Daikin Packaged Water-Cooled Heat Pumps

Introduction

The Daikin EWWQ-KC packaged water-cooled water chillers are designed for indoor installation and are used for cooling and/or heating applications. These units are available in 7 standard sizes with nominal cooling capacities ranging from 14 to 64 kW. The EWWQ units can be combined with Daikin fan coil units or air handling units for air conditioning purposes. They can also be used for supplying chilled water for process cooling.

This manual describes the procedures for unpacking, installing, and connecting the EWWQ units. It is intended for use by expert or trained users in shops, light industry, farms, or for commercial use by lay persons.

Sound pressure level is less than 70 dB(A).

Options and Features

Options

• BMS-connection optional connectivity kit card (MODBUS TCP/IP, BACNET MSTP, BACNET TCP/IP)
• Remote user interface
• Low noise operation kit (field installed)
• Entering water temperature kit
• Master/slave water temperature kit
• Modem for Daikin On Site

Standard Features

• Glycol application for chilled water temperature down to –10°C.
• Powered Contact
• General alarm
• Voltage free digital contacts (general operation, Reversing Valve, Evaporator Water pump, Condenser Water pump, Backup heater)
• Changeable remote inputs (remote start/stop, remote cooling/heating, dual setpoint, External Alarm, Setpoint reset)

Operation Range

The operating limits for EWWQ014-033 and EWWQ049-064 models are illustrated in the figures below. These figures show the Evaporator Leaving Water Temperature (ELWT) and Condenser Leaving Water Temperature (CLWT).

Figure 1: Operating limits on EWWQ014-033

This graph displays the operational range for EWWQ014-033 models, indicating zones for operation with water and with glycol.

Figure 2: Operating limits EWWQ049-064

This graph displays the operational range for EWWQ049-064 models, indicating zones for operation with water and with glycol.

Key:

• ELWT: Evaporator leaving water temperature
• CLWT: Condenser leaving water temperature
• 1: Operation with water
• 2: Operation with glycol (below ELWT=4°C)

Main Components

The main components of the unit include:

• Compressor
• Evaporator
• Condenser
• Switchbox
• Chilled water in/out
• Condenser water in/out
• Evaporator entering/leaving water temperature sensors
• Condenser entering/leaving water temperature sensors
• Digital Controller and display
• Power supply intake
• Ball valve (optional)
• Water filter (optional)
• Air purge valve (optional)
• Flow-switch (optional)
• Main switch

Selection of Location

Units are designed for indoor installation and require a location that meets the following criteria:

• Sufficiently strong foundation to support the unit's weight and a flat floor to prevent vibration and noise.
• Adequate space around the unit for servicing.
• No danger of fire due to leakage of non-flammable gas.
• Location should minimize disturbance from unit noise.
• Ensure that water cannot cause damage in case of drips.
• The equipment is not intended for use in potentially explosive atmospheres.

Inspecting and Handling the Unit

Upon delivery, the unit should be checked for any damage, which should be reported to the carrier immediately.

Unpacking and Placing the Unit

1. Cut straps and remove the cardboard box from the unit.
2. Cut straps and remove the cardboard box with water piping from the pallet.
3. Remove the four screws fixing the unit to the pallet.
4. Level the unit in both directions.
5. Use four anchor bolts with M8 thread to fix the unit in concrete (directly or using floor standing supports).
6. Remove the service front plate.

Important Information Regarding the Refrigerant Used

This product contains fluorinated greenhouse gases (R410A) covered by the Kyoto Protocol. Do not vent gases into the atmosphere. The Global Warming Potential (GWP) value is 2090. The refrigerant quantity is indicated on the unit's name plate.

Checking the Water Circuit

The units are equipped with water inlets and outlets for connection to chilled and hot water circuits. These must be provided by a licensed technician and comply with all relevant regulations.

WARNING: The unit is only to be used in a closed water system. Application in an open water circuit can lead to excessive corrosion of the water piping.

Before installation, check the following points:

Additional components not delivered with the unit

1. A circulation pump must discharge water directly into the heat exchanger.
2. Drain taps must be provided at all low points for complete drainage during maintenance or shutdown.
3. Anti-vibration systems in water piping are recommended to avoid straining and transmitting vibration and noise.

Additional water piping delivered with the unit

All additional water piping must be installed according to the piping diagram. The flowswitch must be connected as described on the wiring diagram. See also chapter "Before starting".

Plastic bag 1 (water piping evaporator) includes: 2x Ball valve, 1x Water filter, 1x Air purge, 1x T-joint for air purge, 2x Flowswitch pipe, 1x Flowswitch + 1x T-joint.

Plastic bag 2 (water piping condenser) includes: 2x Ball valve, 1x Water filter, 1x Air purge, 1x T-joint for air purge.

The flowswitch must be installed in the water outlet pipe of the evaporator to prevent operation at too low a water flow.

WARNING: It is crucial to install the flowswitch correctly in relation to the water flow direction to ensure proper protection against freezing.

A specific terminal is provided in the switch box for the electrical connection of the flowswitch. Refer to the wiring diagram.

Shut-off valves must be installed at the unit for normal servicing of the water filter without draining the complete system.

Air purge valves must be provided at all high points of the system for easy servicing.

The water filter must be installed in front of the unit to remove dirt and prevent damage to the unit or evaporator/condenser. The water filter must be cleaned regularly.

Table 3: Water quality specifications

Connecting the Water Circuit

Evaporator and condenser have GAS male pipe threads for water inlet and outlet. Connections must be made respecting the water in- and outlet as shown in the outlook diagram.

Avoid air, moisture, or dust in the water circuit. Always consider the following when connecting:

1. Use clean pipes only.
2. Hold the pipe end downwards when removing burrs.
3. Cover the pipe end when inserting through a wall to prevent dust and dirt entry.

WARNING: Use a good thread sealant for connections. The sealant must withstand system pressures and temperatures and be resistant to glycol. External surfaces of water pipes must be protected against corrosion.

Water Charge, Flow and Quality

A minimum water volume and flow rate are required for proper operation. Refer to the table below for water flow operation ranges.

Table 4: Water flow operation range

WARNING: The water pressure should not exceed the maximum working pressure of 10 bar.

WARNING: Provide adequate safeguards in the water circuit to ensure water pressure does not exceed the maximum allowable working pressure.

Piping Insulation

The complete water circuit, including all piping, must be insulated to prevent condensation and reduce cooling capacity loss.

11.1 Antifreeze protection for BPHE and recovery exchangers

If heat exchangers are completely empty and cleaned with antifreeze solution, additional methods can be used against freezing.

Consider the following protection methods:

1. Continuous water flow circulation inside piping and exchangers.
2. Addition of an appropriate amount of glycol to the water circuit, or alternative, additional heat insulation and heating of exposed piping.
3. If the unit is not used during winter, empty and clean the heat exchanger.

The installer or local maintenance personnel are responsible for ensuring that antifreeze methods are used. Failure to follow these instructions may result in unit damage. Damage caused by freezing is excluded from the warranty.

Field Wiring

WARNING: All field wiring and components must be installed by a licensed electrician and comply with relevant European and national regulations.

Field wiring must be carried out according to the wiring diagram supplied with the unit and the instructions below. Use a dedicated power circuit; never use a power supply shared by another appliance.

WARNING: During the removal of the control cabinet door, disconnect the display cable before removing the panel completely.

12.1 Power circuit and cable requirements

1. The electrical power supply to the unit must be switchable on/off independently of other plant equipment.
2. A dedicated power circuit with safety devices (circuit breaker, slow blow fuse on each phase, earth leak detector) must be provided. Recommended fuses are mentioned on the wiring diagram.

WARNING: Switch off the main isolator switch before making any connections.

12.2 Connection of the water-cooled water chiller power supply

1. Install cable gland to proper tight main power supply cable.
2. Using the appropriate cable, connect the power circuit to the N, L1, L2 and L3 terminals of the unit (cable section 2.5~16mm²).
3. Connect the earth conductor (yellow/green) to the earthing terminal PE.

12.3 Point for attention regarding quality of the public electric power supply

This equipment complies with EN/IEC 61000-3-11 provided that the system impedance Zsys is less than or equal to Zmax at the interface point between the user's supply and the public system. The installer or user must ensure, by consultation with the distribution network operator, that the equipment is connected only to a supply with a system impedance Zsys less than or equal to Zmax.

Table 5: Impedance Z

Only for EWWQ014~064: Equipment complying with EN/IEC 61000-3-12.

12.4 Interconnection cables

• Voltage free contact: The PCB is provided with voltage free contacts to indicate the status of the unit. These can be wired as described on the wiring diagram.
• Remote inputs: Possibilities exist to install remote inputs, which can be installed as shown on the wiring diagram.

Operator's Responsibilities

The operator must be appropriately trained and familiar with the system before operating the unit. This includes studying the microprocessor operating manual and wiring diagram to understand start-up, operation, shutdown sequences, and safety devices.

A technician authorized by the manufacturer is available during the initial start-up phase to answer questions and provide instructions.

The operator must keep a record of operating data and maintenance activities for each installed unit.

If abnormal operating conditions are noted, consult the authorized technical service.

WARNING: If the unit is switched off, the compressor oil heater cannot be used. Once reconnected to the mains, allow the compressor oil heater to charge for at least 6 hours before restarting the unit. Failure to do so may cause compressor damage due to liquid accumulation.

This unit represents a substantial investment and requires careful attention to maintain good working order. Observe the following during operation and maintenance:

• Do not allow unauthorized or unqualified personnel to access the unit.
• Do not access electrical components without switching off the main switch and power supply.
• Do not access electrical components without an insulating platform, especially if water or moisture is present.
• Refrigerant circuit operations and work on components under pressure must be carried out exclusively by qualified personnel.
• Compressor replacement must be carried out exclusively by qualified personnel.
• Sharp edges and surfaces can cause injury; use adequate protection.
• Do not introduce solid objects into water pipes while the unit is connected.
• Do not remove any protections of moving parts.

In case of sudden unit stop, follow instructions in the Control Panel Operating Manual.

It is strongly recommended to perform installation and maintenance with others.

WARNING: Avoid installing the unit in areas that could be dangerous during maintenance operations, such as platforms without parapets or railings.

Maintenance

This unit must be maintained by qualified technicians. Ensure all security precautions are taken before starting any work.

Neglecting maintenance can degrade unit performance and functionality.

Two maintenance levels are available, based on application type (critical/noncritical) and installation environment (highly aggressive).

Critical applications include process cooling and data centers.

Highly Aggressive Environments include:

• Industrial environments (fumes, chemical processes).
• Coastal environments.
• Highly polluted urban environments.
• Rural environments near animal excrement, fertilizers, or diesel exhaust.
• Desert areas with risk of sandstorms.
• Combinations of the above.

Units in highly aggressive environments may experience faster corrosion. Periodic washing of frame surfaces with water and detergents is recommended. Repaint any exposed parts to prevent progressive deterioration. For salt deposits, rinse with fresh water.

WARNING: All electrical maintenance must be performed by qualified personnel. Ensure the system is switched off and the main switch is open. Failure to observe this rule could result in serious personal injury.

Electrical maintenance includes:

1. Comparing the absorbed current by the compressor to the rated value.
2. Performing security checks at least every three months to verify functionality. Monitor operation points and adjust or replace components as needed. Check pump interlocks and flow switches to ensure they interrupt the control circuit if they intervene.

Table 7: Standard Routine Maintenance Plan

Notes:

• 1. Monthly activities include all weekly ones.
• 2. Annual (or early season) activities include all weekly and monthly activities.
• 3. Daily reading of operating values maintains high observational standards.
• 4. Check for any dissolved metals.
• 5. Clean condenser banks and water heat exchangers with appropriate chemicals. Particles and fibres can clog exchangers, especially if water is rich in calcium carbonate. Increased pressure drops or decreased thermal efficiency indicate clogged exchangers. In environments with high airborne particles, more frequent cleaning of the condenser bank may be necessary.
• 6. Units placed or stored in a Highly Aggressive Environment for long periods without operation are still subject to routine maintenance.

Table 8: Routine Maintenance Plan for Critical Application and/or Highly Aggressive Environment

Notes:

• 7. Monthly activities include all weekly ones.
• 8. Annual (or early season) activities include all weekly and monthly activities.
• 9. Daily reading of operating values maintains high observational standards.
• 10. Check for any dissolved metals.
• 11. Clean condenser banks and water heat exchangers with appropriate chemicals. Particles and fibres can clog exchangers, especially if water is rich in calcium carbonate. Increased pressure drops or decreased thermal efficiency indicate clogged exchangers. In environments with high airborne particles, more frequent cleaning of the condenser bank may be necessary.
• 12. Units placed or stored in a Highly Aggressive Environment for long periods without operation are still subject to routine maintenance.

Service and Limited Warranty

All units are factory tested and guaranteed for 12 months from the first start-up or 18 months from delivery. These units are developed and constructed to high quality standards ensuring years of failure-free operation. Maintenance is required even during the warranty period, from installation until commissioning.

Daikin strongly advises stipulating a maintenance contract with a manufacturer-authorized service provider for efficient and problem-free service.

Operating the unit inappropriately, beyond its limits, or not performing proper maintenance as per this manual can void the warranty. Observe the following points to conform to warranty limits:

1. The unit cannot function beyond specified limits.
2. Electrical power supply must be within voltage limits and without voltage harmonics or sudden changes.
3. Three-phase power supply must not have an unbalance between phases exceeding 3%. The unit must remain off until the electrical problem is solved.
4. No safety device (mechanical, electrical, or electronic) must be disabled or overridden.
5. Water used for filling the water circuit must be clean and suitably treated. A mechanical filter must be installed at the point closest to the BPHE inlet.
6. The BPHE water flow value must be included in the declared range for the unit, as per CSS selection software.

Before Starting

WARNING: The unit should not be started, even for a short period, before the following pre-commissioning checklist is filled out completely.

Table 9: Standards steps to go through before starting the unit

I do confirm having executed and checked all the above-mentioned items.

Date: _________________________ Signature: _________________________

Keep for future reference