19XR (PIC II) Hermetic Centrifugal Liquid Chillers 50 Hz - Carrier

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42 Pressure on condenser vessel is at refrigerant saturated conditions (see refrigerant pressuretemperature tables 5A and 5D) Cooler pressure reading is 103 kPa or higher Record pressures Power up controls to ensure oil heater is on and oil is hot. Equalizer pressure between cooler and condenser No leaks found Perform leak test Leaks found Machines with refrigerant charge Leak test of 19XR 1 - Attach compound gauge -101-0-3000 kPa to each vessel 2 - Note ambient temperature gauge readings Pressure on condenser vessel is less than saturated refrigerant pressure (see refrigerant pressure-temperature tables 5A and 5D) Cooler pressure reading is below 103 kPa Leak suspected Record pressures Is either vessel at 0 kPa? Power up controls to ensure oil heater is on and oil is hot. Equalizer pressure between cooler and condenser Add refrigerant until pressure is above 241 kPa Leaks found Locate and mark all leak sources Recover refrigerant from vessel Repair all leaks No Perform leak test No leaks found Recover refrigerant from vessel Perform standing vacuum test Pass Fail Yes Dehydrate vessel if vessel was at atmospheric pressure or lower Fig. 25 - 19XR leak detection procedure Machines with nitrogen holding charge Pressure reading is less than 103 kPa but greater than 0 kPa Leak suspected Raise pressure to 483 kPa with nitrogen (if using electronic detector, add tracer gas now) Perform leak test using soap bubble solution, ultrasonics or electronic detector No leaks found Evacuate vessel Complete charging machine Leaks found Locate and mark all leak sources Release the pressure in the vessel Repair all leaks Retest only those joints that were repaired Pressure is at 103 kPa (factory charge) Release nitrogen and evacuate holding charge from vessels Add refrigerant until pressure is above 241 kPa Perform leak test Leaks found No leaks found
6. Valve off the vacuum pump, stop the pump, and record the instrument reading. 7. After a 2-hour wait, take another instrument reading. If the reading has not changed, dehydration is complete. If the reading indicates vacuum loss, repeat Steps 4 and 5. 8. If the reading continues to change after several attempts, perform a leak test up to the maximum 1103 kPa pressure. Locate and repair the leak, and repeat dehydration. 1. To vacuum pump 2. Mixture of dry ice and methyl alcohol 3. Moisture condenses on cold surface 4. From system 4.5 - Inspect Wiring Fig. 26 - Dehydration cold trap WARNING: Do not check voltage supply without proper equipment and precautions. Serious injury may result. Follow power company recommendations. CAUTION: Do not apply any kind of test voltage, even for a rotation check, if the chiller is under a dehydration vacuum. Insulation breakdown and serious damage may result. 1. Examine wiring for conformance to job wiring diagrams and to all applicable electrical codes. 2. On low-voltage compressors (600 V or less) connect voltmeter across the power wires to the compressor starter and measure the voltage. Compare this reading with the voltage rating on the compressor and starter nameplates. 3. Compare the ampere rating on the starter nameplate with the compressor nameplate. The overload trip amps must not be more than 108% of the rated load amps. 4. The starter for a centrifugal compressor motor must contain the components and terminals required for PIC II refrigeration control. Check certified drawings. 5. Check the voltage to the following components and compare to the nameplate values: oil pump contact, pumpout compressor starter, and control box. 6. Be sure that disconnects have been supplied for the oil pump, control box, and pumpout unit. 7. Check that all electrical equipment and controls are properly grounded in accordance with job drawings, certified drawings, and all applicable electrical codes. 8. Make sure that the customer’s contractor has verified proper operation of the pumps, cooling tower fans, and associated auxiliary equipment. This includes ensuring that motors are properly lubricated and have proper electrical supply and proper rotation. 9. For field-installed starters only, test the chiller compressor motor and its power lead insulation resistance with a 500-V insulation tester such as a megohmmeter. (Use a 5000-V tester for motors rated over 600 V.) Factorymounted starters do not require a megohm test. a. Open the starter main disconnect switch and follow lockout/tagout rules. b. With the tester connected to the motor leads, take 10second and 60-second megohm readings as follows: 6-Lead Motor -Tie all 6 leads together and test between the lead group and ground. Next tie leads in pairs, 1 and 4, 2 and 5, and 3 and 6. Test between each pair while grounding the third pair. 3-Lead Motor - Tie terminals 1, 2, and 3 together and test between the group and ground. - Divide the 60-second resistance reading by the 10second reading. The ratio, or polarization index, must be one or higher. Both the 10- and 60-second readings must be at least 50 megohms. - If the readings on a field-installed starter are unsatisfactory, repeat the test at the motor with the power leads disconnected. Satisfactory readings in this second test indicate the fault is in the power leads. NOTE: Unit-mounted starters do not have to be megohm tested. 10. Tighten up all wiring connections to the plugs on the ISM, 8-input, and CCM modules. 11. Ensure that the voltage selector switch inside the control box is switched to the incoming voltage rating. 12. On chillers with free-standing starters, inspect the control box to ensure that the contractor has fed the wires into the bottom of the panel. Wiring into the top of the panel can cause debris to fall into the contactors. Clean and inspect the contactors if this has occurred. 4.6 - Carrier Comfort Network Interface (see Fig. 21) The Carrier Comfort Network (CCN) communication bus wiring is supplied and installed by the electrical contractor. It consists of shielded, 3-conductor cable with metallic braiding. The system elements are connected to the communication bus in a daisy chain arrangement. The positive pin of each system element communication connector must be wired to the positive pins of the system element on either side of it; the negative pins must be wired to the negative pins; the signal ground pins must be wired to signal ground pins. To attach the CCN communication bus wiring, refer to the certified drawings and wiring diagrams. The wire is inserted into the CCN communications plug (J1) on the CVC module. 4.7 - Check Starter CAUTION: BE AWARE that certain automatic start arrange-ments can engage the starter. Open the disconnect ahead of the starter in addition to shutting off the chiller or pump. Use the instruction and service manual supplied by the starter manufacturer to verify that the starter has been installed correctly, to set up and calibrate the starter, and for complete troubleshooting information. 43
Page 1 and 2: 19XR (PIC II) Hermetic Centrifugal
Page 3 and 4: TABLE OF CONTENTS (cont'd) 4 - BEFO
Page 5 and 6: INITIAL START-UP CHECKLIST FOR 19XR
Page 7 and 8: 19XR HERMETIC CENTRIFUGAL LIQUID CH
Page 9 and 10: 1 - SAFETY CONSIDERATIONS 19XR liqu
Page 11 and 12: 2 - INTRODUCTION AND CHILLER FAMILI
Page 13 and 14: The control centre: registers coole
Page 15 and 16: 1. Rear motor bearing 2. Forward mo
Page 17 and 18: 3 - INSTALLATION 3.1 - Introduction
Page 19 and 20: 3.3.3 - Physical data Table 1 Motor
Page 21 and 22: Maximum and minimum heat exchanger
Page 23 and 24: 1. Hot gas bypass (cut) 2. Compress
Page 25 and 26: 3.4 - Install machine supports Typi
Page 27 and 28: 1. Air vent 2. Leaving condenser wa
Page 29 and 30: 1a. Safety valve on machine 1b. Saf
Page 31 and 32: The control cabinet (standard unit)
Page 33 and 34: Electrical characteristics of the m
Page 35 and 36: 3.6.4 - Make the necessary connecti
Page 37 and 38: Insulate Motor Terminals and Lead W
Page 39 and 40: 4 - BEFORE INITIAL START-UP 4.1 - N
Page 41: h. Slowly raise the system pressure
Page 45 and 46: The valve is opened counter-clockwi
Page 47 and 48: To return the chiller to normal con
Page 49 and 50: 49 Date: __________________________
Page 51 and 52: To pressurize with dry nitrogen Ano
Page 53 and 54: 7.3.5 - Refrigerant Filter A refrig
Page 55 and 56: X See view A Y See view B Z Thrust

19XR (PIC II) Hermetic Centrifugal Liquid Chillers 50 Hz - Carrier

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