20
Step 9 — Wind Baffles for Low Ambient Control
Models 569J***B and 569J***E include the factory installed
32LT Motormaster Low Ambient Control. Model 569J*12F (with
hot gas bypass option) also includes the 32LT Motormaster Low
Ambient Control as a standard feature.
Units with 32LT Motormaster control require the addition of wind
baffles to ensure full range low ambient operation. Material data
and dimensions for wind baffles are included in the Appendix C
section, Low Ambient Control, starting on page 50. Fabricate the
wind baffles and mount per instructions.
PRE-START-UP
System Check
1. The electrical power source must agree with the unit’s
nameplate rating.
2. Check all air handler(s) and other equipment auxiliary
components. Consult the manufacturer’s instructions
regarding any other equipment connected to the condens-
ing 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.
3. Check tightness of all electrical connections.
4. Be sure liquid line and low side of the system are properly
leak checked and dehydrated.
5. Be sure the unit is properly charged. See “Preliminary
Charge”, below.
6. Open the liquid line and suction line service valves.
7. The crankcase heater must be firmly attached to the com-
pressor 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 crankcase heater, proceed as follows:
1. Set the space thermostat set point above the space tem-
perature 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 refrigerant added must be at least 80% of the operating
charge listed in the Physical Data table (Tables 5 and 6). Allow
high and low side pressures to equalize before starting com-
pressor. If pressure 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 Recla-
mation for liquid charging procedures.
START-UP
The compressor crankcase heater must be on for 24 hours be-
fore 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 name-
plate 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 dehy-
drate 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 569J units are factory charged with the required
amount of oil. If recharging is required, use Emkarate
RL 32-3MAF for the 569J units.
COMPRESSOR ROTATION
On 3-phase units with scroll compressors, it is important to be
certain that the compressor is rotating in the proper direction.
569J units are equipped with a Comfort Alert Diagnostic Mod-
ule (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 gages 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 tempera-
ture 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, disconnect the electrical power to the unit and
check the circuit through the overload with an ohmmeter or con-
tinuity tester.
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 condensing unit, even momen-
tarily, until the following steps have been completed. Com-
pressor damage may result.
CAUTION
UNIT DAMAGE HAZARD
Failure to follow this caution may result in equipment
damage.
Prior to starting compressor, a preliminary charge of refrig-
erant must be added to avoid possible compressor damage.
