Daikin EWWD VZ Series, Installation, Maintenance And Operating Manual

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Chilled water control sensor
The water cooled EWWD VZ unit is equipped with a microprocessor. Be careful when working around the unit to
avoid damaging cables and sensors. Check cables before starting the unit. Prevent rubbing of the cables on the
frame or other components. Make sure the cables are securely locked. If the temperature sensor is removed for
maintenance, do not eliminate the conductive paste in the well and replace the sensor correctly. After replacing
the sensor, tighten the lock nut to prevent accidental slipping.
Safety Valve
Each exchanger (evaporator and condenser) is provided with a safety valve installed on an exchange valve that
allows maintenance and periodic checks, without losing a significant amount of refrigerant. Do not leave the
safety valve in the intermediate position.
WARNING
To prevent damage due to R134a gas inhalation, do not release the refrigerant in the air or other indoor places.
The safety valves must be connected externally in accordance with the regulations in the place of installation.
The installer is responsible for connecting the safety valve to the purge pipe and pipe dimensioning. In this
regard, refer to the harmonized standard EN13136 to dimension the drain pipes to be connected to the safety
valves
Open the isolation and/or shut off valves
Before powering the machine and thus starting the compressors, open all valves that were closed at the factory
for shipping.
The valves to be opened are:
1. Valve (optional) installed on the compressor line
2. Oil return pipe shutoff valves (jet pump). These valves are positioned below the evaporator sleeve in the
vicinity of the jet pump.
3. Liquid line valve installed under the condenser.
4. Oil valves installed on the line that feeds the compressor lubrication system. This line comes from the
bottom of the oil separator located inside the condenser.
5. Valve (optional) installed on the compressor pump line.
Electrical connections
The unit must be connected with in the proper section copper cables relative to the plate absorption values and
in accordance with applicable electrical regulations.
Daikin Applied Europe S.p.A. cannot be held liable for improper electrical connections.
Warning
The connections to the terminals must be made with copper terminals and cables.
The electrical connection must be made by qualified personnel.
There is a risk of electric shock
The electrical panel must be connected keeping the correct phase sequence.
Phase imbalance
In a three-phase system, excessive imbalance between the phases is the cause of motor overheating. The
maximum allowed voltage imbalance is 2%, calculated as follows:
imbalance %= (Vx-Vm) x 100 =
Vm
Vx = phase with greatest imbalance