17
Compressor Rotation
NOTE: When the compressor is rotating in the wrong direction,
the unit makes an elevated level of noise and does not provide
cooling.
On 3-phase units with scroll compressors, it is important to be
certain compressor is rotating in the proper direction. To deter-
mine whether or not compressor is rotating in the proper
direction:
1. Connect service gages to suction and discharge pressure
fittings.
2. Energize the compressor.
3. The suction pressure should drop and the discharge pres-
sure should rise, as is normal on any start-up.
NOTE: If the suction pressure does not drop and the discharge
pressure does not rise to normal levels, the evaporator fan is prob-
ably also rotating in the wrong direction.
4. Turn off power to the unit.
5. Reverse any two of the three unit power leads.
6. Reapply electrical power to the compressor. The suction
pressure should drop and the discharge pressure should
rise which is normal for scroll compressors on start-up.
7. Replace compressor if suction/discharge pressures are not
within specifications for the specific compressor.
The suction and discharge pressure levels should now move to
their normal start-up levels.
Filter Drier
Replace whenever refrigerant system is exposed to atmo-
sphere. Only use factory specified liquid-line filter driers with
working pressures no less than 650 psig. Do not install a suc-
tion-line filter drier in liquid line. A liquid-line filter drier de-
signed for use with Puron refrigerant is required on every unit.
Condenser-Fan Adjustment
1. Shut off unit power supply. Install lockout tag.
2. Remove condenser-fan assembly (grille, motor, and fan).
See Fig. 29.
3. Loosen fan hub setscrews.
4. Adjust fan height by pushing fan until it stops on the fan
shaft.
5. Tighten set screw to 60 in.-lb (6.78 Nm).
6. Replace condenser-fan assembly. When replacing the con-
denser-fan assembly follow the screw pattern sequence
shown in Fig. 30. The screws must be replaced in the
sequence shown in the figure.
Fig. 29 — Condenser Fan Adjustment
Fig. 30 — Condenser-Fan Assembly — Screw Pattern Sequence
CAUTION
EQUIPMENT DAMAGE HAZARD
Failure to follow this caution can result in premature wear
and damage to equipment.
Scroll compressors can only compress refrigerant if rotat-
ing in the right direction. Reverse rotation for extended
times can result in internal damage to the compressor.
Scroll compressors are sealed units and cannot be repaired
on site location.
1
2
3
4
5
NO SCREW
(Blank Tab)
Summary of Contents for 50FC A04 Series
Page 96: ...96 APPENDIX D WIRING DIAGRAMS Fig J 50FC 04 06 208 230 1 60 Unit with RTU Open Controller...
Page 97: ...97 APPENDIX D WIRING DIAGRAMS Fig K 50FC 04 06 208 230 3 60 Unit with RTU Open Controller...
Page 98: ...98 APPENDIX D WIRING DIAGRAMS Fig L 50FC 04 06 460 575 3 60 Unit with RTU Open Controller...
Page 99: ...99 APPENDIX D WIRING DIAGRAMS Fig M 50FC 07 208 230 Unit with RTU Open Controller...
Page 100: ...100 APPENDIX D WIRING DIAGRAMS Fig N 50FC 07 460 575 Unit with RTU Open Controller...
Page 101: ...101 APPENDIX D WIRING DIAGRAMS Fig O 50FC 04 06 Power Wiring Diagram 208 230 1 60...
Page 102: ...102 APPENDIX D WIRING DIAGRAMS Fig P 50FC 04 07 Power Wiring Diagram 208 230 3 60...
Page 103: ...103 APPENDIX D WIRING DIAGRAMS Fig Q 50FC 04 07 Power Wiring Diagram 460 575 3 60...
Page 104: ...104 APPENDIX D WIRING DIAGRAMS Fig R 50FC 04 06 SystemVu Control Wiring Diagram All Voltages...
Page 105: ...105 APPENDIX D WIRING DIAGRAMS Fig S 50FC 07 SystemVu Control Wiring Diagram All Voltages...
Page 106: ...106 APPENDIX D WIRING DIAGRAMS Fig T 50FC 04 06 SystemVu Power Wiring Diagram 208 230 1 60...
Page 107: ...107 APPENDIX D WIRING DIAGRAMS Fig U 50FC 04 07 SystemVu Power Wiring Diagram 208 230 3 60...
Page 108: ...108 APPENDIX D WIRING DIAGRAMS Fig V 50FC 04 07 SystemVu Power Wiring Diagram 460 575 3 60...