Mitsubishi MSH-A24WV User Manual

SERVICE MANUAL
CONTENTS
1. TECHNICAL CHANGES ····································2
2. PART NAMES AND FUNCTIONS······················2
3. SPECIFICATION·················································4
4. NOISE CRITERIA CURVES·······························5
5. OUTLINES AND DIMENSIONS ·························6
6. WIRING DIAGRAM ············································7
7. REFRIGERANT SYSTEM DIAGRAM················8
8. MICROPROCESSOR CONTROL ······················9
9. SERVICE FUNCTIONS ····································18
10. TROUBLESHOOTING······································20
11. DISASSEMBLY INSTRUCTIONS·····················28
12. PARTS LIST······················································30
13. OPTIONAL PARTS ······················BACK COVER
Wireless type
Models
MSH-A18WV -
(
WH
)
MSH-A24WV -
(
WH
)
MSH-A30WV -
(
WH
)
E1
E1
E1
No. OB321
SPLIT-TYPE, HEAT PUMP AIR CONDITIONERS
MSH-A18WV -
MSH-A24WV -
MSH-A30WV -
E1
E1
E1
NOTE:
This service manual describes technical data of the indoor unit.
•Refer to the service manual OB322 when MSH-A18WV- , MSH-A24WV- or MSH-A30WV- is
connected with MUH-A18WV- , MUH-A24WV- or MUH-A30WV- .
•Refer to the service manual OB319 when MSH-A18WV- is connected with MXZ-A18WV- ,
MXZ-A26WV- or MXZ-A32WV- as multi system units.
•Refer to the service manual OB319 when MSH-A24WV- is connected with MXZ-A26WV- or
MXZ-A32WV- as multi system units.
E1
E1E1
E1E1
E1E1
E1E1E1
E1E1E1
Indication of model name
OB321-1.qxp 03.11.13 4:03 PM Page 1

Mitsubishi MSH-A24WV Specifications

General

Brand	Mitsubishi
Model	MSH-A24WV
Category	Air Conditioner
Language	English

Summary

3 SPECIFICATION

MSH-A18/A24WV Unit Specifications

MSH-A30WV Unit Specifications

6 WIRING DIAGRAM

Indoor Unit Electrical Wiring

7 REFRIGERANT SYSTEM DIAGRAM

Indoor Unit Refrigerant Circuit

8 MICROPROCESSOR CONTROL

Remote Controller and Indicator Functions

"I FEEL CONTROL" Mode Operation

Explains the "I FEEL CONTROL" mode, its operation logic, and temperature determination.

FEEL CONTROL Mode Logic

Set Temperature Determination

FEEL CONTROL Mode Operation Details

COOL Mode "I FEEL CONTROL"

Covers fan speed control, coil frost prevention, and operation in COOL mode "I FEEL CONTROL".

DRY Mode "I FEEL CONTROL" Operation

Details fan speed control and compressor/fan operation in DRY mode "I FEEL CONTROL".

FEEL CONTROL HEAT Mode Logic

HEAT Mode "I FEEL CONTROL" Operation

Explains fan speed control, cold air prevention, and warm air control in HEAT mode "I FEEL CONTROL".

STANDARD OPERATION MODES

Mode Selection and Fan Control

VANE OPERATION MODES

Horizontal Vane Control

ENERGY SAVING AND LONG MODES

EconCool Energy Saving

VERTICAL VANE AND TIMER OPERATIONS

Vertical Vane Control Modes

8-7. TIMER OPERATION

Setting ON/OFF Timers

Provides step-by-step instructions on how to set ON and OFF timers for the air conditioner.

TIMER AND EMERGENCY OPERATIONS

Emergency Test Operation

Describes how to use the emergency operation switch for testing and servicing purposes.

9 SERVICE FUNCTIONS

Timer Short Mode & PC Board Modification

Explains service adjustments for timer settings and PC board modification for individual unit control.

Auto Restart Function

AUTO RESTART FUNCTION MANAGEMENT

Disabling Auto Restart

10 TROUBLESHOOTING GUIDE

Pre-Troubleshooting Checks

Lists important safety and preparatory steps before troubleshooting the unit.

Troubleshooting Steps & Battery Replacement

TROUBLESHOOTING FLOWCHART

Diagnostic Decision Tree

A decision tree to diagnose issues based on indicator lamp flashes and unit behavior.

TROUBLESHOOTING CHECK TABLE

Fault Indicators and Symptoms

A table correlating indicator lamp patterns, symptoms, detection methods, and checkpoints for faults.

MAIN PART TROUBLE CRITERIA

Component Resistance and Voltage Checks

Provides resistance values for thermistors/motors and checks for component faults.

COMPONENT DIAGNOSIS PROCEDURES

Indoor Fan Motor & Remote System Diagnosis

ELECTRONIC CONTROL BOARD DIAGNOSTICS

Indoor P.C. Board Fault Checking

WIRING AND CONNECTION CHECKS

Mis-wiring Check Procedure

Detailed steps to identify and rectify potential mis-wiring issues in the unit's connections.

TEST POINT DIAGRAMS

Indoor Electronic & Receiver P.C. Board Test Points

11 DISASSEMBLY INSTRUCTIONS

Front Panel & Electronic Board Removal