Daikin DWSC - Vintage C User manual

Original Instructions
REV
01
Date
06/2021
Supersedes
D–EIMWC00803-21_00EN
Installation, Operation and Maintenance Manual
DWSC –Vintage C
Installation, Operation and Maintenance Manual
D–EIMWC00803-21_01EN

D–EIMWC00803-21_01EN - 2/57
CONTENTS
1INTRODUCTION .................................................................................................................................................. 10
1.1 Precautions against residual risks........................................................................................................................ 11
1.2 Description............................................................................................................................................................ 12
2RECEIVING THE UNIT ........................................................................................................................................ 13
3OPERATING LIMITS............................................................................................................................................ 14
3.1 Storing Storage..................................................................................................................................................... 14
3.2 Operation ..............................................................................................................................................................14
4MECHANICAL INSTALLATION .......................................................................................................................... 15
4.1 Safety.................................................................................................................................................................... 15
4.2 Positioning and assembly..................................................................................................................................... 15
4.3 System water volume ...........................................................................................................................................15
4.4 Condensation control with evaporative cooling tower .......................................................................................... 15
4.5 Condensation control with well water ...................................................................................................................16
4.6 Water piping..........................................................................................................................................................17
4.6.1 Water Pumps ........................................................................................................................................................17
4.6.2 Vessel Drains at Start-up......................................................................................................................................17
4.6.3 Evaporator and Condenser Water Piping............................................................................................................. 17
4.6.4 Important Note on Welding ...................................................................................................................................17
4.6.5 Flow Switch........................................................................................................................................................... 17
4.6.6 Cooling Towers.....................................................................................................................................................18
4.7 Water treatment .................................................................................................................................................... 18
4.8 Field Insulation Guide........................................................................................................................................... 19
4.9 PHYSICAL DATA AND WEIGHTS....................................................................................................................... 21
4.9.1 Evaporator ............................................................................................................................................................21
4.9.2 Condenser ............................................................................................................................................................21
4.9.3 Pumpdown............................................................................................................................................................21
4.9.4 Compressor ..........................................................................................................................................................22
4.10 Oil Coolers ....................................................................................................................................................... 22
4.11 Oil Heater .........................................................................................................................................................24
4.12 Relief Valves.................................................................................................................................................... 24
4.12.1 Refrigerant Vent Piping....................................................................................................................................24
5ELECTRICAL INSTALLATION............................................................................................................................ 25
5.1 General specifications .......................................................................................................................................... 25
5.2 Electrical supply....................................................................................................................................................25
5.3 Power wiring ......................................................................................................................................................... 25
5.4 Control power wiring .............................................................................................................................................26
5.5 Flow Switches.......................................................................................................................................................26
5.6 Control Panel Switches......................................................................................................................................... 26
5.7 Cable requirements .............................................................................................................................................. 26
5.8 Phase unbalance..................................................................................................................................................27
6PRESTART SYSTEM CHECKLIST..................................................................................................................... 28
7OPERATION......................................................................................................................................................... 29
7.1 Operator’s responsibilities ....................................................................................................................................29
7.2 Standby Power...................................................................................................................................................... 29
7.3 Lubrication System ............................................................................................................................................... 29
7.4 Hot Gas Bypass....................................................................................................................................................30
7.5 Condenser Water Temperature............................................................................................................................ 30
8MAINTENANCE ................................................................................................................................................... 31
8.1 Pressure/Temperature Chart................................................................................................................................ 31
8.2 Routine Maintenance............................................................................................................................................32
8.2.1 Lubrication ............................................................................................................................................................ 32
8.2.2 Changing Oil Filters ..............................................................................................................................................34
8.2.3 Refrigerant Cycle.................................................................................................................................................. 34
8.2.4 Electrical System .................................................................................................................................................. 34
8.2.5 Compressor Maintenance..................................................................................................................................... 35
8.2.6 Flanged joints disassembly................................................................................................................................... 35
8.2.7 Cleaning and Preserving ......................................................................................................................................36
8.3 Annual Shutdown.................................................................................................................................................. 36
8.4 Annual Startup ...................................................................................................................................................... 36
8.5 Repair of System ..................................................................................................................................................36
8.5.1 Pressure Relief Valve Replacement.....................................................................................................................36
8.5.2 Pumping Down......................................................................................................................................................36
8.5.3 Pressure Testing...................................................................................................................................................37
8.5.4 Leak Testing ......................................................................................................................................................... 37
8.5.5 Evacuation............................................................................................................................................................ 37
8.5.6 Charging the System ............................................................................................................................................ 37

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9MAINTENANCE SCHEDULE .............................................................................................................................. 38
10 SERVICE PROGRAMS AND WARRANTY STATEMENT.................................................................................. 40
11 PERIODIC CHECKS AND COMMISSIONING OF PRESSURE EQUIPMENT................................................... 40
12 DISPOSAL............................................................................................................................................................ 40
13 IMPORTANT INFORMATION REGARDING THE REFRIGERANT USED ........................................................ 41
13.1 Factory and Field charged units instructions ...................................................................................................41
14 ANNEX A: VARIABLE FREQUENCY DRIVE ..................................................................................................... 42
14.1 Acceptance of the Product...............................................................................................................................42
14.1.1 Checks ............................................................................................................................................................. 42
14.2 ABBREVIATIONS ............................................................................................................................................ 42
14.3 VFD Nomenclature For C Series .....................................................................................................................42
14.4 Vfds And Distortion ..........................................................................................................................................43
14.4.1 VFD Line Harmonics........................................................................................................................................43
14.4.2 Current Harmonics........................................................................................................................................... 43
14.4.3 Voltage Harmonics........................................................................................................................................... 43
14.4.4 EMI and RFI Filter............................................................................................................................................ 43
14.5 SAFETY ........................................................................................................................................................... 44
14.5.1 Avoid electrocution...........................................................................................................................................44
14.5.2 Residual risks...................................................................................................................................................45
14.6 HANDLING AND TRANSPORT....................................................................................................................... 45
14.7 MECHANICAL INSTALLATION....................................................................................................................... 46
14.7.1 Shipping ........................................................................................................................................................... 46
14.7.2 Cabinet Handling and Lifting............................................................................................................................46
14.7.3 Positioning and assembly ................................................................................................................................ 47
14.7.4 Minimum space requirements.......................................................................................................................... 47
14.8 GENERAL SPECIFICATIONS......................................................................................................................... 48
14.8.1 Product Identification........................................................................................................................................ 48
14.8.2 Individuation of Parts........................................................................................................................................49
14.8.3 Specification..................................................................................................................................................... 50
14.8.4 Directives and Standards.................................................................................................................................51
14.8.5 VFD terminals .................................................................................................................................................. 52
14.8.6 Piping Connections .......................................................................................................................................... 52
14.9 Maintenance..................................................................................................................................................... 53
14.9.1 Ordinary maintenance...................................................................................................................................... 53
14.9.2 Extraordinary maintenance.............................................................................................................................. 54
14.10 VFD COMMUNICATION..................................................................................................................................54
14.10.1 Modbus RTU Configuration .............................................................................................................................54
14.10.2 Modbus Parameters......................................................................................................................................... 55

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LIST OF FIGURES
Fig. 1 - Typical oil circuit........................................................................................................................................................ 6
Fig. 2 - Description of the labels applied to the electrical panel............................................................................................8
Fig. 3 - - Description of the labels applied to the Motor Terminal Box ..................................................................................8
Fig. 4 - Label on compressor................................................................................................................................................. 9
Fig. 5 - DWSC Major Component Locations.......................................................................................................................13
Fig. 6 - Condeser control scheme with cooling tower .........................................................................................................16
Fig. 7 - Condensation control scheme with well water........................................................................................................16
Fig. 8 - Flow switch mounting.............................................................................................................................................. 17
Fig. 9 - Oil Cooler Piping Across Chilled Water Pump........................................................................................................23
Fig. 10 - Oil Cooler Piping With City Water......................................................................................................................... 23
Fig. 11 - DWSC, Oil cooling connections............................................................................................................................23
Fig. 12 - Condenser 3-Way Valve....................................................................................................................................... 24
Fig. 13 - Label: Risk of Electric shock................................................................................................................................. 44
Fig. 14 - Angle to respect for lifting operation .....................................................................................................................46
Fig. 15 - Lifting the VFD ...................................................................................................................................................... 47
Fig. 16 - Minimum space requirements for VFD ................................................................................................................. 47
Fig. 17 - VFD Identification Label........................................................................................................................................ 48
Fig. 18 - Electrical Panel (mono) identification Label.......................................................................................................... 48
Fig. 19 - Electrical Panel (dual) identification Label ............................................................................................................48
Fig. 20 - Inverter panel parts (mono)................................................................................................................................... 49
Fig. 21 - Inverter panel parts (dual)..................................................................................................................................... 49
Fig. 22 - VFD replaceable parts highlighted........................................................................................................................ 50
Fig. 23 - P&ID diagram of the unit with inverter cooling line detail......................................................................................52
LIST OF TABLES
Table 1 - Flow switch rates.................................................................................................................................................. 18
Table 2 - Acceptable water quality limits............................................................................................................................. 18
Table 3 - Evaporator Data...................................................................................................................................................21
Table 4 - Condenser Data................................................................................................................................................... 21
Table 5 - Compressor Weights............................................................................................................................................ 22
Table 6 - DWSC, Oil cooler Data ........................................................................................................................................ 22
Table 7 - Cooling Water connection sizes........................................................................................................................... 23
Table 8 - Table 1 of EN60204-1 Point 5.2...........................................................................................................................26
Table 9 - Approved Polyolester oils for R134a units........................................................................................................... 29
Table 10 - Upper Limit For Wear Metals And Moisture In Polyolester Oils In Daikin Centrifugal Chillers..........................34

D–EIMWC00803-21_01EN - 5/57
Fig. 1 - Typical refrigerant circuit
Water inlet and outlet are indicative. Please refer to the machine dimensional diagrams for exact water connections

D–EIMWC00803-21_01EN - 6/57
Fig. 1 - Typical oil circuit

D–EIMWC00803-21_01EN - 7/57
LEGEND
ID
DESCRIPTION
1
CENTRIFUGAL COMPRESSOR
2
EVAPORATOR
3
CONDENSER
4
CHECK VALVE
5
SHUT-OFF VALVE*
6
SIGHT GLASS
7
ELECTRONIC EXPANSION VALVE
8
PLUGGED FITTING
9
SOLENOID VALVE
11
FILTER
12
DRYING FILTER #1
13
DRYING FILTER #2
14
MOTOR ACUATED VALVE
15
PRESSURE RELIEF VALVE Pset= 13,7 (10,5) bar
16
PRESSURE RELIEF VALVE Pset=13,7 bar
17
OIL HEAT EXCHANGER
18
OIL PUMP
19
WATER VALVE
20
VFD SOLENOID VALVE
21
PRESSURE RELIEF VALVE Pset= 13,7 bar
22
VFD FILTER
23
VFD HEAT EXCHANGER
24
4WAY VALVE (OIL CIRCUIT)
25
ACCESS FITTING
26
AIR VENT (WATER SIDE)
27
DRAIN (WATER SIDE)
28
BALL VALVE (WATER SIDE)
29
MANUAL ACTIVATED VALVE
30
Y FILTER (WATER SIDE)
PT
PRESSURE TRANSDUCER
PZH
HIGH PRESSURE SWITCH 22,7 Bar
TZAH
HIGH TEMPERATURE SWITCH (MOTOR THERMISTOR)
PSAL
LOW PRESSURE LIMITER (CONTROLLER FUNCTION)
TT
TEMPERATURE TRANSDUCER
DPS
DIFFERENTIAL PRESSURE SWITCH (* N° 2 for VFD units)
FS
FLOW SWITCH
L1
SUCTION LINE (Evaporator->Compressor)
L2
DISCHARGE LINE (Compressor->Condenser)
L3
MAIN LIQUID LINE (Condenser->Evaporator)
L4
MOTOR COOLING LINE #1 (Cond->Filter)
L5
MOTOR COOLING LINE #2 (Filter)
L6
MOTOR COOLING LINE #3 (Filter->Checkvalve)
L7
MOTOR COOLING LINE #4 (Check valve->Motor)
L8
LIQUID INJECTION #1 (Condenser->Solenoid valve)
L9
LIQUID INJECTION #2 (Solenoidvalve->Compressor)
L10
MOTOR COOLING LINE #5 (Motor->Evaporator)
L11
THD/VFD COOLING LINE (*n° 2 lines L11 for doubleVFD)
L12
OIL FEED LINE #1 (Oil Cooler->Compressor)
L13
OIL FEED LINE #2
L14
OIL FEED LINE #3
L15
DRAIN LINE (Compressor->Oil Tank)
L16
VENT LINE (Compressor->Oil Tank)
L17
OIL EQUALIZER LINE (Compressor->Oil Tank)
L18
THURST PUMP LINE (Compressor->Checkvalve)
L19
WATER LINE OUT
L20
WATER LINE IN
L21
HOT GAS BYPASS LINE
L22
OIL LINE
All the shut off valves (ID 5) are only service valves and they shall not be closed except for
maintenance operations.

D–EIMWC00803-21_01EN - 8/57
Fig. 2 - Description of the labels applied to the electrical panel
1) Electrical hazard symbol
4) Control panel code
2) Non flammable gas symbol
5) Unit nameplate data
3) Gas type
6) Unit characteristics technical
Fig. 3 - - Description of the labels applied to the Motor Terminal Box
1) Terminal box fixing
3) Electrical hazard symbol
2) Manufacturer’s logo
4) Terminal connection

D–EIMWC00803-21_01EN - 9/57
Fig. 4 - Label on compressor
DEVICE UNDER PRESSURE
RELEASE PRESSURE IN
ALL COMPRESSOR
SECTIONS BEFORE
SERVICING
For more detail see par.13.2.5

D–EIMWC00803-21_01EN - 10/57
1 INTRODUCTION
This manual is an important supporting document for qualified personnel but it is not intended to replace such
personnel.
The units described in the present manual represent a valuable investment. Maximum care should
be taken to ensure correct installation and appropriate working conditions of the units.
THIS MANUAL, WIRING DIAGRAMS AND DIMENSIONAL DRAWINGS MUST BE CONSIDERED
ESSENTIALS, KEEP A COPY OF THESE DOCUMENTS ALWAYS AVAILABLE INSIDE THE UNIT.
Installation and maintenance must be performed by qualified and specifically trained personnel
only.
Correct maintenance of the unit is indispensable for its safety and reliability. Manufacturer’s service
centres are the only having adequate technical skill for maintenance.
READ THIS DOCUMENT IN ITS ENTIRETY BEFORE BEGINNING ANY WORK ON THE UNIT.
ALL FEDERAL, STATE, LOCAL ENVIRONMENTAL AND SAFETY REGULATIONS INCLUDING DAIKIN
SAFETY RULES MUST BE FOLLOWED.
All appropriate Personal Protective Equipment (“PPE”) must be used, and a Job Hazard Analysis
(“JHA”) must be completed, before beginning any work on the unit.
Technicians performing this work must be properly trained on Daikin DWSC Centrifugal equipment.
Important Note: In case of any procedure requires accessing the refrigerant circuit of these units,
remember that refrigerant is under pressure and oils are contained in these circuits.
Ensure that all appropriate pump-down or pump-out service valves are in the correct position, open
or closed as required and holding.
Solenoid valves and expansion valves can trap refrigerant and oils, these devices must be operated
manually to release any trapped gases and oils while in pump-down or pump-out operation.
All refrigerant lines and components of the unit must be evacuated to at least 30 kPa vacuum and
verified before opening any charging valves, venting schrader valves or testing ports.
These devices must be open and vented while accessing the refrigerant system. In some cases,
cross connection lines may be required to ensure recovery of all refrigerant in all sections of the
affected system or components.
All units are delivered from factory as complete sets which include wiring diagrams and
dimensional drawings with size, weight and features of each model.
In case of any discrepancy between this manual and the two aforesaid documents, please refer to
the wiring diagram and dimensional drawings.
Power Wiring
•Qualified and licensed electricians must perform wiring. Shock hazard exists.
•Connections to terminals must be made with copper lugs and copper wire.
•Before any installation and connection work, the system must be switched off and
secured. After switching off the unit, when an inverter is installed, the intermediate
circuit capacitors of the inverter are still charged with high voltage for 5 minutes.
•Before taking any action, switch off the main switch to cut off electricity to the
machine.
When the machine is off but the disconnecting switch is in the closed position, unused circuits are
always live.
Never open the terminal board box of the compressors unless the main switch of the machine has
been switched off.
•The units of the series can be provided with non-linear high power electrical
components (inverters) which introduce higher harmonics, can cause considerable
leakage to earth, (higher than 300 mA). The electricity supply system protection must
take the above values into account.
Before starting the installation of the unit, please read this manual carefully. Starting up the unit is
absolutely forbidden if all instructions contained in this manual are not clear.
Commissioning of the unit (first start up) must be performed by Daikin representative.
It is absolutely forbidden to remove all the protections of the moving parts of the unit.
If the unit mounts suction and discharge valves they need to be secured in open position when the
unit is installed, by means of a lead seal or equivalent. This to avoid they are put in closed position.
The use of this valve is intended for compressor maintenance.

D–EIMWC00803-21_01EN - 11/57
If refrigerant charge of the unit is more than 500 kg it is necessary to install gas sensor on water
circuit to catch an eventual gas leakage.
Verify that the unit has not zero pressure in the refrigerant circuit before charging water into the
heat exchangers. In case there is not pressure in the refrigerant circuit, do not charge water.
Do not use oxygen or a mixture of refrigerant and air to build up pressure as explosion can occur
causing serious personal injury.
1.1 Precautions against residual risks
1. Install the unit according to the instructions set out in this manual.
2. Regularly carry out all the maintenance operations foreseen in this manual.
3. Wear protective equipment (gloves, eye protection, hard hat, etc.) suited to the work in hand; do not wear clothes
or accessories that can get caught or sucked in by flows of air; tie back long hair before entering the unit.
4. Before opening the machine panelling make sure that it is firmly hinged to the machine.
5. The fins on heat exchangers and the edges of metal components and panels can cause cuts.
6. Do not remove the guards from mobile components while the unit is operating.
7. Make sure that mobile component guards are fitted correctly before restarting the unit.
8. Fans, motorsand belts drives might be running: before entering, always waitfortheseto stop andtake appropriate
measures to prevent them from starting up.
9. The surfaces of the machine and pipes can get very hot or cold and cause the risk of scalding.
10. Never exceed the maximum pressure limit (PS) of the water circuit of the unit.
11. Before removing parts on the pressurised water circuits, close the section of the piping concerned and drain the
fluid gradually to stabilise the pressure at the atmospheric level.
12. Do not use your hands to check possible refrigerant leaks.
13. Disable the unit from the mains using the main switch before opening the control panel.
14. Check that the unit has been grounded correctly before starting it.
15. Install the machine in a suitable area; in particular, do not install it outdoors if it is intended for use indoors.
16. Do not use cables with inadequate sections nor extension cord connections, even for very short periods or
emergencies.
17. For units with power correction capacitors, wait 5 minutes after removing the electric power supply before
accessing the inside of the switch board.
18. If the unit is equipped with compressors with integrated inverter, disconnect it from the mains and wait a minimum
of 20 minutes before accessing it to carry out maintenance: residual energy in the components, which takes at
least this length of time to dissipate, poses the risk of electrocution.
19. The unit contains pressurised refrigerant gas: the pressurised equipment must not be touched except during
maintenance, which must be entrusted to qualified and authorised personnel.
20. Connect up the utilities to the unit following the indications set out in this manual and on the panelling of the unit
itself.
21. In order to avoid an environmental risk, make sure that any leaking fluid is collected in suitable devices in
accordance with local regulations.
22. If a part needs to be dismantled, make sure it is correctly re-assembled before starting the unit.
23. When the rules in force require the installation of fire-fighting systems near the machine, check that these are
suitable for extinguishing fires on electrical equipment and on the lubricating oil of the compressor and the
refrigerant, as specified on the safety data sheets of these fluids.
24. When the unit is equipped with devices for venting overpressure (safety valves): when these valves are triggered,
the refrigerant gas is released at a high temperature and speed; prevent the release of gas from harming people
or objects and, if necessary, discharge the gas according to the provisions of EN 378-3 and the local regulations
in force.
25. Keep all the safety devices in good working order and check them periodically according to the regulations in
force.
26. Keep all lubricants in suitably marked containers.
27. Do not store inflammable liquids near the unit.
28. Solder or braze only empty pipes after removing all traces of lubricant oil; do not use flames or other heat sources
in the vicinity of pipes containing refrigerant fluid.
29. Do not use naked flames near the unit.
30. The machinery must be installed in structures protected against atmospheric discharge according to the
applicable laws and technical standards.
31. Do not bend or hit pipes containing pressurised fluids.
32. It is not permitted to walk or rest other objects on the machines.
33. The user is responsible for overall evaluation of the risk of fire in the place of installation (for example, calculation
of the fire load).
34. During transport, always secure the unit to the bed of the vehicle to prevent it from moving about and overturning.
35. The machine must be transported according to the regulations in force taking into account the characteristics of
the fluids in the machine and the description of these on the safety data sheet.
36. Inappropriate transport can cause damage to the machine and even leaking of the refrigerant fluid. Before start-
up, the machine must be checked for leaks and repaired accordingly.

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37. The accidental discharge of refrigerant in a closed area can cause a lack of oxygen and, therefore, the risk of
asphyxiation: install the machinery in a well ventilated environment according to EN 378-3 and the local
regulations in force.
38. The installation must comply with the requirements of EN 378-3 and the local regulations in force; in the case of
installations indoors, good ventilation must be guaranteed and refrigerant detectors must be fitted when
necessary.
1.2 Description
Daikin Centrifugal Water Chillers are complete, self-contained, automatically controlled fluid chilling units. Each unit is
completely assembled and factory tested before shipment. Models DWSC are cooling-only.
In the DWSC, each unit has one compressor connected to a condenser and evaporator. Information in this manual referring
to all DWSC units except where specifically noted.
The chillers use refrigerant R-134a, R-513A and R-1234ze to reduce the size and weight of the package compared to
negative pressure refrigerants, and since these refrigerants operates at a positive pressureover the entire operation range,
no purge system is required.
The controls are pre-wired, adjusted and tested. Only normal field connections such as piping, electrical and interlocks,
etc. are required, thereby simplifying installation and increasing reliability. Most necessary equipment protection and
operating controls are factory installed in the control panel.
The basic sizes of units are the 079, 087, 100, 113 and 126. They provide a cooling capacity range from 750 kW to
4500 kW.

D–EIMWC00803-21_01EN - 13/57
2 RECEIVING THE UNIT
The unit should be inspected immediately after receipt for possible damage.
All Daikin centrifugal water chillers are shipped FOB factory and all claims for handling and shipping damage are the
responsibility of the consignee.
Insulation corners from the evaporator’s rigging hole locations are shipped loose and should be glued in place after the
unit is finally placed. Neoprene vibration pads are also shipped loose. Check that these items have been delivered with
the unit.
If so equipped, leave the shipping skid in place until the unit is in its final position. This will aid in handling the equipment.
Extreme care must be used when rigging the equipment to prevent damage to the control panels or refrigerant piping. See
the certified dimension drawings included in the job submittal for the center of gravity of the unit. Consult the local Daikin
sales office for assistance if the drawings are not available.
The unit can be lifted by fastening the rigging hooks to the four corners of the unit where the rigging eyes are located (see
Figure below). Spreader bars must be used between the rigging lines to prevent damage to the control panels, piping and
motor terminal boxes. Fig. 5 - DWSC Major Component Locations
Chilled water and condenser connection location can vary. Check markings on unit or consult unit
certified drawings for connection locations on specific units
VFD panel + Unit
control panel +
Auxliaries
Operator
interface panel
Rigging
locations (6)
available
Rigging
locations (6)
available
Evaporator
Condenser

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3 OPERATING LIMITS
3.1 Storing Storage
Environmental conditions must be within the following limits:
Equipment room temperature, standby
•Water in vessels and oil cooler: 32F to 122F (0C to 50C)
•Without water in vessels and oil cooler: 0F to 122F (-18C to 50C)
•WSC without water in vessels: 0F to 122F (-18C to 50C)
Storing below the minimum temperature may cause damage to components. Storing above the maximum temperature
causes opening of safety valves. Storing in condensing atmosphere may damage electronic components.
3.2 Operation
Operation is allowed within the following limits:
•Equipment room temperature, operating: 32F to 104F (0C to 40C)
•Maximum entering condenser water temperature, startup: design plus 5 °F (2.7°C)
•Maximum entering condenser water temperature, operating: job specific design temperature
•Minimum entering condenser water temperature, operating: see page 30.
•Minimum leaving chilled water temperature: 38F (3.3C)
•Minimum leaving chilled fluid temperature with correct anti-freeze fluid: 15F (-9.4C)
•Maximum entering chilled water temperature, operating: 90F (32.2C)
•Maximum oil cooler/VFD entering temperature: 90F (32.2C)
•Minimum oil cooler/VFD entering temperature: 42F (5.6C)

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4 MECHANICAL INSTALLATION
4.1 Safety
The machine must be firmly secured to the ground.
It is essential to observe the following instructions:
- The machine must be raised only by the lifting points. Only these points can support the whole weight of the unit.
- Do not allow unauthorised and/or unqualified personnel to access the machine.
- It is forbidden to access the electrical components without having opened the machine’s general disconnecting switch
and switched off the power supply.
- It is forbidden to access the electrical components without using an insulating platform. Do not access the electrical
components if water and/or moisture are present.
- All operations on the refrigerant circuit and on components under pressure must be carried out by qualified personnel
only.
- Replacement of a compressor or addition of lubricating oil must be carried out by qualified personnel only- Sharp edges
can cause wounds. Avoid direct contact.
- Avoid introducing solid bodies into the water pipes while the machine is connected to the system.
- A mechanical filter must be installed on the water pipe connected to the heat exchanger inlet.
- Themachineis supplied withsafety valves, that are installedon both the high and the low pressure sides ofthe refrigerant
circuit.
If the unit mounts suction and discharge valves they need to be secured in open position when the
unit is installed, by means of a lead seal or equivalent. This to avoid they are put in closed position.
The use of this valve is intended for compressor maintenance.
4.2 Positioning and assembly
The unit must be mounted on a level concrete or steel base and must be located to provide service clearance at one end
of the unit for possible removal of evaporator tubes and/or condenser tubes. Evaporator and condenser tubes are rolled
into the tube sheets to permit replacement if necessary. The length of the vessel should be allowed at one end. Doors or
removable wall sections can be utilized for tube clearance.
Minimum clearance at all other points, including the top, is 3 feet (1 meter).
The shipped-loose neoprene vibration pads should be located under the corners of the unit (unless the job specifications
state otherwise). They are installed to be flush with the sides and outside edge of the feet. Most DWSC units have six
mounting feet although only the outer four are required. Six pads are shipped and the installer can place pads under the
middle feet if desired.
Make sure that the floor or structural support is adequate to support the full operating weight of the complete unit.
It is not necessary to bolt the unit to the mounting slab or framework; but should this be desirable, 1 1/8”(28.5 mm)
mounting holes are provided in the unit support at the four corners.
4.3 System water volume
All chilled water systems need adequate time to recognize a load change, respond to that load change and stabilize,
without undesirable short cycling of the compressors or loss of control. In air conditioning systems, the potential for short
cycling usually exists when the building load falls below the minimum chiller plant capacity or on close-coupled systems
with very small water volumes.
Some of the things the designer should consider when looking at water volume are the minimum cooling load, the minimum
chiller plant capacity during the low load period and the desired cycle time for the compressors.
Assuming that there are no sudden load changes and that the chiller plant has reasonable turndown, a rule of thumb of
“gallons of water volume equal to two to three times the chilled water gpm flow rate”is often used.
A properly designed storage tank should be added if the system components do not provide sufficient water volume.
4.4 Condensation control with evaporative cooling tower
The minimum condenser inlet water temperature should not be less than 20 °C at full water tower flow rate.
If the water temperature must be lower, even the water flow must be reduced proportionately.
To modulate the water flow to the condenser, install a three-way by-pass valve. The figure shows how the three-way valve
is applied to cool the condenser. The three-way valve can be activated by a pressure actuator which guarantees proper
condensing pressure in the case where the water temperature entering the condenser is less than 20 °C.
A three-way servo-controlled valve or inverter driven circulation pump could be used instead of a valve with pressure
actuator. Both of these devices could be controlled by a 0-10 Vdc analogue signal emitted by the machine electronic
controller according to the condenser inlet water temperature.

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Fig. 6 - Condeser control scheme with cooling tower
1
Cooling tower
2
Condenser
4.5 Condensation control with well water
If ground water is used to cool the condenser, install a normally regulating control valve, direct drive, at condenser outlet.
This regulating valve must ensure an adequate condensing pressure in the case where the water temperature entering the
condenser is less than 20 °C.
A service valve with pressure outlet is provided on the condenser shell for this purpose.
The valve must modulate its opening according to condensing pressure. When the machine shuts down, the valve will
close preventing the condenser from emptying.
Fig. 7 - Condensation control scheme with well water
1
From the main condenser pump
2
Service valve
3
Direct acting water regulating valve
4
Configuration required when the regulating valve is not used
5
At Drain

D–EIMWC00803-21_01EN - 17/57
4.6 Water piping
If the charge of the unit is more than 500 kg it is necessary to install gas sensor on water circuit to
catch an eventual gas leakage (EN 378).
4.6.1 Water Pumps
Avoid the use of 3600/3000-rpm (two-pole motor) pump motors. It is not uncommon to find that these pumps operate with
objectionable noise and vibration.
It is also possible to build up a frequency beat due to the slight difference in the operating rpm of the pump motor and the
Daikin centrifugal motor. Daikin encourages the use of 1750/1460 rpm (four-pole) pump motors.
4.6.2 Vessel Drains at Start-up
Unit vessels are drained of water in the factory and are shipped with the drain plugs in the heads removed and stored in
the control panel or with open ball valves in the drain hole. Be sure to replace plugs or close the valves prior to filling the
vessel with fluid.
4.6.3 Evaporator and Condenser Water Piping
All evaporators and condensers come standard with Victaulic AWWA C-606 groove nozzles (also suitable for welding), or
optional flange connections. The installing contractor must provide matching mechanical connections or transitions of the
size and type required.
4.6.4 Important Note on Welding
If welding is to be performed on the mechanical or flange connections, remove the solid-state temperature sensor and
thermostat bulbs from the wells to prevent damage to those components. Also properly ground the unit or severe damage
to the MicroTech unit controller can occur.
Water pressure gauge connection taps and gauges must be provided in the field piping at the inlet and outlet connections
of both vessels for measuring the water pressure drops. The pressure drops and flow rates for the various evaporators
and condensers are job specific and the original job documentation can be consulted for this information. Refer to the
nameplate on the vessel shell for identification.
Be sure that water inlet and outlet connections match certified drawings and stenciled nozzle markings. The condenser is
connected with the coolest water entering at the bottom to maximize subcooling.
Note: When common piping is used for both heating and cooling modes, care must be taken to provide that water flowing
through the evaporator cannot exceed 110°F which can cause the relief valve to discharge refrigerant or damage controls.
Thepiping mustbe supportedto eliminate weight and strain on the fittings andconnections. Piping mustalso be adequately
insulated. A cleanable 20-mesh water strainer must be installed in both water inlet lines. Sufficient shutoff valves must be
installed to permit draining the water from the evaporator or condenser without draining the complete system.
4.6.5 Flow Switch
A water flow switch must be installed to signal the presence of adequate water flow to the vessels before the unit can start.
They also serve to shut down the unit in the event that water flow is interrupted to guard against evaporator freeze-up or
excessive discharge pressure.
Thermal dispersion flow switches and differential pressure switches are available from Daikin as a factory-mounted option.
It is mounted in an evaporator and condenser water nozzle and factory wired.
A paddle type flow switch can be supplied by the owner for field mounting and wiring.
Fig. 8 - Flow switch mounting
If flow switches, by themselves, are being used, electrical connections in the Unit Electrical Panel must be made following
the wiring diagram.
Flow direction marked on switch
1”NPT flow switch connection
Tee

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Table 1 - Flow switch rates
Pipe Size
(NOTE!)
inch
1 1/4
1 1/2
2
2 1/2
3
4
5
6
8
mm
32 (2)
38 (2)
51
63 (3)
76
102 (4)
127 (4)
153 (4)
204 (5)
Min.
Adjst.
Flow
gpm
5.8
7.5
13.7
18.0
27.5
65.0
125.0
190.0
205.0
Lpm
1.3
1.7
3.1
4.1
6.2
14.8
28.4
43.2
46.6
No
Flow
gpm
3.7
5.0
9.5
12.5
19.0
50.0
101.0
158.0
170.0
Lpm
0.8
1.1
2.2
2.8
4.3
11.4
22.9
35.9
38.6
Max.
Adjst.
Flow
gpm
13.3
19.2
29.0
34.5
53.0
128.0
245.0
375.0
415.0
Lpm
3.0
4.4
6.6
7.8
12.0
29.1
55.6
85.2
94.3
No
Flow
gpm
12.5
18.0
27.0
32.0
50.0
122.0
235.0
360.0
400.0
Lpm
2.8
4.1
6.1
7.3
11.4
27.7
53.4
81.8
90.8
NOTES:
1. A segmented 3-inch paddle (1, 2, and 3 inches) is furnished mounted, plus a 6-inch paddle loose.
2. Flow rates for a 2-inch paddle trimmed to fit the pipe.
3. Flow rates for a 3-inch paddle trimmed to fit the pipe.
4. Flow rates for a 3-inch paddle.
5. Flow rates for a 6-inch paddle.
6. There is no data for pipe sizes above 8-inch. A switch minimum setting should provide protection against no flow and
close well before design flow is reached.
Alternatively, for a higher margin of protection, normally open auxiliary contacts in the pump starters can be wired in series
with the flow switches.
Freeze Notice: Neither the evaporator nor the condenser is self-draining; both must be blown out to
help avoid damage from freezing.
The piping should also include thermometers at the inlet and outlet connections and air vents at the high points.
The water heads can be interchanged (end for end) so that the water connections can be made at either end of the unit. If
this is done, new head gaskets must be used and control sensors relocated.
In cases where the water pump noise can be objectionable, vibration isolation sections are recommended at both the inlet
and outlet of the pump. In most cases, it will not be necessary to provide vibration eliminator sections in the condenser
inlet and outlet water lines. But they can be required where noise and vibration are critical.
4.6.6 Cooling Towers
The condenser water flow rate must be checked to be sure that it conforms to the system design. If tower fan control is not
adequate, a tower bypass valve is recommended. Unless the system and chiller unit are specifically for condenser bypass
or variable condenser flow is not recommended since low condenser flow rates can cause unstable operation and
excessive tube fouling. Tower water treatment is essential for continued efficient and reliable unit operation. If not available
in-house, competent water treatment specialists can be contracted.
4.7 Water treatment
Table 2 - Acceptable water quality limits
DAE Water quality requirements
Shell&tube
Flooded
BPHE
Ph (25 °C)
6.8 ÷ 8.4
7.5 –9.0
Electrical conductivity [μS/cm] (25 °C)
< 800
< 500
Chloride ion [mg Cl- / l]
< 150
< 300
Sulphate ion [mg SO42- / l]
< 100
< 100
Alkalinity [mg CaCO3 / l]
< 100
< 200
Total Hardness [mg CaCO3 / l]
< 200
75 ÷ 150
Iron [mg Fe / l]
< 1
< 0.2
Ammonium ion [mg NH4+ / l]
< 1
< 0.5
Silica [mg SiO2 / l]
< 50
NO
Chlorine molecular (mg Cl2/l)
< 5
< 0.5

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4.8 Field Insulation Guide

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Compressor feet