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Anleitung Zusammenfassung
Loosen the compressor holddown bolts to allow free spring travel. Open the compressor suction and discharge service valves. Check that oil is visible in the compressor sight glass. Add oil if necessary. 56 Table 8 — Control Test Menu Functions See the Pumpout and Refrigerant Transfer Procedures TESTS TO BE PERFORMED 1. Automated Tests* 2. PSIO Thermistors 3. Options Thermistors 4. Transducers 5. Guide Vane Actuator 6. Pumps 7. Discrete Outputs 8. Pumpdown/Lockout 9. Terminate Lockout 10. FX Gear Oil Pump I/O DEVICES TESTED Operates the second through seventh tests Entering chilled water Leaving chilled water Entering condenser water Leaving condenser water Discharge temperature Bearing temperature Motor winding temperature Oil sump temperature Common chilled water supply sensor Common chilled water return sensor Remote reset sensor Temperature sensor — Spare 1 Spare 2 Spare 3 Spare 4 Spare 5 Spare 6 Spare 7 Spare 8 Spare 9 Evaporator pressure Condenser pressure Oil pressure differential† Open Close All pumps or individual pumps may be activated: Oil pump — Confirm pressure Chilled water pump — Confirm flow Condenser water pump — Confirm flow Auxiliary oil pump — confirm pressure† All outputs or individual outputs may be energized: Hot gas bypass relay Oil heater relay Motor cooling relay Tower fan relay Alarm relay Shunt trip relay When using pumpdown/lockout, observe freeze up precautions when removing charge. Instructs operator as to which valves to close and when. Starts chilled water and condenser water pumps and confirms flows. Monitors — Evaporator pressure Condenser pressure Evaporator temperature during pumpout procedures Turns pumps off after pumpdown. Locks out compressor. Starts pumps and monitors flows. Instructs operator as to which valves to open and when. Monitors — Evaporator pressure Condenser pressure Evaporator temperature during charging process Terminates compressor lockout. Activates gear main oil pump; confirms pressure. Activates optional gear auxiliary pump; confirms pressure. *During any of the tests that are not automated, an out-of-range reading will have an asterisk (*) next to the reading and a message will be displayed. †On open-drive chillers, differential pressure is the only oil pressure displayed. (page 63) and Pumpout System Maintenance sections (page 83) for details on transferring refrigerant, oil specifications, etc. High Altitude Locations — Because the chiller is initially calibrated at sea level, it is necessary to recalibrate the pressure transducers if the chiller is to be operated at a high altitude location. Please see the calibration procedure in the Troubleshooting Guide section. Charge Refrigerant into Chiller The transfer, addition, or removal of refrigerant in spring isolated chillers may place severe stress on external piping if springs have not been blocked in both up and down directions. The 17EX chiller may have the refrigerant already charged in the economizer/storage vessels. If chiller is not shipped fully charged, refrigerant is shipped separately to conform with transportation regulations. The 17EX may be ordered with a nitrogen holding charge of 15 psig (103 kPa). Evacuate the entire chiller, and charge chiller from refrigerant cylinders. The full refrigerant charge on the 17EX will vary with chiller components and design conditions as indicated on the job data specifications. An approximate charge may be found in Physical Data and Wiring Schematics section, page 99. The full chiller charge is printed on the chiller identification label. Always operate the condenser and chilled water pumps during charging operations to prevent water in heat exchanger tubes from freezing. Use the CONTROLS TEST terminate lockout function to monitor conditions and start the pumps. If the chiller has been shipped with a holding charge, add refrigerant through the refrigerant charging valve (Fig. 6) or to the pumpout charging connection. First evacuate the nitrogen holding charge from the vessels. Charge the refrigerant as a gas until the system pressure exceeds 35 psig (141 kPa). After the chiller is beyond this pressure, the refrigerant should be charged as a liquid until all the recommended refrigerant charge has been added. TRIMMING REFRIGERANT CHARGE — The 17EX is shipped with the correct charge for the design duty of the chiller. Trimming the charge can best be accomplished when the chiller is operating at design load. To trim, check the temperature difference between the leaving chilled water temperature and the cooler refrigerant temperature at full load design conditions. If necessary, add or remove refrigerant to bring the temperature difference to design conditions or a minimum differential. INITIAL START-UP Preparation — Before starting the chiller, check that the: 1. Power is on to the main starter, oil pump relay (which energizes both the compressor and gear oil pumps), tower fan starter, oil heater relay, and the chiller control center. 2. Cooling tower ...