Carrier 38MARB User Manual

Specifications subject to change without notice.
TABLE of CONTENTS
PAGE
INTRODUCTION............................................................................ 1
MODEL / SERIAL NUMBER NOMENCLATURES .................... 2
WIRING........................................................................................... 3
CONNECTION DIAGRAMS ......................................................... 4
WIRING DIAGRAMS..................................................................... 5
REFRIGERATION CYCLE DIAGRAMS...................................... 9
REFRIGERANT LINES .................................................................. 16
SYSTEM EVACUATION AND CHARGING ............................... 17
ELECTRONIC FUNCTIONS ......................................................... 18
INQUIRY MODE ............................................................................ 23
TROUBLESHOOTING................................................................... 24
INDOOR UNIT DIAGNOSTIC GUIDES....................................... 25
DIAGNOSIS AND SOLUTION...................................................... 26
DISASSEMBLY INSTRUCTIONS ................................................ 58
APPENDICIES ................................................................................ 81
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
coil cleaning. 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 a
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 the 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.
INTRODUCTION
This service manual provides the necessary information to service,
repair, and maintain the 38MARB family of heat pumps. This manual
has an “APPENDICIES” with data required to perform
troubleshooting. Use the “TABLE of CONTENTS” to locate a desired
topic.
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.
WAR N I N G
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.
WAR N I N G
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.
CAUTION
Service Manual
38MARB
Outdoor Unit Single Zone Ductless System
Sizes 06 to 36

Carrier 38MARB Specifications

General

Cooling Capacity	9, 000 - 36, 000 BTU/h
Refrigerant	R-410A
Voltage	208/230V
Phase	1
Type	Heat Pump
Compressor Type	Inverter
Sound Level	19 - 49 dB (Indoor Unit)

Summary

Introduction

Model / Serial Number Nomenclature

Wiring

Connection Diagrams

Wiring Diagrams

Refrigeration Cycle Diagrams

Refrigerant Lines

General Refrigerant Line Sizing

Guidelines for sizing refrigerant lines, insulation, and pipe burial requirements.

System Evacuation and Charging

Deep Vacuum Method

Procedure for system evacuation using a vacuum pump to 500 microns.

Electronic Functions

Operation Modes and Functions

Details operating modes, fan control, and running rules for cooling.

Defrost Mode

Troubleshooting

Indoor Unit Diagnostic Guides

Diagnosis and Solution

Outdoor Unit Error Display

Error codes for outdoor units and troubleshooting steps.

Indoor Fan Speed Out of Range (EH03)

Troubleshooting for EH03: Indoor fan speed outside normal range.

Outdoor Fan Speed Out of Range (EC07)

Troubleshooting for EC07: Outdoor fan speed outside normal range.

Indoor Temperature Sensor Errors (EH60)

Troubleshooting for EH60: Indoor temp sensor open/short circuit.

Outdoor Temperature Sensor Errors (EC53)

Troubleshooting for EC53: Outdoor temp sensor open/short circuit.

Refrigerant Leakage Detection (EL0C)

Detects refrigerant leakage based on T2 and compressor frequency.

Current Overload Protection (PC08)

Troubleshooting for PC08: Current overload protection.

Compressor Check

Procedure to check compressor resistance values.

Over Voltage/Low Voltage Protection (PC01)

Troubleshooting for PC01: Over voltage/low voltage protection.

Inverter Compressor Drive Error (PC04)

Troubleshooting for PC04: Inverter compressor drive error.

Low Pressure Protection (PC03)

Troubleshooting for PC03: Low pressure protection.

Check Procedures

Temperature Sensor Check

Procedure to check temperature sensors by measuring resistance.

Compressor Check

IPM Continuity Check

4 - Way Valve Check

EXV Check

Main Parts Check

Disassembly Instructions

Outdoor Unit Panel Plate Disassembly

Instructions for disassembling the panel plate of 12K outdoor units.

Electrical Parts

PCB Board Replacement

Procedure for removing and replacing the PCB board for 12K models.

Fan Assembly

Fan Motor Replacement

Procedure for removing and replacing the fan motor.

Four Way Valve

Compressor

Safety Caution

Appendices

Appendix 1: Temperature Sensor Resistance Values

Table of temperature sensor resistance values for T1, T2, T3, T4.