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LG RCWW-1 Operation & Maintenance Manual

Water-cooled screw r134a
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Water-cooled Screw R134a
• Please read this Operation & Maintenance Manual completely before Operating &
Maintenance the product.
• Operating & Maintenance must be performed in accordance with the national wiring
standards by authorized personnel only.
• Please retain this Operating & Maintenance for future reference after reading it thoroughly.
MODELS: RCWW-1 Compressor
P/NO : MFL63281107



  Related Manuals for LG RCWW-1

  Summary of Contents for LG RCWW-1

  • Page 1 Maintenance the product. • Operating & Maintenance must be performed in accordance with the national wiring standards by authorized personnel only. • Please retain this Operating & Maintenance for future reference after reading it thoroughly. MODELS: RCWW-1 Compressor P/NO : MFL63281107...
  • Page 2: Table Of Contents

    Water cooled Screw Operation & Maintenance Manual TABLE OF CONTENTS WARNING/CAUTION Warning...........................3 Caution............................7 GENERAL HMI (Human Machine Interface) Operation ................11 CONTROLS Control Panel ........................25 PLC and HMI Unit .........................26 Power Panel..........................33 Machine On/Off Control ......................34 START UP Pre Start-up ..........................35 Operating Procedure ......................36 Operation Limit........................37 OPERATION...
  • Page 3 Improper use operation of the product that does not comply with the directions described in the manual can lead to injury or damage. The severity is classified as follows. n LG is not responsible for problems out of the warranty period, problems from mishandling by the consumer, problems from natural disaster and power cord defect.
  • Page 4 Do not disassemble, repair or reconfigure the The product must be grounded properly. product on your own. • It can cause a fire and electric shock. • If not grounded properly, it can cause electric shock. Do not store or use combustible gas or flam- Do not reconfigure or change the setting of mable substance near the product.
  • Page 5 When explosive has leaked, immediately lock Do not operate the circuit breaker or main the valve and open the window to ventilate the power switch with wet hands. room before operating the product. • At this time, do not use the telephone or the •...
  • Page 6 Indicate and check all switches blocked • If you would like to use a substitute refrigerant, so that the power will not be recovered until the please contact LG. task is completed. Wear protective gear. When providing the service, do not take off the brazing on the existing joint.
  • Page 7 After installing or repairing the product, Do not install the product at a location where always check for gas leakage. combustible gas is leaking. • It can cause problems to the product. • It can cause property damage. When installing the product, make sure to Do not install the product for special level the product.
  • Page 8 Check whether the installation board has been Safely remove the packaging. damaged from long use. • When the base breaks down, the product can fall • Metal objects such as nail or other wooden pack- over to cause property damage, problem in prod- aging can cause skin cut or other injury.
  • Page 9 • LG is not responsible for any damage in chiller • Insufficient check can cause a fire, an explosion and condenser from unprocessed or inappropri- or a problem.
  • Page 10 Welding the evaporator head or nozzle part is Install the device only on the heat exchanger. not recommended. • When you need to weld a part, you must remove • When the device is installed on the lower heat the flux switch and coolant water inlet/outlet ther- exchanger, the device may not be lifted safely.
  • Page 11: General

    GENERAL This manual consists of information about control, operation, start, service and problem solving of water-cooling chiller. n HMI (Human Machine Interface) Operation You should not change the program without consulting LGE service agent. Wrong program can harm the machine. Fig.
  • Page 12 Main Display Fig. 2 Main Display consists of one screen, and it is the screen showing up when power is ON in the first stage. Operator can check the present condition of chiller in Main display. Also, operator can start/stop in main display.
  • Page 13 Alarm History Fig. 3 Last operated alarm will be indicated on Alarm display with time. Also, operator can cancel alarm on the screen. See the Fig4 below for cancellation of alarm. Alarm elimination (Reset) Alarm elimination (Reset) Clear Cancellation Done Fig.
  • Page 14 User Setting Fig. 5 Chiller Water-cooled Screw - 14 -...
  • Page 15 User setting consists of 2 screens. Movement can be done with clicking arrow ▽, △ Through user setting, operator can make up the control parameter of chiller. Operator basically can check and change the control setting condition of cold water outlet tempera- ture.
  • Page 16 Function Setting Fig. 6 Chiller Water-cooled Screw - 16 -...
  • Page 17 Function setting menu consists of 3 screens, and screen movement can be done by using arrow ▽, △. Operator can set the present time in the first screen. It can be done by selecting date and time box which operator wants. Resting 2nd screens enable operator to set the operation schedule of chiller.
  • Page 18 I/O Display Chiller Water-cooled Screw - 18 -...
  • Page 19 Fig. 7 Input/Output display consists of total 5 screens including 3 screens for expressing the input condi- tion and 2 screens for expressing the output condition. Input/Output display has input information that means switch data that chiller control is inputted, and output information that means output sig- nal approval of load equipment that conduct chiller controller output.
  • Page 20 Input Normal Indication Meaning condition Normal condition when when operating stopping M1 Contactor Main electron contactor Electron contactor for △ short OFF → ON M2 Contactor ON → OFF M3 Contactor Electron contactor for Y short Oil Flow Oil flow switch (in 5 minutes of operation) Oil Level Oil Level switch...
  • Page 21 Compressor interior protector is equipment for sensing winding wire and discharge temperature of com- pressor which is installed on compressor. In case that compressor interior protector sense abnormal high temperature from winding wire and discharge temperature, this signal change from ON to OFF, it is kept ON in normal temperature condition.
  • Page 22 M1 contactor, M2 contactor and M3 contactor indicates condition of electron contactor for compres- sor with input display. The value indicated on Output display is Output from actual PLC, the value indicated on Input display is extra contact part condition which is inputted to PLC from electron con- tactor.
  • Page 23 Running Information Fig. 8 - 23 - Operation & Maintenance Manual...
  • Page 24 Operation Information screen indicates operation value state of chiller including chilling cycle, cold water/cooling water temperature. This operation value state includes chiller operation capability and operation current in present con- dition, also does accumulate operation time of cold water, cooling water pump and compressor. Also, operation value state indicates refrigerant temperature of chilling cycle and cold water, cooling water temperature.
  • Page 25: Controls

    CONTROLS n Control Panel Relay Current Transducer Touch Panel Fuse Manual/Remote SMPS Power Lamp control switch Emergency Switch Fig. 9 Inside of control panel, PLC(Programmable Logic Controller) which is actual Main controller and other related components are located. PLC controls compressor and volume control valve through outlet port sensing sensor and switch condition through input port.
  • Page 26: Plc And Hmi Unit

    CONTROLS Relay is used to recognize the control switch condition and Current Transducer helps to change Current value which is recognized by CT(Current Transformer) to signal that PLC can recognize. HMI which has touch panel for user interface is installed to door of control panel, it indicates power approval through power lamp.
  • Page 27 OUT2 OUT2 AIN1 AIN1 AIN2 AIN2 OUT1 OUT1 Fig. 11 Fig. 11 describes input/output port composition of PLC. All input/output signal for chiller control is connected to PLC, it is delivered to PLC as input or it is approved output from PLC. Used input/output for this product among input/output of PLC is shown below.
  • Page 28 DIP switch and indication LED is installed on the top of PLC. Normally D2 LED should be flicker- ing as 4Hz frequency, D3~D6 should be OFF. Other LED is flickering depending on PLC commu- nication condition. 4-position DIP switches should be OFF, 8-position DIP switch should indicates MODBUS slave equipment address.
  • Page 29 Connector Wire No. Description 220V AC-L 220V AC-N Frame Ground 1#Main contactor, Oil separator sol. Valve Contactor 1# Y Contactor 1# Loading Electrovalve OUT1 1# Unloading Electrovalve 1# 75% Electrovalve 1# Oil Recover Valve Common : 220V AC Live Tower Fan OUT2 Cooling Water Pump Chilled Water Pump...
  • Page 30 Connector Wire No. Description 1#Main contactor Contactor 1# Y Contactor 1# Oil flow switch Oil level switch Oil Pressure differential switch 1#Interior protection equipment Power phase sequence monitor equipment 1# Compressor overload relay High-pressure switch Low-pressure switch Freeze and burst prevention switch Water pump contactor input Cold water/ cooling water flow switch Emergency stop switch...
  • Page 31 Connector Wire No. Description AI1+ Cooling water outlet temperature AI1- AI2+ Cooling water inlet temperature AI2- AI3+ Chilled water outlet temperature AI3- AIN1 AI4+ Chilled water inlet temperature AI4- AI5+ 1# Compressor discharge temperature AI5- AI6+ 2# Compressor discharge temperature AI6- AI7+ AIN2...
  • Page 32 MODBUS address map is shown in the table below. MODBUS Meaning Unit Indication Writing address Cooling water outlet 46101 Actual Valve X 10[ Temperature Cooling water inlet 46102 Actual Valve X 10[ Temperature Chilled water outlet 46103 Actual Valve X 10[ Temperature Chilled water inlet 46104...
  • Page 33: Power Panel

    n Power Panel Compressor Magnetic Contactors Main Terminal Block No Fuse Breaker Neutral Terminal Block Transformer Voltage Monitoring Relay Fuse Fig. 13 Rated electrical input power input and related electric control components are installed in power panel. Power input is structured in Terminal Block shape, Rated electrical input power which is approved to terminal block is approved to Magnet switch for compressor control.
  • Page 34: Machine On/Off Control

    n Machine On/Off Control There are hand mode and auto mode for powering ON/OFF the unit. 1. Hand mode- Hand mode is basic setting mode, and user can turn the unit ON and OFF by pushing Start/Stop button of HMI for 3 seconds. Select [user setting], [Hand/Auto mode] and [Hand control] to set this mode.
  • Page 35: Start Up

    START UP n Pre-start up Check the following and then operate the chiller. • Before operating the chiller, check the cold water, cooling water circulation pump, air handling equipment or other supplementary facility such as other equipment. Refer to the direction of the manufacturer. If the device is equipped with the components installed on site, install the equipment properly and accurately and check whether the wire is connected accurately.
  • Page 36: Operating Procedure

    • Check and audit all the fuses. All the fuses on the power and control panel must be installed in the correct location. • Check and audit the condition of the touch screen of PLC and HMI. HMI will display the LG logo as it is turned on and then the normal screen must be displayed afterwards.
  • Page 37: Operation Limit

    n Operation Limit Temperature The temperature limit condition during the operation of the chiller is as follows. ◆ Minimum cold water outlet temperature : 5℃ ◆ Maximum cold water outlet temperature : 15℃ ◆ Minimum coolant water inlet temperature : 24℃ ◆...
  • Page 38 Flow Rate Basic flow rate of the chiller follows the value indicated on the table showing the maximum, minimum and design flow rate. Higher or lower flow rate is permitted to achieve lower or high rise in temperature. To ensure appropriate heat exchange and turbulence Within the evaporator and condenser, the flow rate must exceed the minimum flow rate.
  • Page 39 Water flow rate (l/s) Cooling water pressure drop (English Unit) 1 compressor model 200 RT 1000 1200 1400 1600 1800 Water flow rate (gpm) Note: For flow out of this range, consult LG. - 39 - Operation & Maintenance Manual...
  • Page 40 1 compressor model 200 RT Water flow rate (l/s) Chilled water pressure drop (English Unit) 1 compressor model 200 RT 1000 1200 1400 1600 Water flow rate (gpm) Note: For flow out of this range, consult LG. Chiller Water-cooled Screw - 40 -...
  • Page 41: Operation

    OPERATION n Operation Sequence When the chiller starts the water pumps will start to operate at the same time. Also the SV1 will be turned on at minimum load location of the compressor. Also after the water pumps operates for 9 seconds, the chiller cold water and cooling water flow will be checked.
  • Page 42: Sensors

    n Sensors Negative Temperature Coefficient Negative Temperature Coefficient is used to check the cold water inlet temperature, cold water outlet tempera- ture, coolant water inlet temperature, coolant water outlet temperature and compressor discharge temperature. ◆ Cold water inlet temperature Sensor ◆...
  • Page 43: Service

    SERVICE n Cycle Part The structure of the cooling cycle of the water cooled chiller is shown below. (23) (24) (19) (19) (21) (20) (22) (10) (17) (16) (18) (20) (12) (11) (13) (14) (15) Fig. 16 PART PART PART PART Compressor Flux controller...
  • Page 44 Description Description Compressor case Bearing fixation ring Motor case Disk spring Oil separator Bearing lock nut Motor rotor assembly Water rotor Motor stator assembly Suction bearing Motor rotor washer Internal/External spacer ring of suction bearing Motor rotor spacer ring Oil induction ring Oil separator divider Suction filter Oil separator cartridge...
  • Page 45 (C) Discharge (B) Compression (A) Suction and seal Fig. 18 Screw compressor has the 3~4 gear control or no gear capacity control (Step-less) system installed. Capacity control system is composed of the slide valve, piston rod, cylinder, piston and piston ring. The slide valve and the piston are connected through the piston rod.
  • Page 46 Fig. 19 Solenoid valve (SV2) opened in no gear capacity control and closed solenoid valve (SV1) are installed on the inlet and outlet of the piston cylinder. Because the solenoid valve is controlled by the temperature controller of the freezer, the cooling capability control is controlled within 33%~100% (RC10~11) and 25%~100% (RC12~24).
  • Page 47 Stable ON : Solenoid valve energized T1, T3 : Pulse time 0.5 ~ 1.5 seconds OFF : Solenoid valve not energized T2, T4 : Pause time 10 ~ 20 seconds Fig. 20 Main function of the lubrication oil within the screw compressor is to lubricate, seal internally, cool and control the capacity.
  • Page 48 Compressors must be installed on the 2 sight glass by default and one is the sight glass for the top and the other for the bottom. Normal flux within the compressor oil tank must be maintained above the top range of the bottom sight glass and the middle level of the top sight glass when the compressor is operating.
  • Page 49 Symptom Cause Solution Wire open Check unconnected part Control fuse open Check grounded or shorted condition of control High pressure switch (HPS) stop circuit. Replace fuse Connection to terminal in loose Use navigator to initialize current alarm condition Check connection from CCP to contactor Incorrectly connected controller Check and reconnect wire Compressor is not...
  • Page 50 To protect the compressor, there are 2 PTC temperature Sensors installed inside the gas discharge side of the compressor and inside the motor coil. These Sensors are connected to INT69 control module to check the motor coil temperature and discharge gas temperature. When the temperature of one location of the areas that can be checked, exceeds the set response temperature of each PTC thermistor, the Sensor resistance increas- es and the INT69 control module is blocked from the motor contactor.
  • Page 51 Condenser Condenser uses the shell and tube type. Internal structure reduces the condensation temperature by 1~2°C compared to other products in 1.0 MPa design condition by improving the general condenser structure. Safety Device Flow Switch Flow switch is installed on the water outlet nozzle of all device as basic setting. The following figure shows the flux switch installed in general method.
  • Page 52 Dual Pressure Switch Dual pressure switch has the low pressure block switch and high pressure block switch equipped. The blocking pressure can be adjusted. Default setting is shown below. Low pressure block 3.2kgf/cm High pressure block 10.5kgf/cm Table 17 Low pressure switch and high pressure switch are closed in normal conditions and when the detected pressure exceeds the set value, it will open.
  • Page 53 Differential Pressure Switch Differential pressure switch is used for checking the lubrication problem. When the differential pressure between the condenser and evaporator is higher than the set value (4kgf/cm ), the switch will be closed. On the other hand, if the value is below the set value, the switch will be open. This switch will automatically be closed when the differential pressure is recovered to below set value.
  • Page 54 Anti-freezing Switch Anti-freezing switch is used for detecting very low temperature. In normal condition, the switch is closed and when the cold water outlet temperature is below 2°C, it will be open. When the temperature rises by 5°C or more, it will return to its normal condition. Anti-freezing switch is installed on the evaporator. Fig.
  • Page 55 Oil Filter Oil filter is installed on the oil separator on the pipe that returns the oil to the compressor. The differential pres- sure between the inlet and outlet of the oil filter must be checked periodically. Core valve to connect the inlet/outlet equipped with the pressure gauge on the oil separator must be installed.
  • Page 56 Oil Heater Oil heater prevents the lubrication condition from being reduced due to the low viscosity. The oil heater is also installed on the oil separator. 150 W oil heater is equipped with 220 V AC power input. Fig. 29 Solenoid Valve Solenoid value is installed on oil return pipe between oil filter and compressor by factory default.
  • Page 57: Control System

    n Control System Structure of power panel and control panel is shown below. Left power panel is composed of the electric parts related to Rated electrical input main power and the right control panel is composed of low voltage parts such as PLC and HMI device. Panel is designed to be water proof through the dual door system.
  • Page 58 Power Panel On the right side of the power panel, the terminal block for the main power connection is installed. This part is connected to the Rated electrical input main power cable for control power and to neutral line to the ter- minal block.
  • Page 59 At the bottom right of the power panel, the voltage monitoring relay is to check whether the power is appropriately installed. There are 3 fuses installed for the Rated electrical input power input to the voltage monitoring relay. The ventilation fan of the power panel controls the thermostat. When the internal temperature of the power panel is 35°...
  • Page 60 Voltage monitoring relay monitors 5 abnormal condition of the power. Abnormal conditions include over-voltage, under-voltage, reverse phase, phase loss and voltage unbalance. Of the abnormal conditions, reverse phase and voltage unbalance are selectively protected. The rest are mandatory. In case of an abnormal condition, the abnormal condition type and the abnormal value are shown on the normal display.
  • Page 61 Voltage unbalance trips when the unbalance exceeds more than 3 seconds in the range of +5%. In the same token, phase loss trip delays 2 seconds, and the reverse phase trip delays 0.5 seconds. Over-voltage trip location and trip delay can be configured through the rotator switch on the voltage monitoring relay.
  • Page 62 Control Panel On the external door of the control panel there is an emergency switch to immediately block the control output from PLC. You can press the emergency switch to instantly block the 220V AC power supplied from the PLC relay. You can turn the switch in clockwise direction to recover the output power.
  • Page 63 PLC on the control panel is installed on the central control station. PLC is assembled as HMI in the black box. PLC receives 24V DC power from the right SMPS (Switched mode power). Ventilation Fan Control Relay Control fuse SMPS (Switching Mode Thermostat Power Supply)
  • Page 64 Temperature Sensor Inside control Panel When operating the product, this is used for measuring the temperature inside the control panel. The shape and characteristics are as follows. Fig. 40 Ventilation Fan Ventilation fan has two sides attached; power panel and control panel. This fan sends air externally to respond to the temperature rise within both boxes when the product is operating, to prevent any problem when the temperature of each box rises.
  • Page 65: Maintenance

    n Maintenance Maintenance/Repair schedule Every 2 Every 3 Every 6 Every Every 2 Every 3 Every 6 Monthly Daily months months months 1 year years years years Checkpoint 10 h 500 h 1000 h 1500 h 2500 h 5000 h 10000 h 15000 h 30000 h...
  • Page 66: Trouble Shooting

    TROUBLE SHOOTING When the device is stopped more than once from the safety device, identify and correct the cause before restarting. General Malfunction Before resolving a special trouble shooting, this introduces the general troubles and troubleshooting methods. When the chiller is not operating at all, the power, refrigerant, configuration and alarm setting of the chiller must be checked.
  • Page 67 Symptom Potential cause Potential solution Chiller does not work. Chiller power check Check over-current protector Check whether fuse is not disconnected (If there is a fuse) Power recovery of chiller Insufficient refrigerant Check leakage and add refrigerant Incorrect or inaccurate Check device configuration chiller configuration Check alarm condition.
  • Page 68 Alarm Specific alarm identification method and potential cause of the issue are listed below. To cancel and recover the alarm, remove the cause and delete the alarm detail. Emergency alarm means that the operator pressed the emergency switch installed on the door of the control panel.
  • Page 69 The two causes of anti-freeze switch are as follows. Actually the alarm is recognized by the anti- freeze switch of low water temperature detected by the temperature sensor. For low water tempera- ture, the alarm setting temperature can be changed by the HMI. In case of any mechanically welded contactor problem of the magnetic contactor of the compressor, PLC cannot stop the compressor.
  • Page 70 Displayed alarm Recognition Potential cause Potential solution message • Charge additional refrigerant • Insufficient refrigerant • Necessary test/repair and • Refrigerant leakage charge additional refrigerant • Low pressure switch Pressure alarm • Low pressure switch trip • Increase low pressure setting is too high switch setting.
  • Page 71 Displayed alarm Recognition Potential cause Potential solution message • Charge refrigerant or • Compressor discharge • Insufficient refrigerant flux review valve condition Compressor discharge temperature is 90 °C or • Compressor error • Repair compressor • External temperature too temperature alarm above operate the •...
  • Page 72: Appendix

    Appendix ■ Wiring Diagram Fig. 42 Chiller Water-cooled Screw - 72 -...
  • Page 73: Cycle Diagram

    n Cycle Diagram Fig. 43 - 73 - Operation & Maintenance Manual...
  • Page 74: Check List

    n Check List 1. Project Information Content Information Project name Address Installing contractor Sales office Start-up performer 2. Model Information Content Information Model: Product Serial: Model: Compressor A Serial: Model: Compressor B Serial: Chiller Water-cooled Screw - 74 -...
  • Page 75 3. Prior Equipment Check Content Check Any damaged part? Comply with start-up? Bolts/Nuts tightened well? Does the power specification comply with the product specification? Is the cable correctly connected? Is the product correctly installed? Is the electric circuit protector correctly installed in accordance with the correct specification? Are all terminal blocks connected well? Are all plugs connected well?
  • Page 76 5. Start-up & Operation Contents Check Are all service valves of the refrigerant pipe open? (Discharge, suction, economizer, oil pipe etc.) Is there any leakage of refrigerant? (Compressor, condenser, economizer, evaporator etc.) Is the voltage of the terminal block within 10%? Is the voltage imbalance within 2%? Is there any abnormal noise or vibration? Does the alarm work normally?