Mitsubishi MSH-18RV User Manual

SERVICE MANUAL
CONTENTS
1. TECHNICAL CHANGES ····································2
2. PART NAMES AND FUNCTIONS······················2
3. SPECIFICATION·················································6
4. NOISE CRITERIA CURVES·······························8
5. OUTLINES AND DIMENSIONS ······················ 10
6. WIRING DIAGRAM ··········································13
7. REFRIGERANT SYSTEM DIAGRAM··············17
8. PERFORMANCE CURVES······························20
9. MICROPROCESSOR CONTROL ····················36
10. SERVICE FUNCTIONS·····································50
11. TROUBLESHOOTING······································52
12. DISASSEMBLY INSTRUCTIONS·····················71
13. PARTS LIST······················································79
14. OPTIONAL PARTS···········································88
Wireless type
Models
MSH-18RV -
(
WH
)
· MUH-18RV -
· MUH-18RV -
MSH-24RV -
(
WH
)
· MUH-24RV -
MSH-30RV -
(
WH
)
· MUH-30RV -
E1E1
E1E1
E2
E1E1
No. OB272
REVISED EDITION-A
SPLIT-TYPE, HEAT PUMP AIR CONDITIONERS
MSH-18RV -
MSH-24RV -
E1
E1
Revision:
● MUH-18RV- has been added.
MUH-18RV- ➔ MUH-18RV-
•Path of outdoor heat exchanger has changed.
E2E1
E2
•Refer to the Service Manual OB185 REVISED EDITION C when MSH-18RV- is connected
with MXZ-32NV- or MXZ-32NV- as multi system units.
•Refer to the Service Manual OB227 REVISED EDITION-B when MSH-18RV- is connected
with MXZ-32RV- as multi system units.
•Refer to the Service Manual OB254 when MSH-18RV- is connected with MXZ-32SV- as
multi system units.
E1E1
E1
E1
E2E1
E1
OB272-1.qxp 02.1.26 1:22 PM Page 1

Mitsubishi MSH-18RV Specifications

General

Brand	Mitsubishi
Model	MSH-18RV
Category	Air Conditioner
Language	English

Summary

Technical Changes in Air Conditioner Models

Part Identification and Functionality

Remote Controller Overview

Air Conditioner Specifications

Wiring Diagrams

MSH-18RV-E1 Indoor Unit Wiring Diagram

Electrical wiring schematic for the MSH-18RV-E1 indoor unit.

MUH-18RV-E1 Outdoor Unit Wiring Diagram

Electrical wiring schematic for the MUH-18RV-E1 outdoor unit.

MUH-18RV-E2 Outdoor Unit Wiring Diagram

Electrical wiring schematic for the MUH-18RV-E2 outdoor unit.

MSH-24RV-E1 Indoor Unit Wiring Diagram

Electrical wiring schematic for the MSH-24RV-E1 indoor unit.

MUH-24RV-E1 Outdoor Unit Wiring Diagram

Electrical wiring schematic for the MUH-24RV-E1 outdoor unit.

MSH-30RV-E1 Indoor Unit Wiring Diagram

Electrical wiring schematic for the MSH-30RV-E1 indoor unit.

MUH-30RV-E1 Outdoor Unit Wiring Diagram

Electrical wiring schematic for the MUH-30RV-E1 outdoor unit.

Refrigerant System Diagrams

MSH-18RV-E1 / MUH-18RV Units Refrigerant Diagram

Refrigerant flow diagram for MSH-18RV-E1 and MUH-18RV units.

MSH-24RV-E1 / MUH-24RV-E1 Refrigerant Diagram

Refrigerant flow diagram for MSH-24RV-E1 and MUH-24RV-E1 units.

MSH-30RV-E1 / MUH-30RV-E1 Refrigerant Diagram

Refrigerant flow diagram for MSH-30RV-E1 and MUH-30RV-E1 units.

Maximum Refrigerant Piping Length

Performance Curves

Cooling Performance Curves

Heating Performance Curves

Outdoor Pressure and Current Curves (Cool Operation)

Microprocessor Control Features

Wireless Remote Controller Operation

"I FEEL CONTROL" Operation Modes

Describes operation modes based on room temperature.

COOL, DRY, and HEAT Mode Operations

Indoor Fan Motor Control

Auto Vane Operation

Timer Operation Settings

Instructions for setting and canceling timer functions.

Emergency-Test Operation Procedures

Procedures for test runs and emergency operation.

LEV Control Operation Logic

Control logic for the electronic expansion valve (LEV).

Service Functions and Modifications

Compulsory Defrosting Mode for Service

Activating defrost mode manually for servicing.

Changing Defrost Settings

Auto Restart Function Setup

Troubleshooting Guide

Cautions on Troubleshooting Procedures

Safety precautions and preliminary checks before troubleshooting.

Troubleshooting Check Table

Table correlating symptoms, indications, and troubleshooting steps.

Troubleshooting Flowcharts (MSH-18RV)

Step-by-step diagnostic flowcharts for MSH-18RV unit malfunctions.

Troubleshooting Flowcharts (MSH-24/30RV)

Step-by-step diagnostic flowcharts for MSH-24/30RV unit malfunctions.

Checking LEV (Expansion Valve) Faults

Troubleshooting steps for the electronic expansion valve.

Checking Outdoor Thermistor Faults

Diagnosing faults with outdoor thermistors.

Test Point Diagrams and Voltage Checks

Disassembly Instructions