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PRE-START-UP
IMPORTANT: Before beginning Pre-Start-Up or Start-Up,
review Start-Up Checklist at the back of this book. The
Checklist assures proper start-up of a unit and provides a
record of unit condition, application requirements, system
information, and operation at initial start-up.
CAUTION
UNIT DAMAGE HAZARD
Failure to follow this caution may result in equipment damage.
Do not attempt to start the heat pump system, even momentar-
ily, until the following steps have been completed. Compressor
damage may result.
System Check
1.
Check all indoor section and other equipment auxiliary com-
ponents. Consult the manufacturer's instructions regarding
any other equipment connected to the condensing unit. If the
unit has field-installed accessories, be sure all are properly
installed and correctly wired. If used, the airflow switch must
be properly installed.
2.
Be sure the unit is properly leak checked and dehydrated.
3.
Check tightness of all electrical connections.
4.
Open the liquid line and suction line service valves.
5.
Be sure the unit is properly charged. See "Preliminary
Charge", below.
6.
The electrical power source must agree with the unit's name-
plate rating.
7.
The crankcase heater must be firmly attached to the compres-
sor crankcase. Be sure the crankcase is warm (heater must be
on for 24 hours before starting compressor).
Turn On Crankcase Heater
Turn on the crankcase heater for 24 hours before starting the unit
to be sure all the refrigerant is out of the oil. To energize the crank-
case heater, proceed as follows:
1.
Set the space thermostat set point above the space tempera-
ture so there is no demand for cooling.
2.
Close the field disconnect.
Preliminary Charge
Before starting the unit, charge liquid refrigerant into the high side
of the system through the liquid service valve. The amount of re-
frigerant added must be at least 80% of the operating charge listed
in the Physical Data table (Tables 2 and 3 on pages 6 and 7).
Allow high and low side pressures to equalize before starting com-
pressor. If pressures do not equalize readily, charge vapor on low
side of system to assure charge in the evaporator. Refer to GTAC
II, Module 5, Charging, Recover, Recycling, and Reclamation for
liquid charging procedures.
CAUTION
UNIT DAMAGE HAZARD
Failure to follow this caution may result in equipment damage.
Prior to starting compressor, a preliminary charge of refriger-
ant must be added to avoid possible compressor damage.
38AUQ Units
The compressor crankcase heater must be on for 24 hours before
start-up. After the heater has been on for 24 hours, the unit can be
started. If no time elapsed since the preliminary charge step was
completed, it is unnecessary to wait the 24-hour period.
PRELIMINARY CHECKS
1.
Check that electric power supply agrees with unit nameplate
data.
2.
Verify that the compressor crankcase heater is securely in
place.
3.
Check that the compressor crankcase heater has been on at
least 24 hours.
4.
Recheck for leaks using the procedure outlined in the
Pre-Start-Up section, Leak Test and Dehydration. If any
leaks are detected, repair as required. Evacuate and
dehydrate as described in the Leak Test and Dehydration
section.
5.
Ensure that the preliminary charge has been added as
described in the Pre-Start-Up section, Preliminary Charge.
6.
All internal wiring connections must be tight, and all barri-
ers and covers must be in place.
NOTE: The units are factory charged with the required amount of
oil. If recharging in required, use Emkarate
COMPRESSOR ROTATION
On 3-phase units with scroll compressors, it is important to be cer-
tain that the compressor is rotating in the proper direction. 38AUQ
units are equipped with a Comfort Alert Diagnostic Module
(CADM). Alert Code 7 indicates reverse power phasing.
To correct phase order:
1.
Turn off power to the unit, tag disconnect.
2.
Reverse any two of the unit power leads.
3.
Reapply power to the compressor, verify correct pressures.
To verify the compressor is rotating in the proper direction:
1.
Connect service gauges to the suction and liquid pressure
fittings.
2.
Energize the compressor.
3.
The suction pressure should drop and the liquid pressure
should rise, as is normal on any start-up.
COMPRESSOR OVERLOAD
This overload interrupts power to the compressor when either the
current or internal motor winding temperature becomes excessive,
and automatically resets when the internal temperature drops to a
safe level. This overload may require up to 60 minutes (or longer)
to reset. If the internal overload is suspected of being open, discon-
nect the electrical power to the unit and check the circuit through
the overload with an ohmmeter or continuity tester.
ADVANCED SCROLL TEMPERATURE PROTECTION
(ASTP)
A label located above the terminal box identifies Copeland
Scroll compressor models that contain this technology. See
Fig. 14. Advanced Scroll Temperature Protection (ASTP) is a
form of internal discharge temperature protection, that unloads the
scroll compressor when the internal temperature reaches approxi-
mately 300°F. At this temperature, an internal bi-metal disk valve
opens and causes the scroll elements to separate, which stops com-
pression. Suction and discharge pressures balance while the motor
continues to run. The longer the compressor runs unloaded, the
longer it must cool before the bi-metal disk resets. See Fig. 15.
1. Third-party trademarks and logos are the property of their respective
owners.
17
START-UP
®1
RL 32-3MAF.
™1
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