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RT-SVX51L-EN
5. Restore the main electrical power and recheck the
phasing. If the phasing is correct, open the disconnect
switch or circuit protection switch and remove the
phase sequence indicator.
Compressor Crankcase Heaters
NOTICE
Compressor Failure!
Failure to follow instruction below could result in
compressor failure.
Unit must be powered and crankcase heaters
energized at least 8 hours BEFORE compressors are
started.
Each compressor can be equipped with a crankcase
heater. The proper operation of the crankcase heater is
important to maintain an elevated compressor oil
temperature during the “Off” cycle to reduce oil foaming
during compressor starts. Oil foaming occurs when
refrigerant condenses in the compressor and mixes with
the oil. In lower ambient conditions, refrigerant migration to
the compressor could increase.
When the compressor starts, the sudden reduction in
crankcase pressure causes the liquid refrigerant to boil
rapidly causing the oil to foam. This condition could
damage compressor bearings due to reduced lubrication
and could cause compressor mechanical failures.
Before starting the unit in the “Cooling” mode, set the
system switch to the “Off” position and turn the main power
disconnect to the “On” position and allow the crankcase
heater to operate a minimum of 8 hours.
Before closing the main power disconnect switch, insure
that the “System”selection switch is in the “Off” position and
the “Fan” selection switch is in the “Auto” position.
Close the main power disconnect switch and the unit
mounted disconnect switch, if applicable.
Checklist
Use the following checklist in conjunction with the general
checklist (
“General Unit Requirements,” p. 18
) to ensure
that the unit is properly installed and ready for operation.
WARNING
Hazardous Voltage!
Failure to disconnect power before servicing could
result in death or serious injury.
Disconnect all electric power, including remote
disconnects before servicing. Follow proper lockout/
tagout procedures to ensure the power can not be
inadvertently energized. Verify that no power is
present with a voltmeter.
☐
Check all electrical connections for tightness and “point
of termination” accuracy.
☐
Verify that the condenser airflow is unobstructed.
☐
Verify that the condenser fan and indoor blower turn
freely without rubbing and are properly tightened on the
shafts.
☐
Check the supply fan belts for proper tension and the
fan bearings for sufficient lubrication. If the belts require
adjustment, or if the bearings need lubricating, refer to
the maintenance section of this manual for instructions.
☐
Verify that a condensate trap is installed and the piping
is properly sized and pitched.
☐
Verify that the correct size and number of filters are in
place.
☐
Inspect the interior of the unit for tools and debris and
install all panels in preparation for starting the unit.
Factory-Mounted Unit Options
Unit Disconnect (FIYUDC)
WARNING
Hazardous Voltage w/Capacitors!
Failure to disconnect power and discharge capacitors
before servicing could result in death or serious
injury.
Disconnect all electric power, including remote
disconnects and discharge all motor start/run
capacitors before servicing. Follow proper lockout/
tagout procedures to ensure the power cannot be
inadvertently energized. Verify with a CAT III or IV
voltmeter rated per NFPA 70E that all capacitors have
discharged.
WARNING
Proper Field Wiring and Grounding
Required!
Failure to follow code could result in death or serious
injury.
All field wiring MUST be performed by qualified
personnel. Improperly installed and grounded field
wiring poses FIRE and ELECTROCUTION hazards. To
avoid these hazards, you MUST follow requirements
for field wiring installation and grounding as
described in NEC and your local/state/national
electrical codes.
Important:
All phases of this installation must comply with
NATIONAL, STATE, and LOCAL CODES. In
addition to local codes, the installation must
comply with National Electric Code - ANSI/
NFPA NO. 70 LATEST REVISION.
1. Field connections are made by first removing the
compressor access panel on the front of the unit.
Unscrew the assembly around the outside of the
disconnect switch. This assembly is located in the
condenser section of the unit.
Both high and low voltage power can be routed through
