START UP
IMPORTANT INSTALLER NOTE
For improved
HIGH PRESSURE SWITCH
The WA372 models are supplied with a remote reset high pressure switch. If tripped, this pressure switch may be reset by turning the thermostat off then back on again.
THREE PHASE SCROLL COMPRESSOR START UP INFORMATION
Scroll compressors, like several other types of compressors, will only compress in one rotational direction. Direction of rotation is not an issue with single phase compressors since they will always start and run in the proper direction.
However, three phase compressors will rotate in either direction depending upon phasing of the power. Since there is a
Verification of proper rotation must be made any time a compressor is change or rewired. If improper rotation is corrected at this time there will be no negative impact on the durability of the compressor. However, reverse operation for over one hour may have a negative impact on the bearing due to oil pump out.
NOTE: If compressor is allowed to run in reverse rotation for several minutes, the compressor's internal protector will trip.
All three phase ZR3 compressors are wired identical internally. As a result, once the correct phasing is determined for a specific system or installation, connecting properly phased power leads to the same Fusite terminal should maintain proper rotation direction.
Verification of proper rotation direction is made by observing that suction pressure drops and discharge pressure rises when the compressor is energized.
Reverse rotation also results in an elevated sound level over that with correct rotations, as well as, substantially reduced current draw compared to tabulated values.
The direction of rotation of the compressor may be changed by reversing any two line connections to the unit.
PHASE MONITOR
All units with three phase compressors are equipped with a 3 phase line monitor to prevent compressor damage due to phase reversal.
The phase monitor in this unit is equipped with two LEDs. If the Y signal is present at the phase monitor and phases are correct the green LED will light.
If phases are reversed, the red fault LED will be lit and compressor operation is inhibited.
If a fault condition occurs, reverse two of the supply leads to the unit. Do not reverse any of the unit factory wires as damage may occur.
SERVICE HINTS
1.Caution homeowner to maintain clean air filters at all times. Also, not to needlessly close off supply and return air registers. This reduces airflow through the system, which shortens equipment service life as well as increasing operating costs.
2.Check all power fuses or circuit breakers to be sure they are the correct rating.
3.Periodic cleaning of the outdoor coil to permit full and unrestricted airflow circulation is essential.
SEQUENCE OF OPERATION
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