Daikin EWWP014KBW1N Operation Manual Download

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Operation manual

EWWP014~065KBW1N

Packaged water-cooled water chillers

4PW61660-1A – 04.2012

Function of the main components

Figure -

Functional diagram

As the refrigerant circulates through the unit, changes in its state or
condition occur. These changes are caused by the following main
components:

■

Compressor
The compressor (M*C) acts as a pump and circulates the
refrigerant in the refrigeration circuit. It compresses the
refrigerant vapour coming from the evaporator to a pressure at
which it can easily be liqueﬁed in the condenser.

■

Condenser
The function of the condenser is to change the state of the
refrigerant from gaseous to liquid. The heat gained by the gas in
the evaporator is discharged through the condenser and the
vapour condenses to liquid.

■

Filter
The ﬁlter installed behind the condenser removes small particles
from the refrigerant to prevent blockage of the tubes.

■

Expansion valve
The liquid refrigerant coming from the condenser enters the
evaporator via an expansion valve. The expansion valve brings
the liquid refrigerant to a pressure at which it can easily be
evaporated in the evaporator.

■

Evaporator
The main function of the evaporator is to take heat from the
water that ﬂows through it. This is done by turning the liquid
refrigerant, coming from the condenser, into gaseous refrigerant.

■

Water in/outlet connections
The water inlet and outlet connection allow an easy connection
of the unit to the water circuit of the air handling unit or industrial
equipment.

Safety devices

The unit is equipped with

General safety devices

: shut down all

circuits and stop the whole unit.

■

I/O PCB (A2P) (input/output)
The I/O PCB (A2P) contains a reverse phase protector.
The reverse phase protector detects if the 3 phases of the power
supply are connected correctly. If a phase is not connected or if
2 phases are inverted, the unit can not start up.

■

Overcurrent relay
The overcurrent relay (K*S) is located in the switch box of the
unit and protects the compressor motor in case of overload,
phase failure or too low voltage. The relay is factory-set and may
not be adjusted. When activated, the overcurrent relay has to be
reset in the switch box and the controller needs to be reset
manually.

■

High-pressure switch
The high-pressure switch (S*HP) is installed on the discharge
pipe of the unit and measures the condenser pressure (pressure
at the outlet of the compressor). When the pressure is too high,
the pressure switch is activated and the circuit stops.
When activated, it resets automatically, but the controller needs
to be reset manually.

■

Low pressure switch
The low-pressure switch (S*LP) is installed on the suction pipe
of the unit and measures the evaporator pressure (pressure at
the intlet of the compressor). When the pressure is too low, the
pressure switch is activated and the circuit stops.
When activated, it resets automatically, but the controller needs
to be reset manually.

S4LP

S1HP

R3T

R5T

Q1D

M1C

R4T