Midea M3OD-27HRDN1-M User Manual

Multi outdoor units
SERVICE MANUAL
Multi zone
CONDENSING UNITS
Revision B: ODMI-C1-1403
Model Numbers:
M2OC-18HFN1-M M3OC-30HRFN1-M
M2OD-18HFN1-M M4OC-36HRFN1-M
M3OD-27HRDN1-M
WARNING
 Installation MUST conform with local building codes or, in the absence of local
codes, with the National Electrical Code NFPA70/ANSI C1-1993 or current edition
and Canadian Electrical Code Part1 CSA C.22.1.
 The information contained in the manual is intended for use by a qualified service
technician familiar with safety procedures and equipped with the proper tools and
test instruments
 Installation or repairs made by unqualified persons can result in hazards to you
and others.
 Failure to carefully read and follow all instructions in this manual can result in
equipment malfunction, property damage, personal injury and/or death.
Table of Contents
1. Product Specifications
2. Indoor Unit Combination
3. Suggested Indoor Unit Model Numbers
4. Dimension Of Outdoor Unit
5. Refrigerant Cycle Diagram
6. Installation Details
7. Electronic Function
8. Wiring Diagrams And Electrical Trouble Shooting
9. Disassembly Instructions
10. Exploded View

Midea M3OD-27HRDN1-M Specifications

General

Cooling Capacity	27000 BTU/h
Power Supply	220-240V, 50Hz
Operating Temperature (Cooling)	18-43 °C
Operating Temperature (Heating)	-7-24 °C
Type	Split System

Summary

Installation Details and Procedures

Wrench Torque for Installation

Specifies torque values for tightening pipe flare nuts during installation.

Cable Connection Guidelines

Provides guidance on connecting power and communication cables for the unit.

Pipe Length and Elevation Limits

Outlines maximum allowable pipe lengths and height differences for installation.

Initial Installation Procedures

Detailed steps for initial installation, including evacuation and leak checks.

Refrigerant Handling Procedures

Instructions for adding refrigerant and re-installing units after repair.

Electronic Function and Control

Abbreviations and Environment Specs

Glossary of terms and specifications for the electric control working environment.

Main Protection Functions

Details on system protections like compressor delay and temperature limits.

System Control Logic

Explains capacity calculation, fan/valve operations, EXV, and defrosting.

Wiring Diagrams

1-Drive Outdoor Unit Wiring Schematics

Electrical wiring diagrams for 1-drive-2, 1-drive-3, and 1-drive-4 outdoor unit configurations.

Troubleshooting and Component Checks

Safety Precautions and Error Displays

Essential safety guidelines, indoor/outdoor unit error codes, and display functions.

Indoor Unit Troubleshooting

Procedures for diagnosing and resolving common indoor unit malfunctions and errors.

Outdoor Unit Troubleshooting

Procedures for diagnosing and resolving common outdoor unit malfunctions and error codes.

Component Testing Criteria

Testing procedures and resistance values for key components like sensors, compressor, and motors.

Disassembly Instructions

Model-Specific Disassembly Procedures

Step-by-step instructions for disassembling various outdoor unit models by component.