Carrier 48/50PD05 User Manual

6BASEPAN CONNECTIONSACCESS PANELFILTER ACCESS DOORGAS SECTIONACCESSCONDENSER COILACCESS PANELINDOOR MOTORACCESS DOORCONTROL BOXANDCOMPRESSORELECTRICALOPTIONS PANELOUTDOOR AIRSCREEN(HIDDEN)C07002Fig. 4 -- Panel and Filter LocationsOn 3-phase units, it is important to be certain the compressors arerotating in the proper direction. To determine whether or notcompressors are rotating in the proper direction, use aphase-rotation meter on the unit input power to check forL1-L2-L3 or clockwise rotation or use the Service Test mode toenergize a compressor. If the compressor is rotating in the wrongdirection, the controls will stop the compressor and display alarmfor “Circuit A Failure to Pressurize.”IMPORTANT: Indoor or outdoor fan rotation direction may notindicate proper input power phase sequence, as some 3-phase unitsuse single-phase fan motors.To correct the wrong compressor rotation direction, perform thefollowing procedure:1. Turn off power to the unit and lock out the power.2. Switch any two of the incoming unit power leads.3. Turn on power to the unit.4. Verify corrected compressor rotation.Power SupplyAll 208/230-v units are factory wired for 230-v power supply. Ifthe 208/230-v unit is to be connected to a 208-v power supply, thetransformers (TRAN1 and TRAN2) must be rewired by movingthe wire from the 230-volt connection and moving to the 200-voltterminal on the primary side of the transformer. Refer to unit labeldiagram for additional information.Internal WiringCheck all electrical connections in unit control boxes; tighten asrequired.Evaporator FanFan belt and variable pulleys are factory--installed, but may need tobe adjusted for specific applications. Be sure that the fans rotate inthe proper direction. See Appendix C for unit specific fanperformance data. See Appendix D for unit specific air qualitylimits, evaporator fan motor specifications, FIOP static pressures,and fan RPM for various motor pulley settings. Appendix C and Dare based on 100% fan speed (VFD at 60Hz). To alter fanperformance, see Evaporator Fan Performance Adjustment in theService section.The Supply Fan Minimum Speed(Configuration→UNIT→FS.MN) and the Supply Fan MaximumSpeed (Configuration→UNIT→FS.MX) can also be used to alterfan performance. The fan should run at the maximum fan speedwhen setting up the application design point. The unit is equippedwith a Variable Frequency Drive (VFD). The VFD’s settingsshould not be used for adjusting fan performance. Specific VFDinformation can be found in Appendix B.IMPORTANT: When setting up and starting the unit, the heatingminimum CFM requirements must be upheld when changing belts,pulleys, and configurations. During heating mode, the fan speed isalways set to Supply Fan Maximum Speed (FS.MX).Condenser Fans and MotorsCondenser fans and motors are factory set. Refer to Condenser-FanAdjustment section as required.Return--Air FiltersCheck that correct filters are installed in filter tracks (see PhysicalData table in Installation Instructions). Do not operate unit withoutreturn-air filters.IMPORTANT: For units with 4-in. filter option, units are shippedwith standard 2-in. filters. To install 4-in. filters, the filter spacersmust be removed.Outdoor--Air Inlet ScreensOutdoor-air inlet screens must be in place before operating unit.48/50PD