18CH7 / RAS-24CH7 – 39 –...
  • Page 41 – 41 –...

  • Page 42: Basic Mode

    BASIC MODE MODEL RAS-18CH7/RAC-18CH7, RAS-24CH7/RAC-24CH7 Operation mode Cooling Sensor dehumidification Heating Automatic Control function Start/stop button, Start/stop button Operation lamp basic mode Start/stop button Reservation TEMPERATURE OF INDOOR HEAT EXCHANGER THERMISTOR Cancel Operation lamp OFF timer Timer lamp Timer memory...
  • Page 43 Operation mode Cooling Sensor dehumidification Heating Automatic Control function • Sleep operation is executed 5 deg down for each operation mode. Set circulation velocity LO (sleep operation) Set circulation temperature velocity 60 minutes LO (sleep operation) Table 1 Specifications Other detailed specifications 2 deg up Start/stop switch temperature...
  • Page 44 Table 1 Specifications (2) Compensation continuously occurs, and for the advance Item RAS-18CH7/RAS-24CH7 time, the temperature difference between The “Attained” state is monitored and a “Not attained” check is the set temperature without sleep shift Automatic done to revise the compensation time (HT).

  • Page 45: Refrigerating Cycle Diagram

    REFRIGERATING CYCLE DIAGRAM MODEL RAS-18CH7/RAC-18CH7 – 49 –...
  • Page 46 REFRIGERATING CYCLE DIAGRAM MODEL RAS-24CH7/RAC-24CH7 COOLING, DEHUMIDIFYING, DEFROSTING SUCTION TANK INDOOR UNIT OUTDOOR UNIT SERVICE VALVE SINGLE-ENDED UNION (5/8) REVERSING VALVE CAPILLARY SERVICE VALVE CHECKVALVE CAPILLARY STRAINER SINGLE-ENDED UNION STRAINER CHARGING PIPE SUCTION HEATING TANK INDOOR UNIT SERVICE VALVE SINGLE-ENDED OUTDOOR UNIT UNION (5/8) REVERSING...

  • Page 47: Description Of Main Circuit Operation

    DESCRIPTION OF MAIN CIRCUIT OPERATION 1. ON / OFF The “ON / OFF” and “Timer reserve button” and “Sleeping” function independently. Their operations are shown in Fig. 1-1. Start Stop Start ON/OFF button Timer reserve button (Sleeping) When OFF timer (sleeping) is set Operation lamp...
  • Page 48 2. Reset Circuit Micro computer (AX-3T3) Q512 Q511 C512 DC12V Line DC5V Line Base POWER ON POWER OFF Micro computer Pin 26 The reset circuit is used to reset the program to its initial settings when the power is turned on or when the power is recovered after a power failure.
  • Page 49 3. Buzzer Circuit Micro computer (AX-3T3) BUZZER When the buzzer is to be activated, buzzer output pin of the micro computer alternates between ON and OFF repeatedly at 4kHz and Q302 is turned ON/OFF accordingly. A 4kHz voltage is applied to the buzzer and the diaphragm of the buzzer vibrates to output 4kHz sound.
  • Page 50 6. Service Operation Circuit Micro computer R606 (AX-3T3) Cool FORCE COOL 42 Normal Use the service switch to select “Cooling” temporarily when the interior electric equipment has troubled. Setting the switch to “Cooling” causes continuous cooling room temperature control. To control the room temperature, turn on and off the disconnect switch.
  • Page 51 – 55 –...

  • Page 52: Service Call Q & A

    SERVICE CALL Q & A Cooling operation While cooling, Check whether frost sticks If cooling is performance compressor sometimes stops on the heat exchanger of in- when the room temperature abruptly. door unit or not. is low, frost may stick on the Wait for 3 –...
  • Page 53 Heating operation Air does not come out when It is not a trouble. The fan is When starting the operation, starting a heating operation. stopped to avoid cold wind. the heat exchanger is cold and, therefore, the fan is stopped. Wait 2–3 minutes.
  • Page 54 Automatic operation automatic According to the room operation mode determined? temperature, cooling or dehumidifying operation is automatically selected. Cooling: When room temperature is approx. 27°C or higher Dehumidifying: When room temperature is between approx. 23°C and 27°C Heating: When room temperature is approx.
  • Page 55 Common, etc. There difference There may be a difference between room between room temperature setting and temperature setting and actual room temperature. actual room temperature on account room structure, air flow, etc. If there is a difference from the room temperature, adjust the set temperature to keep living space at a comfortable temperature.
  • Page 56 Wireless remote controller 1) When the “Automatic” 1) When the operation mode room temperature operation mode is “Automatic”, the fan sensing thermistor in the selected, “Automatic” speed is automatically indoor unit detects the room does not change by fixed to “Automatic”. temperature and, according pressing the fan speed to the particular temperature,...
  • Page 57 In spite of timer “Preprogram”, Isn’t the time over the pre- time setting programmed time? extinguished. As soon as the prepro- grammed time is reached, the time setting disappears. After selecting “Dehumidifying” “Dehumidifying” operation operation, the “LO” fan speed” mode, the fan speed mode is forcibly selected.

  • Page 58: Trouble Shooting

    TROUBLE-SHOOTING No cooling or heating *1 Before using the service switch, No operation at all. disengage and engage the plug. Do not Operates by setting the service operate the remote controller. switch to forced cooling? Check the following parts and replace if faulty 1) Current fuse Remove and check the continuity across.
  • Page 59 *4 Wait for 3 minutes before forced Check the circuit board inside parts. re-operation by the service switch. Replace faulty part When checking, carry out a self diagnosis by indoor indicator lamp. CN6 BLUE-RED (V) RAS-18CH7 RAS-24CH7 Fan Speed Cooling Heating Cooling Heating 32.6...
  • Page 60 Timer-Lamp, break-down checking in blinking sign. Check the break-down factor from the frequency of timer-lamp blinking. Mode of Timer-Lamp blinking Indication Factor Estimated Break-Down Part 4-way valve not working (1) 4-way valve is not working. Inside temperature is low in heating (2) Heat-exchanger thermistor is –...

  • Page 61: Parts List And Diagram

    PARTS LIST AND DIAGRAM INDOOR UNIT MODEL : RAS-18CH7/RAS-24CH7 – 65 –...
  • Page 62 MODEL RAS-18CH7 PART N0. Q’TY / UNIT PARTS NAME RAS-18CH7 PMRAS-51CHA1 001 CABINET PMRAS-40CNH2 023 MOUNTING PLATE PMRAS-51CHA1 002 FAN MOTOR PMRAS-18CH5 TANGENTIAL FAN PMRAS-25CNH2 005 P-BEARING ASSY PMRAS-51CHA1 004 FAN MOTOR BASE PMRAS-51CHA1 005 CYCLE ASSY PMRAS-51CHA1 020 FAN COVER...
  • Page 63 MODEL RAS-24CH7 PART N0. Q’TY / UNIT PARTS NAME RAS-24CH7 PMRAS-51CHA1 001 CABINET PMRAS-40CNH2 023 MOUNTING PLATE PMRAS-51CHA1 002 FAN MOTOR PMRAS-18CH5 TANGENTIAL FAN PMRAS-25CNH2 005 P-BEARING ASSY PMRAS-51CHA1 004 FAN MOTOR BASE PMRAS-24JP3 CYCLE ASSY PMRAS-51CHA1 020 FAN COVER PMRAS-18CP5 PIPE SUPPORT PMRAS-24CH3...
  • Page 64 PARTS LIST AND DIAGRAM OUTDOOR UNIT MODEL : RAC-18CH7 – 68 –...
  • Page 65 PARTS LIST AND DIAGRAM OUTDOOR UNIT MODEL : RAC-24CH7 – 69 –...
  • Page 66 MODEL RAC-18CH7 PART N0. Q’TY / UNIT PARTS NAME RAC-18CH7 PMRAC-18CV3 COMPRESSOR PMRA-13CF COMPRESSOR RUBBER PMRAC-51CHA1 908 VALVE (2S) PMRAC-51CHA1 909 VALVE (4S) PMRAC-51CHA1 902 CONDENSER PMRAC-40CNH2 918 FAN MOTOR SUPPORT PMRAC-18CH1 FAN MOTOR PMRAC-40CNH2 917 PROPELLER FAN PMRAC-51CHA1 903 TERMINAL BOARD (4P) PMRAC-63CHA2 907 COMPRESSOR CAPACITOR...
  • Page 67 MODEL RAC24CH7 PART N0. Q’TY / UNIT PARTS NAME RAC-24CH7 PMRAC-63CA2 COMPRESSOR PMRA-13CF COMPRESSOR RUBBER PMRAC-51CHA1 908 VALVE (2S) PMRAS-63CHA2 905 VALVE (5S) PMRAC-24CH3 CONDENSER PMRAC-40CNH2 918 FAN MOTOR SUPPORT PMRAC-18CH1 FAN MOTOR PMRAC-40CNH2 917 PROPELLER FAN PMRAC-51CHA1 903 TERMINAL BOARD (4P) PMRAC-63CHA2 907 COMPRESSOR CAPACITOR CAPACITOR 2.5 µF...
  • Page 68 HITACHI RAS-18CH7 / RAC-18CH7 PM NO. 0346E RAS-24CH7 / RAC-24CH7 Printed in Malaysia...

This manual is also suitable for:

Rac-18ch7Ras-24ch7Rac-24ch7

Table of Contents