Carrier Aquaforce 30XA Series Скачать руководство пользователя страница 44

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11.2.1 - Evaporator

30XA chillers use a flooded multi-tube evaporator. The water

circulates in the tubes and the refrigerant is on the outside
in the shell. One vessel is used to serve both refrigerant
circuits. There is a centre tube sheet which separates the two
refrigerant circuits. The tubes are 3/4” diameter copper with

an enhanced surface inside and out. There is just one water

circuit, and depending on the size of the chiller, there may
be one, two or three water passes.

The units have three refrigerant circuits with two evaporators

connected in series on the heat transfer fluid.

The evaporator has a thermal insulation of 19 mm thick
polyurethane foam, an aluminium sheet (option) and is
equipped with a water drain and purge.

The water connection of the heat exchanger is a Victaulic
connection. As an option the evaporator is available with
frost protection (evaporator frost protection option).

The products that may be added for thermal insulation of
the containers during the water piping connection procedure
must be chemically neutral in relation to the materials and
coatings to which they are applied. This is also the case for
the products originally supplied by Carrier.

11.2.2 - Oil separator

In these units, the oil separator is a pressure vessel that is
mounted under the outside vertical condenser coils.
Dis-charge gas at the compressor outlet is directed
towards the bottom of the oil separator ring and most of the
oil separates from the gas by strong deceleration and by

gravity. The gas then flows through a wire mesh screen

where the remaining oil is separated by coalescence and

flows to the bottom of the ring. The gas is now free from

oil and leaves the ring at the top towards the condenser.

The oil separator is equipped with a trace heater regulated
by the control.

11.2.3 - Economiser function

The economiser function includes a liquid line valve, a

filter drier, two EXVs, a plate heat exchanger as well as

protection devices (fuse or valve).

At the condenser outlet a part of the liquid is expanded via
the secondary EXV in one of the heat exchanger circuits
and then returns as gas at the compressor economiser. This
expansion permits increase of the liquid sub-cooling of the

rest of the flow that penetrates the evaporator via the prin-

cipal EXV. This permits increasing the cooling capacity of

the system as well as its efficiency.

11.3 - High-pressure safety switch

30XA units are equipped with high-pressure safety switches.

In accordance with the applicable code the high-pressure
switches with manual reset, called PZH (former DBK), may
be backed up by high-pressure switches that require
resett-ing with a tool. The high-pressure switches that
require resetting with a tool are called PZHH (former
SDBK). If a PZHH cuts out, the corresponding PZH in
the same com-pressor is faulty and must be replaced. The
PZHH must be reset with a blunt tool with a diameter of
less than 6 mm. Insert this tool into the opening on the
pressure switch and push the reset button in this location.

These pressure switches are located at the discharge of each
compressor.

11.4 - Condensers

30XA coils are all-aluminium micro-channel condensers.
Optional coils with internally grooved copper tubes with

aluminium fins are also available (options 254 and 255).

11.5 - Fans

The fans are axial Flying Bird fans equipped with rotating
shroud and made of composite recyclable material. Each

motor is fixed with transverse supports. The motors are

three-phase, with permanently lubricated bearings and
insulation class F (level IP55).

According to the Regulation No. 327/2011 implementing Directive 2009/125/EC with regard to ecodesign requirements for
fans driven by motors with an electric input power between 125 W and 500 kW.

Product

30XA

Option

Standard

Option 119

Global fan efficiency

35.5

39.3

Measurement category

Efficiency category

static

Energy efficiency target N(2015)