Mitsubishi Electric MSZ-HM12NA-U1 User Manual

Outdoor unit service manual
MUZ-HM•NA Series (OBH747)
NOTE:
RoHS compliant products have <G> mark on the spec name plate.
PARTS CATALOG (OBB746)
MSZ-HM24NA
INDOOR UNIT
SERVICE MANUAL
INDOOR UNIT
Models
MSZ-HM09NA
-
U1
MSZ-HM12NA
-
U1
MSZ-HM15NA
-
U1
MSZ-HM18NA
-
U1
MSZ-HM24NA
-
U1
CONTENTS
1. TECHNICAL CHANGES
·······································
2
2. PART NAMES AND FUNCTIONS ····················· 3
3. SPECIFICATION ················································ 5
4. OUTLINES AND DIMENSIONS ························ 7
5. WIRING DIAGRAM ············································ 8
6. REFRIGERANT SYSTEM DIAGRAM ··············· 9
7. SERVICE FUNCTIONS ··································· 10
8. MICROPROCESSOR CONTROL ··················· 12
9. TROUBLESHOOTING ····································· 16
10. DISASSEMBLY INSTRUCTIONS ···················· 30
No. OBH746
REVISED EDITION-B
Please void OBH746 REVISED EDITION-A.
Revision B:
• 3-1. OPERATING RANGE has been modified.

Mitsubishi Electric MSZ-HM12NA-U1 Specifications

General

Brand	Mitsubishi Electric
Model	MSZ-HM12NA-U1
Category	Air Conditioner
Language	English

Summary

Specifications

Operating Range and Conditions

Details the operational voltage, temperature, and humidity ranges.

Wiring Diagram

MSZ-HM09-15NA Wiring Schematics

Illustrates the electrical connections for specific indoor unit models.

MSZ-HM18-24NA Wiring Schematics

Shows the electrical connections for other indoor unit models.

Refrigerant System Diagram

MSZ-HM09-15NA Refrigerant Flow

Depicts the refrigerant circuit and flow for specific indoor unit models.

MSZ-HM18-24NA Refrigerant Flow

Illustrates the refrigerant circuit and flow for other indoor unit models.

Service Functions

Microprocessor Control

Emergency/Test Operation

Details how to use the emergency and test operation modes.

Troubleshooting

Troubleshooting Cautions and Preparation

Provides safety warnings and preliminary checks before troubleshooting.

Failure Mode Recall Function

Explains how to recall and interpret memorized error codes.

Troubleshooting Instructions Flowchart

Guides users through diagnosing operational issues based on symptoms.

Troubleshooting Check Table

Lists specific error codes, symptoms, conditions, and remedies.

Main Parts Trouble Criteria

Provides resistance criteria for checking key components like thermistors.

Indoor Fan Motor Troubleshooting Flow

Step-by-step guide to diagnose indoor fan motor failures.

Remote Controller & Indoor P.C. Board Check

Details checks for remote controller and indoor electronic board issues.

Indoor P.C. Board & Fan Motor Check

Miswiring and Serial Signal Error Check

Test Point Diagrams and Voltages