Daikin EWAQ170F-XR [30/67] Operating limits

OPERATING LIMITS

The above data are referred to:

- Fan 800 mm diameter

- Fan speed 700 rpm or 705 rpm

Legend:

A = External Static Pressure (Pa)

B = Cooling Capacity (kW) Correction factor

C = Compressor Power Input (kW) Correction factor

D = Reduction of Maximum Condenser Inlet Air Temperature (°C)

Water content in cooling circuits

The cooled water distribution circuits should have minimum water content to avoid

excessive compressors start and stop. In fact, each time the compressor starts up, an excessive quantity of oil goes from the

compressor sum

p and simultaneously there is a rise in the temperature of the compressor motor’s stator due to the inrush current

during the start-

up. To prevent damage to the compressors, have been envisaged the application of a device to limit frequent stops and

restarts.

During the span of one hour there will be no more than 6 starts of the compressor. The plant side should therefore ensure tha

t the

overall water content allows a more constant functioning of the unit and consequently greater environmental comfort. The

minimum

water content per unit should be calculated with a certain approximation using this simplified formula:

For 4 compressors unit

M (liters) = (0.4349 x DT(°C) + 2.6158) x P(kW)

For 6 compressors unit

M (liters) = (0.5554) x P(kW)

where:

M = minimum water content per unit expressed in litres

P = cooling capacity of the unit expressed in kW

ΔT = evaporator entering / leaving water temperature difference expressed in °C

This formula is valid for standard microprocessor parameters. For more accu

rate determination of quantity of water, it is advisable to

contact the designer of the plant.

Water charge, flow and quality

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