Carrier DHMVHA Service Manual

DHMVHA
High Wall Ductless System
Sizes 09 to 24

TABLE OF CONTENTS

SAFETY CONSIDERATIONS ....................................................... 1
INTRODUCTION............................................................................ 1
MODEL NUMBER NOMENCLATURE ....................................... 2
DIMENSIONS ................................................................................. 3
CLEARANCES................................................................................ 3
ELECTRICAL DATA ..................................................................... 4
WIRING ........................................................................................... 4
CONNECTION DIAGRAMS ......................................................... 5
WIRING DIAGRAM....................................................................... 6
REFRIGERATION CYCLE DIAGRAM........................................ 7
REFRIGERANT LINES .................................................................. 7
ELECTRONIC FUNCTIONS ......................................................... 8
MULTI-FUNCTION BOARD INSTRUCTION ............................. 12
TROUBLESHOOTING................................................................... 13
INDOOR UNIT DIAGNOSTIC GUIDE......................................... 14
DIAGNOSIS AND SOLUTION...................................................... 15
APPENDICES.................................................................................. 39
DISASSEMBLY INSTRUCTIONS ................................................ 42

SAFETY CONSIDERATIONS

Installing, starting up, and servicing air-conditioning equipment can
be hazardous due to unit 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 only.
When working on the equipment, observe the 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 the warnings or cautions
included in the literature and attached to the unit. Consult local
building codes and the 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 of hazards which will result in severe
PAGE
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.
ELECTRICAL SHOCK HAZARD
Failure to follow this warning could result in personal injury or death.
Before installing, modifying, or servicing the unit, the 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.
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 the extended periods of
unit shutdown. This causes refrigerant slugging and could possibly
.

INTRODUCTION

This service manual provides the necessary information to service,
repair, and maintain the indoor units. This manual contains with data
required to troubleshoot. Use the TABLE OF CONTENTS to locate a
desired topic.
Specifications subject to change without notice.
WARNING
WARNING
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.
CAUTION