Carrier 38MBR series - User Manual

Service Manual
38MBR
Outdoor Unit Single Zone Ductless System
Sizes 36 to 48
TABLE OF CONTENTS
PAGE
SAFETY CONSIDERATIONS 1.........................
INTRODUCTION 1...................................
MODEL/SERIAL NUMBER NOMENCLATURE 2..........
SPECIFICATIONS − OUTDOOR 3.......................
DIMENSIONS − OUTDOOR 4..........................
CLEARANCES − OUTDOOR 6.........................
ELECTRICAL DATA 7................................
WIRING 7...........................................
CONNECTION DIAGRAM 7...........................
WIRING DIAGRAMS 8................................
FAN AND MOTOR SPECIFICATIONS 12.................
REFRIGERATION CYCLE DIAGRAMS 13................
REFRIGERANT LINES 14.............................
SYSTEM EVACUATION AND CHARGING 15.............
SYSTEM VACUUM AND CHARGE 15...................
ELECTRONIC FUNCTIONS 16.........................
TROUBLESHOOTING 18..............................
DIAGNOSIS GUIDES 19...............................
DIAGNOSIS AND SOLUTION 20.......................
DISASSEMBLY INSTRUCTIONS SIZE 36 38..............
DISASSEMBLY INSTRUCTIONS SIZE 48 44..............
SAFETY CONSIDERATIONS
Installing, starting up, and servicing air−conditioning equipment
can be hazardous due to system pressures, electrical components,
and equipment location (roofs, elevated structures, etc.).
Only trained, qualified installers and service mechanics should
install, start−up, and service this equipment.
Untrained personnel can perform basic maintenance functions such
as cleaning coils. All other operations should be performed by
trained service personnel.
When working on the equipment, observe precautions in the
literature and on tags, stickers, and labels attached to the
equipment.
Follow all safety codes. Wear safety glasses and work gloves. Keep
quenching cloth and fire extinguisher nearby when brazing. Use
care in handling, rigging, and setting bulky equipment.
Read this manual thoroughly and follow all warnings or cautions
included in literature and attached to the unit. Consult local building
codes and National Electrical Code (NEC) for special requirements.
Recognize safety information. This is the safety−alert symbol
!
!
.
When you see this symbol on the unit and in instructions or manuals,
be alert to the potential for personal injury. Understand these signal
words: DANGER, WARNING, and CAUTION.
These words are used with the safety−alert symbol. DANGER
identifies the most serious hazards which will result in severe
personal injury or death. WARNING signifies hazards which
could result in personal injury or death. CAUTION is used to
identify unsafe practices which may result in minor personal injury
or product and property damage. NOTE is used to highlight
suggestions which will result in enhanced installation, reliability, or
operation.
!
WARNING
ELECTRICAL SHOCK HAZARD
Failure to follow this warning could result in personal
injury or death.
Before installing, modifying, or servicing system, main
electrical disconnect switch must be in the OFF
position. There may be more than 1 disconnect switch.
Lock out and tag switch with a suitable warning label.
EXPLOSION HAZARD
Failure to follow this warning could
result in death, serious personal injury,
and/or property damage.
Never use air or gases containing
oxygen for leak testing or operating
refrigerant compressors. Pressurized
mixtures of air or gases containing
oxygen can lead to an explosion.
!
WARNING
CAUTION
!
EQUIPMENT DAMAGE HAZARD
Failure to follow this caution may result in equipment
damage or improper operation.
Do not bury more than 36 in. (914 mm) of refrigerant pipe
in the ground. If any section of pipe is buried, there must be
a 6 in. (152 mm) vertical rise to the valve connections on
the outdoor units. If more than the recommended length is
buried, refrigerant may migrate to the cooler buried section
during extended periods of system shutdown. This causes
refrigerant slugging and could possibly damage the
compressor at start−up.
INTRODUCTION
This Service Manual provides the necessary information to service,
repair, and maintain the 38MBR family of heat pumps. Section 2 of
this manual has an appendix with data required to perform
troubleshooting. Use the Table of Contents to locate a desired topic.

Summary

Safety Considerations

Introduction

Model Serial Number Nomenclature

Specifications Outdoor

Dimensions Outdoor

Clearances Outdoor

Electrical Data

Wiring

Recommended Connection Method for Power and Communication Wiring

Details how to connect power and communication wiring to minimize interference.

Wiring Diagrams

Fan and Motor Specifications

Refrigeration Cycle Diagrams

Refrigerant Lines

General Refrigerant Line Sizing

Covers general guidelines for refrigerant line sizing and installation.

Long Line Applications

Details specific considerations for extended refrigerant line applications.

System Evacuation and Charging

Deep Vacuum Method

Explains the deep vacuum method for system evacuation.

Triple Evacuation Method

Details the triple evacuation method for system evacuation.

Final Tubing Check

Provides instructions for final checks of refrigerant tubing.

System Operating Conditions

Electronic Functions

Main Protection

Outlines primary protection mechanisms for the unit.

Compressor Top Temperature Protection

Describes protection against high compressor top temperatures.

Compressor Discharge Temperature Protection

Details protection related to compressor discharge temperature.

Fan Speed is Out of Control

Explains the protection for abnormal fan speeds.

Inverter Module Protection

Covers protection functions of the inverter module.

Indoor Fan Delayed Open Function

Describes the delayed opening function of the indoor fan.

Compressor Preheating Functions

Explains the preheating functions for the compressor.

Operation Modes and Functions

Details various operating modes and functions.

Defrosting Mode

Defrosting Action

Describes the actions taken during defrosting mode.

Condition of Ending Defrosting

Specifies the conditions for ending the defrosting mode.

Point Check Function

Troubleshooting

Required Tools

Lists the necessary tools for diagnosing issues.

Recommended Steps

Provides a step-by-step guide for troubleshooting.

Diagnostic Guides

Diagnosis and Solution

Main Parts Check

Temperature Sensor Checking

Disconnect and measure resistance of temperature sensors.

Compressor Checking

IPM Continuity Check

Disassembly Instructions Size 36

Panel Plate

Procedures for removing the panel plate.

Fan Assy

Steps to remove the fan assembly.

Electrical Parts

Steps for removing electrical components from the unit.

Four-Way Valve

Instructions for removing the four-way valve.

Disassembly Instructions Size 48

Fan Assy

Steps to remove the fan assembly for the size 48 unit.

Panel Plate

Procedures for removing the panel plate for the size 48 unit.

Electrical Parts

Steps for removing electrical components for the size 48 unit.

Compressor

Instructions for removing the compressor.

The 4-Way Valve

Instructions for removing the 4-way valve.

The Expansion Valve

Instructions for removing the expansion valve.

Carrier 38MBR series Specifications

General

Brand	Carrier
Model	38MBR series
Category	Air Conditioner
Language	English