Carrier 38AH024-034 - Manual

HEATING & COOLING
38AH024-034
Air-Cocled Condensing Units
50/60 Hz
Installation, Start-up and Service
Instructions
CONTENTS
SAFETY CONSIDERATIONS .. .
Page
............................. 1
BEFORE INSTALLATION ................................ 1-5
Rigging .............................................................. 1
Placing Unit ....................................................... 1
Mounting Unit .................................................... 5
Compressor Mounting ....................................... 5
INSTALLATION .............................................. 5-13
Refrigerant Piping Connections......................... 5
Solenoid Drop Refrigerant Control..................... 5
Filter Drier and Moisture Indicator...................... 5
Receiver ............................................................ 5
Piping Procedure ............................................... 5
Power Supply .................................................... 7
Power Wiring ..................................................... 7
PRE-START-UP ................................................ 14
System Check ................................................... 14
Leak Test and Dehydration............................... 14
Preliminary Charge ........................................... 14
START-UP....................................................... 14-16
Preliminary Checks ........................................... 14
Preliminary Oil Charge ...................................... 14
Start Unit ........................................................... 14
Adjust Refrigerant Charge................................ 15
Check Compressor Oil Level............................ 15
Final Checks..................................................... 15
SEQUENCE OF OPERATION......................... 17
Single Air Handler —
2-Stage Cool Thermostat ............................... 17
Two Air Handlers —
Two 2-Stage Cool Thermostats
(One Per Air Handler) .................................... 17
Restart.............................................................. 17
Causes of Complete Unit Shutdown ................. 17
SERVICE ....................................................... 18-20
Access for Servicing .......................................... 18
Fan Adjustment ................................................. 18
Oil Charge ......................................................... 18
Liquid Shutoff/Charging Valve .......................... 18
Capacity Control, Suction Pressure-
Actuated Unloaders ....................................... 18
Capacity Control, Electrically Operated
Unloaders (Variable Air Volume
Factory-Installed Option Units) ......................
18
Oil Pressure Safety Switch (OPS).................... 18
Compressor Protection ..................................... 18
High-Pressure Switches................................... 18
Low-Pressure Switches .................................... 18
Winter Start Control ........................................... 20
Head Pressure Control ..................................... 20
TROUBLESHOOTING..................................... 21-23
START-UP CHECKLIST ..................... CL-1, CL-2
SAFETY CONSIDERATIONS
Installing, starting up, and servicing air-conditioning equip­
ment can be hazardous due to system pressures, electrical
components, and equipment location (roofs, elevated struc­
tures, etc.)
Only trained, qualified installers and service mechanics
should install, start up, and service this equipment (Fig. 1).
Untrained personnel can perform basic maintenance func­
tions 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.
• See Table lA or IB for Physical Data.
S ilii ELECTRIC SHOCK HAZARD
¿5 Open all remote disconnects before ser­
vicing this equipment.
BEFORE INSTALLATION
Rigging — Preferred method is with spreader bars from
above the unit. Use 2-in. (50 mm) OD pipe or hooks in lift­
ing holes. Rig with 4 cables and spreader bars. All panels
must be in place when rigging. See rigging label on unit for
details concerning shipping weights, distance between lift­
ing holes, center of gravity, and spreader bar dimensions.
See Fig. 2.
If overhead rigging is not possible, place condensing unit
on skid or pad for rolling or dragging. When rolling, use
minimum 3 rollers. When dragging, pull the pad. Do not
apply force to the unit. When in final position, raise from
above to lift unit off pad.
A CAUTION
All panels must be in place when rigging. Do not fork
units if no skid is supplied. If unit has skid, truck from
sides only.
Placing Unit — There must be 4 ft (1200 mm) for ser­
vice and for unrestricted airflow on all sides of unit, and a
minimum of 8 ft (2440 mm) clear air space above unit. For
multiple units, allow 8 ft (2440 mm) separation between
units for airflow and service.
Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.
Book 11 PC 111 Catalog No 563-739 Printed in U.S A Form 38AH-7SI Pg 1 4-93 Replaces: New
Tab 3a