Carrier 38MBRC Series Service Manual

38MBRC
Outdoor Unit Single Zone Ductless System
Sizes 36 to 58

TABLE of CONTENTS

SAFETY CONSIDERATIONS ....................................................... 1
INTRODUCTION............................................................................ 1
MODEL / SERIAL NUMBER NOMENCLATURES .................... 2
WIRING ........................................................................................... 3
CONNECTION DIAGRAM............................................................ 4
WIRING DIAGRAMS..................................................................... 5
REFRIGERATION CYCLE DIAGRAM........................................ 7
REFRIGERANT LINES .................................................................. 8
SYSTEM EVACUATION AND CHARGING ............................... 9
SYSTEM VACUUM AND CHARGE ............................................ 9
ELECTRONIC FUNCTIONS ......................................................... 10
TROUBLESHOOTING................................................................... 15
DIAGNOSIS AND SOLUTION...................................................... 16
DIAGNOSIS AND SOLUTION...................................................... 18
DISASSEMBLY INSTRUCTIONS ................................................ 38
DISASSEMBLY INSTRUCTIONS ................................................ 42
APPENDICIES ................................................................................ 55

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
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.
Service Manual
These words are used with the safety-alert symbol. DANGER
identifies the most serious hazards which will result in severe personal
PAGE
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.
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.
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 38MBRC family of heat pumps. Use the
"TABLE of CONTENTS" on page 1 to locate a desired topic. For
detailed information regarding product specifications refer to product
data documentation.
Specifications subject to change without notice.
WARNING
WARNING
CAUTION