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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.
In case of sudden stop of the unit, follow the instructions on the Control Manual Operating Manual which is part of
the on-board documentation delivered to the end user with this manual.
It is recommended to perform installation and maintenance with other people. In case of accidental injury or unease, it
is necessary to:
- keep calm
- press the alarm button if present in the installation site
- move the injured person in a warm place far from the unit and in rest position
- contact immediately emergency rescue personnel of the building or if the Health Emergency
- wait without leaving the injured person alone until the rescue operators come
- give all necessary information to the the rescue operators
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.
Low Condenser Water Temperature Operation
When ambient wet bulb temperature are lower than design, the condenser water temperature can be allowed to fall.
Lower temperatures will improve chiller performance.
Daikin centrifugal chillers all across the range are equipped with electronic expansion valves (EXV) and will start and
run with entering condenser water temperatures as low as shown in Figure 3 or as calculated from the following equation
on which the curves are based.
WARNING
Service
D–EIMWC00808-16HU - 14/64
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