Carrier 38GNA - Manual

HEATING & COOUNG
38GNA
Air Conditioning Unit
instaliation and Start-up instructions
NOTE: Read the entire instruction manual before starting the
installation.
SAFETY CONSIDERATIONS
Improper installation, adjustment, alteration, service, maintenance,
or use can cause explosion, fire, electrical shock or other condi­
tions which may cause personal injury or property damage.
Consult a qualified installer, service agency, or your distributor or
branch for information or assistance. The qualified installer or
agency must use factory-authorized kits or accessories when
modifying this product. Refer to the individual instructions pack­
aged with the kits or accessories when installing.
Follow all safety codes. Wear safety glasses and work gloves. Use
quenching cloth for brazing operations. Have fire extinguisher
available. Read these instructions thoroughly and follow all
warnings or cautions attached to the unit. Consult local building
codes and National Electrical Code (NEC) for special require­
ments.
It is important to recognize safety information. This is the safety-
alert symbol /îy . When you see this symbol on the unit and in
instructions or manuals, be alert to the potential for personal
injury.
Understand the signal word DANGER, WARNING, or CAU­
TION. These words are used with the safety-alert symbol. DAN­
GER identifies the most serious hazards which will result in severe
personal injury or death. WARNING signifies hazards that could
result in personal injury or death. CAUTION is used to identify
unsafe practices which would result in minor personal injury or
product and property damage.
A WARNING
Before installing or servicing system, always turn off main
power to system. There may be more than 1 disconnect
switch. Turn off accessory heater power if applicable. Elec­
trical shock can cause personal injury or death.
GENERAL
Intake and discharge are on front of the unit. A minimum service
access distance of 30 in. behind unit must be provided.
NOTE: Refer to unit rating plate for ratings. '
This condensing unit is designed for use with evaporator coils or
fan coils equipped with capillary tube or piston-type refrigerant
control device. It may also be used with evaporators which have
expansion valves that equalize pressure during the off cycle or
hard shut-off expansion valves. The 018 size with hard shut-off
expansion valve requires a hard start kit.
BEFORE INSTALLATION
Check power supply: voltage, frequency and phase must corre­
spond with data on unit rating plate. Power supply must be able to
handle the additional load imposed by this equipment.
The 38GNA does not have a transformer. Therefore, the furnace
transformer (or another source) must be used as a low-voltage
supply. Transformer must have an additional capacity of 15 va
above the requirement of furnace or air handler.
The 024 size is equipped with a time-delay device which prevents
restart within 5 minutes of power interruption.
Compressor motor is equipped with an internal protector. Exces­
sive current or temperature causes protector to open which gives
indication of an open circuit in motor winding. Sufficient time
should be allowed for overload to reset before assuming compres­
sor has an open winding.
Compressor motor is designed to start under low-load conditions
only. Make sure system pressures have equalized before attempt­
ing to start unit. Equalization takes approximately 3 minutes.
Owner should be informed not to short-cycle unit with thermostat
as this causes compressor to trip out on overload.
Each unit is shipped with refrigerant charge adequate for use with
matching coils and refrigerant tubing kits. Charge is adequate for
systems using 25 ft of interconnecting tubing. See unit rating plate
for charge quantity. See Refrigerant Charging section and Table 2
for adjustment requirements.
A WARNING
Relieve all pressure before refrigerant system repair or final
unit disposal to avoid personal injury or death. Use all service
ports and open all flow control devices, including solenoid
valves.
A CAUTION
Do not vent refrigerant to atmosphere. Recover during system
repair or final unit disposal.
NOTE: Check indoor coil piston to see if it matches the required
piston shown on unit rating plate. If it does not match, replace
indoor coil piston with piston shipped with this unit. The piston
shipped with outdoor unit is correct for any approved indoor coil
combination.
Table 1—Installation Data (In.)
38GNA 018 024
Through-the-Wall
Clearance Dim.
26-1/2 X 29
Air Clearance 36
Concrete Mounting
Pad Dim.
27 X 17 X 5
Service Clearance*
Sides 0
Back 30
’Unit is serviced through rear access panel. Therefore, unit can be installed
with 0-in. end clearance.
INSTALLATION
Install condensing unit either through-the-wall, outdoors on a slab
or on the roof. When installing, allow sufficient space for airflow
clearance, wiring, refrigerant piping and servicing. Consult local
building codes and National Electrical Code (NEC) for special
installation requirements. See Fig. 1, 2 and 3 and Table 1 for
detailed installation data.
Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obiigations.
Book] 1 I 4 PC 101 Catalog No. 563-712 Printed in U.S.A. Form 38GNA-2SI Pg 1 11-92 Replaces: 38GNA-1 SI
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