Mitsubishi Heavy Industries SRF25ZS-W Service Manual
  1. Manuals
  2. Brands
  3. Mitsubishi Heavy Industries Manuals
  4. Air Conditioner
  5. SRF25ZS-W
  6. Service manual

Mitsubishi Heavy Industries SRF25ZS-W Service Manual

Inverter floor standing type residential air-conditioners
Hide thumbs Also See for SRF25ZS-W:
Table of Contents

Advertisement

Quick Links

SERVICE MANUAL
INVERTER FLOOR STANDING TYPE
RESIDENTIAL AIR-CONDITIONERS
(Split system, air to air heat pump type)
SRF25ZS-W / SRC25ZS-W2
SRF35ZS-W / SRC35ZS-W2
SRF50ZSX-W / SRC50ZSX-W2
Manual No.'20 • SRF-SM-311

Advertisement

Table of Contents
loading
Need help?

Need help?

Do you have a question about the SRF25ZS-W and is the answer not in the manual?

Questions and answers

Related Manuals for Mitsubishi Heavy Industries SRF25ZS-W

Summary of Contents for Mitsubishi Heavy Industries SRF25ZS-W

  • Page 1 Manual No.’20 • SRF-SM-311 SERVICE MANUAL INVERTER FLOOR STANDING TYPE RESIDENTIAL AIR-CONDITIONERS (Split system, air to air heat pump type) SRF25ZS-W / SRC25ZS-W2 SRF35ZS-W / SRC35ZS-W2 SRF50ZSX-W / SRC50ZSX-W2...

  • Page 2: Table Of Contents

    '20 • SRF-SM-311 CONTENTS 1. OUTLINE OF OPERATION CONTROL BY MICROCOMPUTER ....(1) Operation control function by wireless remote control ......................(2) Unit ON/OFF button (3) Auto restart function ................(4) Installing two air-conditioners in the same room ........(5) Selection of the annual cooling function ..........

  • Page 3: Outline Of Operation Control By Microcomputer

    '20 • SRF-SM-311 1. OUTLINE OF OPERATION CONTROL BY MICROCOMPUTER (1) Operation control function by wireless remote control Operation section Transmission section OPERATION MODE select button ON/OFF (luminous) button Each time the button is pressed, the mode changes. Press to start operation, press again to stop.

  • Page 4: Unit On/Off Button

    '20 • SRF-SM-311 (2) Unit ON/OFF button When the wireless remote control batteries become weak, or if the wireless remote control is lost or malfunctioning, this button may be used to turn the unit on and off. (a) Operation Push the button once to place the unit in the automatic mode. Push it once more to turn the unit off. (b) Details of operation The unit will go into the automatic mode in which it automatically determines, from indoor temperature (as detected by sensor), whether to go into COOL, DRY or HEAT modes.

  • Page 5: Selection Of The Annual Cooling Function

    '20 • SRF-SM-311 (5) Selection of the annual cooling function (a) The annual cooling control is valid from factory default setting. It is possible to disable by cutting jumper wire (J172), or changing the setting of DIP switch (SW2-4) on the interface kit (option) PCB if it is connected. Interface kit Jumper wire (SC-BIKN2-E)

  • Page 6: Flap Control

    '20 • SRF-SM-311 (8) Flap control   Control the flap by AIR FLOW (UP/DOWN) button on the wireless remote control. (a) Flap   Each time when you press the AIR FLOW (UP/DOWN) button the mode changes as follows. (Flap stopped) (Swing)  ...

  • Page 7: Timer Operation

    Timer operation (ON timer, OFF timer) can be set up to 4 times a day for each weekday. (11) Silent mode As “Silent mode start” signal is received from the wireless remote control, it operates by dropping the outdoor fan tap and the compressor command speed. SRF25ZS-W SRF35ZS-W SRF50ZSX-W Cooling Heating Cooling Heating Cooling Heating...
  • Page 8 (i) Fuzzy operation Deviation between the room temperature setting correction temperature and the return air temperature is calculated in accordance with the fuzzy rule, and used for control of the air capacity and the compressor speed. Model SRF25ZS-W SRF35ZS-W SRF50ZSX-W Fan speed...

  • Page 9: Outline Of Cooling Operation

    (b) Detail of control in each mode (Pattern) (i) Fuzzy operation During the fuzzy operation, the air flow and the compressor speed are controlled by calculating the difference between the room temperature setting correction temperature and the return air temperature. Model SRF25ZS-W SRF35ZS-W SRF50ZSX-W Fan speed Auto...

  • Page 10: Outline Of Dehumidifying (Dry) Operation

    '20 • SRF-SM-311 (15) Outline of dehumidifying (DRY) operationion (a) Purpose of DRY mode The purpose is "Dehumidification", and not to control the humidity to the target condition. Indoor/outdoor unit control the operation condition to reduce the humidity, and also prevent over cooling. (b) Outline of control (i) Indoor fan speed and compressor are controlled by the area which is selected by the temperature difference.

  • Page 11: Protective Control Function

    SP ＋ 1 SP − 1 Indoor air temperature−Setting temperature (˚C) ※It can not be changed to heating mode if outdoor air temperature is 28℃ or higher. '20 • SRF-SM-311 (c) When the unit is started again within one hour after the stop of automatic operation or when the automatic operation is selected during heating, cooling or dehumidifying operation, the unit is operated in the previous operation mode.
  • Page 12 '20 • SRF-SM-311 (17) Frost prevention control (b) Frost prevention control (During cooling or dehumidifying) ( i ) Operating conditions (ii) Detail of anti-frost operation Reset Operation mode Protective control Reset Protective Item control Compressor operation Forced outage Operation instruction Indoor fan Depends on operation mode Indoor heat exchanger...
  • Page 13 '20 • SRF-SM-311 Compressor speed (Example) 6 (8) rps After lapse of 30 (20) sec. or over After lapse of 30 (20) sec. or over 6 (8) rps lower limit After lapse of 30 (20) sec. or over speed 30 rps 0rps Outdoor heat exchanger temperature (°C) Notes (1) When the outdoor heat exchanger temperature is in the range of P2-P3 ºC, the speed is reduced by 6 (8) rps at each 30 (20) seconds.
  • Page 14 '20 • SRF-SM-311 ( f ) Heating high pressure control (i) Starting condition When the indoor heart exchanger temperature (Th2) has risen to a specified temperature while the compressor is turned on. (ii) Compressor speed is controlled according to the zones of indoor heat exchanger temperature as shown by the following table.
  • Page 15 '20 • SRF-SM-311 Upper 75 rps Lower 40 rps Upper 90 rps Lower 30 rps Outdoor air temperature(ºC) 3) Reset condition The outdoor air temperature (TH2) is lower than 11ºC (h) Heating low outdoor temperature protective control • Models SRF25, 35 (i) Operating conditions When the outdoor air temperature (TH2) is -2°C or lower continues for 30 seconds while the compressor command speed is other than 0 rps...
  • Page 16 '20 • SRF-SM-311 ( i ) Compressor overheat protection (i) Purpose It is designed to prevent deterioration of oil, burnout of motor coil and other trouble resulting from the compressor overheat. (ii) Detail of operation 1) Speeds are controlled with temperature detected by the sensor mounted on the discharge pipe. (Example) Fuzzy 4 rps After lapse of 1(3) min.
  • Page 17 '20 • SRF-SM-311 (k) Current cut (i) Purpose Inverter is protected from overcurrent. (ii) Detail of operation Output current from the inverter is monitored with a shunt resistor and, if the current exceeds the setting value, the com- pressor is stopped immediately. Operation starts again after a delay time of 3 minutes. ( l ) Outdoor unit failure This is a function for determining when there is trouble with the outdoor unit during air-conditioning.
  • Page 18 '20 • SRF-SM-311 3) Reset conditions When either of the following conditions is satisfied a) The outdoor air temperature (TH2) is 25ºC or higher. b) The compressor command speed is 0 rps. (ii) Heating 1) Operating conditions When the outdoor air temperature (TH2) is 0ºC (SRF50 : 4ºC) or lower continues for 30 seconds while the compressor command speed is other than 0 rps 2) Detail of operation The outdoor fan is stepped up by 2 speed step at each 20 seconds.

  • Page 19: Maintenance Data

    '09•SRK-DB-087D '20 • SRF-SM-311 Reference Reference 2. MAINTENANCE DATA 2 TROUBLESHOOTING PROCEDURES FOR ELECTRICAL EQUIPMENT (1) Cautions (2) Items to check before troubleshooting source (3) Troubleshooting procedure (If the air-conditioner does not run at all) Important satisfied source wireless proced-...

  • Page 20: Troubleshooting Procedure (If The Air-Conditioner Runs)

    '09•SRK-DB-087D '20 • SRF-SM-311 (4) Troubleshooting procedure (If the air-conditioner runs) 21-27. 21-27.

  • Page 21: Self-Diagnosis Table

    '20 • SRF-SM-311 (5) Self-diagnosis table Wired Indoor unit display panel remote Description Cause Display (flashing) condition control TIMER of trouble display light light • Broken heat exchanger When a heat exchanger temperature sensor 1 wire disconnection is Heat exchanger 1-time temperature sensor 1 wire, detected while operation is stopped.

  • Page 22: Service Mode (Trouble Mode Access Function)

    '09•SRK-DB-087D '20 • SRF-SM-311 (6) Service mode (Trouble mode access function) (a) Explanation of terms Explanation Term The service mode is the mode where service data are displayed by flashing of the display lights Service mode when the operations in item (b) below are performed with the indoor control. These are the contents of error displays and protective stops which occurred in the past in the air- conditioner system.
  • Page 23 '09•SRK-DB-087D '20 • SRF-SM-311 4-time flash 2-time flash. wireless mode mode Self-diagnosis data What are self-diagnosis Data? wireless mode mode Wireless remote control setting Contents of output data Operation mode Fan speed mode wireless Indicates the number of Wireless remote control setting occasions previous to the present Temperature setting the error display data are from.
  • Page 24 '09•SRK-DB-087D '20 • SRF-SM-311 (Example) Wireless remote control setting Operation Displayed data Fan speed Temperature mode mode setting Displays the reason for the stop (error code) the previous time an error was displayed. 21ºC Displays the reason for the stop (error code) 2 times previous when an error was displayed. 22ºC Cooling 23ºC...
  • Page 25 '20 • SRF-SM-311 (c) Error code, stop code table Number of flashes when in service mode Stop code Error Auto TIMER Error content Cause Occurrence conditions display recovery light light Error code (10's digit) (1's digit) Normal The wired remote control wire Y is open. The wired remote 1-time Error of wired remote control Broken wired remote control wire,...
  • Page 26 '09•SRK-DB-087D '20 • SRF-SM-311 4-time flash 2-time flash. (d) Operation mode, Fan speed mode information tables (ii) mode mode Display pattern when Display pattern when Fan speed in service mode in service mode Operation mode mode when when there is an there is an RUN light TIMER light...
  • Page 27 '09•SRK-DB-087D '20 • SRF-SM-311 (e) Temperatare information (i) Room temperature sensor, indoor heat exchanger temperature sensor, outdoor air temperature sensor, outdoor heat exchanger temperature sensor Unit: °C TIMER light (1’s digit) RUN light (10’s digit) Buzzer sound (sounds for 0.1 second) (does not sound) temperature information Sensor name...
  • Page 28 '09•SRK-DB-087D '20 • SRF-SM-311 Discharge pipe temperature sensor (ii) Unit: °C TIMER light (1’s digit) RUN light (10’s digit) Buzzer sound (sounds for 0.1 second) (does not sound) temperature information Sensor value displayed when the error code is normal temperature sensor -64ºC data 0.1 sec.
  • Page 29 '09•SRK-DB-087D '20 • SRF-SM-311 Service data record form Wireless r Operation mode Fan speed mode temperature Wireless r temperature temperature temperature temperature Wireless r temperature temperature temperature temperature Wireless r temperature temperature temperature temperature Wireless r temperature temperature temperature temperature Wireless r temperature temperature...

  • Page 30: Inspection Procedures Corresponding To Detail Of Trouble

    '09•SRK-DB-087D '20 • SRF-SM-311 (7) Inspection procedures corresponding to detail of trouble Sensor error Broken sensor wire, connector poor connection Temperature sensor characteristics (Room Discharge pipe temperature sensor characteristics temperature, indoor heat exchanger temperature, outdoor heat exchanger temperature, outdoor air temperature) (Short-circuit) (Short-circuit) - 10...
  • Page 31 '09•SRK-DB-087D '20 • SRF-SM-311 Current cut Compressor lock, Compressor wiring short-circuit, Compressor output is open phase, Outdoor unit PCB is faulty, Service valve is closed, EEV is faulty, Compressor faulty. short-circuit? unit ＊   Defective outdoor unit PCB ＊ Defective outdoor unit PCB between terminals.
  • Page 32 '09•SRK-DB-087D '20 • SRF-SM-311 Over heat of compressor Gas shortage, defective discharge pipe temperature sensor temperature temperature Defective outdoor unit PCB Error of signal transmission Wiring error including power cable, defective indoor/ outdoor unit PCB ② ③ unit ② ③ unit ①...
  • Page 33 '09•SRK-DB-087D '20 • SRF-SM-311 Trouble of outdoor unit Insufficient refregerant amount, Faulty power transistor, Broken compressor wire Service valve close, Defective EEV, Defective outdoor unit PCB unit ◆  unit     defrost operation   minutes or more Notes (1) (2) Check resistance between terminals, see page 30. unit between terminals ．...

  • Page 34: Phenomenon Observed After Shortcircuit, Wire Breakage On Sensor

    '20 • SRF-SM-311 Rotor lock Defective compressor, defective outdoor unit PCB unit between terminals. See page 30. (8) Phenomenon observed after shortcircuit, wire breakage on sensor (a) Indoor unit Phenomenon Operation Sensor mode Shortcircuit Disconnected wire Cooling Room temperature (8) Phenomenon observed after short-circuit, wire breakage on sensor sensor Heating (a) Indoor unit...

  • Page 35: Checking The Indoor Electrical Equipment

    Phenomenon Operation Sensor mode Cooling Heat exchanger Shortcircuit Disconnected wire sensor Heating Cooling Defrosting is performed for 10 minutes at approx. 35 minutes. Heat exchanger sensor Cooling Ourdoor air Heating Defrosting is performed for 10 minutes at approx. 35 minutes. '20 •...

  • Page 36: How To Make Sure Of Wireless Remote Control

    Operation SW ON Measure in this section '20 • SRF-SM-311 (10) How to make sure of wireless remote control wireless wireless wireless wireless wireless wireless Simplified check method of wireless remote control   It is normal if the signal transmission section of the wireless remote control emits a whitish light at each transmission on the monitor of digital camera.

  • Page 37: Outdoor Unit Inspection Points

    '20 • SRF-SM-311 (12) Outdoor unit inspection points Models SRC25ZS-W2, 35ZS-W2 ◆Check point of outdoor unit WARNING- HIGH VOLTAGE ◆Power source and serial signal inspection High voltage is produced in the control box. Don't touch electrical parts in the control box for 5 minutes after the : AC 220/230/240V unit is stopped.
  • Page 38 '20 • SRF-SM-311 Model SRC50ZSX-W2 ◆Check point of outdoor unit CAUTION - HIGH VOLTAGE High voltage is produced in the control box. Don't touch ◆Power source and serial signal inspection electrical parts in the control box for 5 minutes after the : AC220/230/240V unit is stopped.
  • Page 39 '09•SRK-DB-087D '20 • SRF-SM-311 (a) Inspection of electronic expansion valve Electronic expansion valve operates for approx. 10 seconds after the power on, in order to determine its aperture. Check the operating sound and voltage during the period of time. (Voltage cannot be checked during operation in which only the aperture change occurs.) (ii) (iii)

  • Page 40: Electrical Wiring

    '20 • SRF-SM-311 3. ELECTRICAL WIRING (1) Indoor units Models SRF25ZS-W, 35ZS-W, 50ZSX-W RWB000Z057...
  • Page 41 '20 • SRF-SM-311 (2) Outdoor units Models SRC25ZS-W2, 35ZS-W2 RWC000Z315...
  • Page 42 '20 • SRF-SM-311 Model SRC50ZSX-W2 RWC000Z306...

  • Page 43: Piping System

    '20 • SRF-SM-311 4. PIPING SYSTEM Models SRK20ZJX-S, 25ZJX-S, 35ZJX-S Models SRF25ZS-W, 35ZS-W Cooling cycle Heating cycle Indoor unit Outdoor unit Outdoor air Flare temperature sensor connection Service valve (TH2) (Gas) Discharge pipe temperature sensor Heat Gas pipe Room Check joint...
  • Page 44 MITSUBISHI HEAVY INDUSTRIES THERMAL SYSTEMS, LTD. 2-3, Marunouchi 3-chome, Chiyoda-ku, Tokyo, 100-8332, Japan http://www.mhi-mth.co.jp/en/ Because of our policy of continuous improvement, we reserve the right to make changes in all specifications without notice. Copyright MITSUBISHI HEAVY INDUSTRIES THERMAL SYSTEMS, LTD.

This manual is also suitable for:

Src25zs-w2Srf35zs-wSrc35zs-w2Srf50zsx-wSrc50zsx-w2

Table of Contents