Carrier 23XRV 사용자 설명서

Variable speed capacity control elimi-
nates slide valves, their associated loss-
es, and their potential failure modes.
Component count (both rotating and
total) has been minimized assuring
maximum reliability under a wide
range of operating conditions.

High efficiency

Per AHRI 550/590, chillers operate at
design conditions less than one percent
of the time. As a result, superior part
load efficiency is required for today’s
chilled water applications. The Ever-
green

23XRV screw chiller maximizes

chiller efficiency by optimizing com-
pressor operation. Electric power con-
sumption drops dramatically when the
motor speed slows. The 23XRV screw
chiller delivers industry-leading inte-
grated part load values (IPLV) in an ex-
tremely broad range of applications
and climates.

Environmental leader

Carrier has long been committed to
the environment and its sustainability.
The Evergreen 23XRV screw chillers
provide our customers with a high-
efficiency, chlorine-free, long-term
solution unaffected by refrigerant
phase outs. Carrier’s decision to utilize
non-ozone depleting HFC-134a refrig-
erant provides our customers with a
safe and environmentally sound
product without compromising effi-
ciency. In addition, HFC-134a was
given an A1 safety rating by ASHRAE
(American Society of Heating,
Refrigerating and Air Conditioning
Engineers), meaning that it is the safest
refrigerant available.

Quality design

Positive displacement compres-
sion — Positive displacement com-
pression ensures stable operation
under all load conditions without the
possibility of compressor surge.
Superior oil management/cold
condenser water operation — All
Evergreen 23XRV chillers regulate oil
temperature, viscosity and pressure. A
patented process assures high quality
oil is delivered to the compressor bear-
ings by a positive displacement pump.
Bearing lubrication is assured, allowing
continuous operation with cold
condenser water at all loads. Screw
chillers no longer need to rely on dif-
ferential system pressure to effectively
lubricate the compressor. Should the

input power to the chiller be lost, the
system design assures proper lubrica-
tion of the bearings during coast down.
Small footprint — The Evergreen
23XRV chiller’s positive pressure
design reduces the chiller size by up
to 35% compared to negative-pressure
designs. Extremely high compression
efficiencies allow for compact,
high-efficiency chillers that require less
mechanical room floor space.
Constant or variable evaporator
flow — The 23XRV chiller combines
the advantages of positive displace-
ment compression with variable speed
capacity control. This process provides
a chiller that reacts substantially better
than chillers equipped with inlet guide
vanes or slide valves. This allows for
easier transition when bringing addi-
tional chillers on line in multiple chiller
plants and eliminates any possibility of
surge, regardless of the changes in the
system.
Low harmonic distortion — The
Evergreen 23XRV chiller will generate
less than 5% total harmonic distortion
at the input to the VFD (variable
frequency drive) without the use of
any external filters or line reactors.
This assures the VFD alone cannot
exceed the IEEE-519 standard for
distortion at the point of common
coupling. Ultra-low harmonics can
eliminate the need for complicated
harmonic system studies.
Low starting current (inrush) —
The inrush current is limited to the
chiller full load amps (rated load
amperes). No other starting means can
equal this level of starting current. The
combination of low current and ultra
low harmonics can reduce backup
generator size requirements.

0.99 power factor — The Ever-
green 23XRV chiller can operate at up
to 0.99 displacement power factor,
which helps building owners avoid
power factor penalties and decreases
electrical losses in cables and trans-
formers. High power factor may also
reduce KVA requirements, saving elec-
trical system costs on new projects or
freeing up electrical resources on exist-
ing systems operating near their maxi-
mum capacity.
Refrigerant-cooled VFD — Refrig-
erant cooling of the VFD minimizes
VFD size and ensures proper cooling
of the transistors for extended life.
Using R-134a refrigerant instead of
water also eliminates costly mainte-
nance associated with the water cool-
ing pump, heat exchanger and rubber
tubing used with water-cooled VFDs.
Optional seismic kit — A seismic
isolation package is available to meet
International Building Code and ASCE
7 seismic qualification requirements in
concurrence with ICC ES AC156 Ac-
ceptance Criteria for Seismic Qualifica-
tion by Shake-Table Testing of Non-
structural Components and Systems.
Hermetic motor — The Evergreen
23XRV chiller utilizes motors that are
hermetically sealed from the machine
room. Cooling is accomplished by
spraying liquid refrigerant on the
motor windings. This highly efficient
motor cooling method results in cooler-
running motors than could be realized
with air-cooled designs of the same
type.

In addition, Carrier’s hermetic de-

sign eliminates:
• Compressor shaft seals that require

maintenance and increase the likeli-
hood of refrigerant leaks.

Features/Benefits (cont)

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