Carrier 38MARBQ12AA3 User Manual

Specifications subject to change without notice.
TABLE of CONTENTS
PAGE
INTRODUCTION............................................................................ 1
MODEL / SERIAL NUMBER NOMENCLATURES .................... 2
SPECIFICATIONS - HEAT PUMP ................................................ 3
DIMENSIONS AND WEIGHTS .................................................... 4
CLEARANCES................................................................................ 7
ELECTRICAL DATA ..................................................................... 8
WIRING........................................................................................... 8
CONNECTION DIAGRAMS ......................................................... 9
WIRING DIAGRAMS..................................................................... 10
FAN AND MOTOR SPECIFICATIONS........................................ 14
REFRIGERATION CYCLE DIAGRAMS...................................... 15
REFRIGERANT LINES .................................................................. 22
SYSTEM EVACUATION AND CHARGING ............................... 23
ELECTRONIC FUNCTIONS ......................................................... 24
POINT CHECK FUNCTION .......................................................... 29
TROUBLESHOOTING................................................................... 30
INDOOR UNIT DIAGNOSTIC GUIDES....................................... 31
DIAGNOSIS AND SOLUTION...................................................... 32
DISASSEMBLY INSTRUCTIONS ................................................ 65
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. Section 2 of
this manual has an appendix 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 09 to 36

Carrier 38MARBQ12AA3 Specifications

General

Cooling Capacity (BTU)	12, 000
Refrigerant	R-410A
Voltage	208/230
Phase	1
Compressor Type	Inverter
Type	Mini Split Heat Pump
Heating Capacity (BTU)	12000
HSPF Rating	10

Summary

INTRODUCTION

MODEL / SERIAL NUMBER NOMENCLATURES

SPECIFICATIONS - HEAT PUMP

DIMENSIONS AND WEIGHTS

CLEARANCES

ELECTRICAL DATA

WIRING

Provides guidelines for power and communication wiring connections.

CONNECTION DIAGRAMS

WIRING DIAGRAMS

FAN AND MOTOR SPECIFICATIONS

REFRIGERATION CYCLE DIAGRAMS

REFRIGERANT LINES

SYSTEM EVACUATION AND CHARGING

Deep Vacuum Method

Explains the deep vacuum method for system evacuation using a vacuum pump.

Triple Evacuation Method

Outlines the triple evacuation method for system evacuation.

Final Tubing Check

Instructions for checking tubing integrity before final assembly.

ELECTRONIC FUNCTIONS

Main Protection

Details main protection functions like compressor restart delay and high temp cutout.

Operation Modes and Functions

Explains operation modes (FAN, COOLING) and compressor/fan running rules.

FAN Mode

Describes the unit's operation in FAN mode.

COOLING Mode

Covers compressor and outdoor fan running rules in COOLING mode.

Indoor Fan Running Rules

Defines indoor fan operation rules for COOLING and HEATING modes.

Compressor Temperature Protection

Explains compressor temperature protection mechanisms.

Evaporator Temperature Protection

Describes evaporator temperature protection that stops the compressor.

HEATING Mode

Details compressor and outdoor fan running rules for HEATING mode.

Evaporator Coil Temperature Protection

Describes evaporator coil temperature protection that stops the compressor.

AUTO Mode

Explains AUTO mode selection and unit behavior.

DRYING mode

Details the DRYING mode operation and low room temperature protection.

FORCED OPERATION Function

How to enter and use forced operation modes (AUTO, COOLING).

Operation Rules

Explains operation rules for FORCED COOLING and FORCED AUTO modes.

AUTO-RESTART function

Describes the auto-restart function after a power failure.

Refrigerant Leakage Detection

Details refrigerant leakage detection and its display indication.

46°F (8°C) Heating

Describes fan and compressor operation during 46°F (8°C) heating.

DEFROST Mode

Forced DEFROSTING Mode

Describes how to enter and exit the forced DEFROSTING mode.

Defrost Exit Conditions

Lists conditions that will cancel the DEFROST mode and revert to HEATING.

POINT CHECK FUNCTION

TROUBLESHOOTING

Safety

Important safety notes regarding electrical discharge before troubleshooting.

INDOOR UNIT DIAGNOSTIC GUIDES

DIAGNOSIS AND SOLUTION

Outdoor Unit Error Display

Details outdoor unit error displays and their corresponding solutions.

Outdoor EEPROM Parameter Error or Compressor Driven Chip EEPROM Parameter Error (EC51)

Troubleshooting for EEPROM parameter or compressor driven chip errors.

Indoor and Outdoor Unit Communication Error (EL01)

Troubleshooting for indoor/outdoor unit communication errors (EL01).

Zero Crossing Detection Error Diagnosis and Solution (EH02)

Troubleshooting for zero crossing detection errors (EH02).

The indoor fan speed is operating outside of the normal range (EH03)

Troubleshooting for indoor fan speed operating outside normal range (EH03).

DC Fan Motor (Control chip is in the fan motor)

Checks for DC fan motor voltage input and output.

The Outdoor Fan Speed is Operating Outside of Normal Range (EC07)

Troubleshooting for outdoor fan speed operating outside normal range (EC07).

Outdoor DC Fan Motor (DC motor that controls the chip on the PCB)

Procedures for checking outdoor DC fan motor resistance and voltage.

Indoor Temperature Sensor Is an Open Circuit or a Short Circuit (T1, T2) (EH60)

Troubleshooting for indoor temperature sensor faults (EH60).

Outdoor Temperature Sensor Is an Open Circuit or Short Circuited (T3, T4, TP, T2B, TH) (EC53)

Troubleshooting for outdoor temperature sensor faults (EC53).

Refrigerant Leakage Detection (EL0C)

Troubleshooting for refrigerant leakage detection (EL0C).

Indoor PCB/Display Board Communication Error (EH06)

Troubleshooting for indoor PCB/display board communication errors (EH06).

Current Overload Protection (PC08)

Troubleshooting for current overload protection (PC08).

IPM Malfunction or IGBT over-strong current protection (PC00)

Troubleshooting for IPM malfunction or IGBT over-current protection (PC00).

IPM Continuity Check

Procedure for checking IPM continuity.

Compressor Check

Procedure for checking compressor resistance.

Over voltage or low voltage protection (PC01)

Troubleshooting for over/low voltage protection (PC01).

Top temperature protection for compressor or High temperature or High pressure protection of IPM module (PC02)

Troubleshooting for compressor temp/IPM temp/high pressure protection (PC02).

Inverter compressor Drive Error (PC04)

Troubleshooting for inverter compressor drive errors (PC04).

Low Pressure Protection (PC03)

Troubleshooting for low pressure protection (PC03).

Indoor Units Mode Conflict (match with multi outdoor unit)

Describes mode conflicts between indoor units in multi-unit systems.

Communication Error Between Outdoor Main Chip and Compressor Driven Chip (PC40)

Troubleshooting for communication errors between outdoor main chip and compressor chip (PC40).

Check Procedures

Temperature Sensor Check

Procedure for checking temperature sensors using a multimeter.

Compressor Check

Procedure for checking compressor resistance values.

IPM Continuity Check

Procedure for checking IPM continuity.

4 - Way Valve Check

Procedure for checking the 4-way valve voltage and resistance.

EXV Check

Procedure for checking the Electronic Expansion Valve (EXV) winding resistance.

Main Parts Check

Temperature sensor checking

Procedure for checking temperature sensors and their resistance values.

Pressure on Service Port

System Pressure

DISASSEMBLY INSTRUCTIONS

Outdoor Unit Sizes 9-12K (115V) Panel Plate

Disassembly instructions for the outdoor unit panel plate.

Outdoor Unit Sizes 24K (208-230V)

Disassembly instructions for the outdoor unit panel plate (24K, 208-230V).

ELECTRICAL PARTS

PCB Board 2

PCB Board 3

PCB Board 4

PCB Board 5

PCB Board 6

PCB Board 7

PCB Board 8

PCB Board 9

PCB Board 10

PCB Board 11

PCB Board 12

Fan Assembly

Fan Motor

Steps to remove the fan motor.

Sound Blanket

Four Way Valve (for heat pump models)

Compressor

SAFETY CAUTION

Appendix 1

Appendix 2

Appendix 3