Service
Outdoor Fan— A reinforced wire mount holds the outdoor fan assembly in place.
Compressor Pressure Relief Valve — Valve is located in compressor. Relief valve opens at a pressure differential of
approximately 600 ± 50 psig between suction (low side) and discharge (high side) to allow pressure equalization.
Internal Current and Temperature Sensitive Overload — Control resets automatically when internal compressor
motor temperature drops to a safe level (overloads may require up to 45 minutes to reset). When an internal
overload is suspected of being open, check by using an ohmmeter or continuity tester. If necessary, refer to Carrier
Standard Systems Techniques Manual, Chapter 2, for complete information.
Pump down Procedure — Service valves provide a convenient shut-off valve useful for certain refrigeration system
repairs. System may be pumped down to make repairs on low side without losing complete refrigerant charge.
1. Attach pressure gage to suction service valve gage port.
2. Front seat the liquid line valve.
3. Start unit in cooling mode. Run until low-pressure switch opens at 54 psig (472Kpa). Do not allow compressor
to pump to a vacuum.
4. Shut unit off and front seat suction valve.
5. Depressurize low side of unit and recover refrigerant following accepted practice.
Filter Drier – The filter drier is specifically designed to operate with R-410A, use only factory-authorized components.
When removing a filter drier, use a tubing cutter to cut drier from system.
Do not unsweat a filter drier
from system.
Heat from unsweating will release moisture and contaminants from drier into the system.
Loss of Charge Pressure Switch — This switch, mounted on the suction line, has fixed non-adjustable settings. To
check pressure switch, attach pressure gage to suction service valve gage port. Slowly close liquid shutoff valve and
allow compressor to pump down. Do not allow compressor to pump down below 2 psig. Compressor should shut
down when suction pressure drops to cutout pressure in Physical Data Table, and should restart when pressure
builds up to cut-in pressure shown in Physical Data Table.
High Pressure Switch — This switch, mounted on the discharge line, has fixed non- adjustable settings & auto
reset. To check pressure switch, attach pressure gauge to compressor discharge service port, block condenser coil,
monitor pressure till compressor trips, remove blockage and observe at which pressure compressor restarts.
The 38C unit coils hold only the factory designated amount of refrigerant. Additional refrigerant may cause
units to relieve pressure through compressor internal pressure relief valve (indicated by sudden rise of suction
pressure) before suction pressure reaches 5 pisg. If this occurs, shut off immediately, then front seat the
suction valve and remove and recover excess refrigerant following accepted practice.
Caution
Before performing service or maintenance, be sure the indoor unit main power switch is off and indoor blower
has completely stopped. Failure to do so may result in electrical shock or injury from rotating fan blades.
Warning
Do not leave system open to atmosphere. Product damage could occur. Compressor oil is highly susceptible to
moisture absorption.
Caution
The compressor used in this product is specifically designed to operate with R-410A refrigerant and cannot be
interchanged.
Caution
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Содержание 38C Series
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