Daikin EWAD620-C17C-SL, Руководство по обслуживанию

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ESIE10-01 General Outline
Part 1 – System Outline 1–9
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1
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1.4 General Characteristics
Cabinet and
structure The cabinet is made of galvanized steel sheet and painted to provide a high resistance to corrosion.
Colour Ivory White (Munsell code 5Y7.5/1) (±RAL7044). The base frame has eye-hook for lifting the
unit with ropes for an easy installation. The weight is uniformly distributed along the profiles of the base
and this facilitates the arrangement of the unit.
Screw compressors
with integrated oil
separator The compressors are semi-hermetic, single-screw type with gate-rotor (with the latest high-strength
fibre reinforced star material). Each compressor has an asymmetric slide regulation managed by the
unit controller for infinitely modulating capacity. An integrated high efficiency oil separator maximizes
the oil separation. Standard Start is Wye-delta (Y-
Δ
) type.
Ecological HFC
134a refrigerant The compressors have been designed to operate with R-134a, ecological refrigerant with zero ODP
(Ozone Depletion Potential) and very low GWP (Global Warming Potential) that means low TEWI
(Total Equivalent Warming Impact).
Evaporator The units are equipped with a Direct Expansion shell&tube evaporator with copper tubes rolled into
steel tubesheets. The evaporators are single-pass on both the refrigerant and water sides for pure
counter-flow heat exchange and low refrigerant pressure drops. Both attributes contribute to the heat
exchanger effectiveness and total unit's outstanding efficiency. The external shell is covered with a
20 mm closed cell insulation material. Each evaporator has 2 or 3 circuits, one for each compressor
and is manufactured in accordance to PED approval. The evaporator water outlet connections are
provided with Victaulic Kit (as standard).
Condenser coils The condenser is manufactured with internally enhanced seamless copper tubes arranged in a
staggered row pattern and mechanically expanded into lanced and rippled aluminium condenser fins
with full fin collars. An integral sub-cooler circuit provides sub-cooling to effectively eliminate liquid
flashing and increase in cooling capacity without increasing the power input.
Condenser coil fans The condenser fans are propeller type with high efficiency design blades to maximize performances.
The material of the blades is glass reinforced resin and each fan is protected by a guard. Fan motor is
thermally protected (as standard) by internal thermal motor and protected by circuit breaker installed
inside the electrical panel as a standard. The motors are IP54.
Electronic
expansion valve The unit is equipped with the most advanced electronic expansion valves to achieve precise control of
refrigerant mass flow. As today's system requires improved energy efficiency, tighter temperature
control, wider range of operating conditions and incorporate features like remote monitoring and
diagnostics, the application of electronic expansion valves becomes mandatory. Electronic expansion
valve proposes features that makes it unique: short opening and closing time, high resolution, positive
shut-off function to eliminate use of additional solenoid valve, continuous modulation of mass flow
without stress in the refrigerant circuit and corrosion resistance stainless steel body. Electronic
Expansion Valves are typically working with lower
Δ P between high and low pressure side, than a
thermostatic expansion valve. The electronic expansion valve allows the system to work with low
condenser pressure (winter time) without any refrigerant flow problems and with a perfect chilled water
leaving temperature control.