19XL
Hermetic Centrifugal Liquid Chiller
50/60 Hz
HCFC-22 - 300 to 600 Nominal Tons (1055 to 2110 kW)
HFC-134a - 200 to 530 Nominal
Tons (700 to 1865 kW)
The 19XL is one of the most
technologically advanced chiller available. Its innovative combination
of advancements in compression, heat exchange, and direct digital
control technologies result in an efficient, reliable, and flexible
design.
Features/Benefits
The positive pressure design:
Reduces the size of the
chiller by up to 35%
as compared to low-pressure designs, resulting in lower floor
space requirements and easier installation.
Allows for easier installation
within confined plant rooms when compared to similar chillers
of equal capacity. This is due to its modular construction and
smaller components.
Eliminates the need for
a purge unit, which
reduces refrigerant loss and eliminates purge vent and water piping.
Fulfills ASME refrigerant
side construction requirements through rigorous pressure testing
and a design that ensures a leak tight assembly.
Allows for storage of refrigerant
in the chiller during servicing
with the addition of liquid line and compressor discharge isolation
valves.
Reduced operating costs
are achieved through advancements in three key technologies:
Compression:
Tunnel diffuser,
originally developed through the use of jet engine technology,
is now utilized by Carrier to increase centrifugal compressor
peak operating efficiency. Higher efficiencies are possible by
reducing friction losses through the diffuser section of the compressor.
New impeller
with aerodynamically contoured blade profiles, high back sweep
blades, and intermediate splitter blades improves the efficiency
of refrigerant compression.
Reduced mechanical losses
and increased efficiency
are achieved by optimizing the amount of oil required in the gear
mesh, reducing friction in the journal bearings, reducing thrust
loads, and streamlining the motor rotor to reduce windage losses.
High efficiency hermetic
motors cooled by
liquid refrigerant reduce the electrical losses of the compressor.
Heat Exchange:
The latest heat transfer
technology was
used to improve tube surface efficiency, while maintaining a compact
design. Water side and refrigerant side tube enhancements reduce
the overall resistance to heat transfer, resulting in improved
heat transfer efficiency.
Optimizing tube spacing
allows peak heat transfer efficiency to be achieved when using
the new advanced tube surfaces.
Integral FLASC (Flash Subcooler)
cools the condensed liquid refrigerant to a lower temperature;
consequently increasing the refrigeration effect and resulting
in reduced compressor power consumption.
Variable refrigerant metering
ensures a liquid seal at all operating conditions to eliminate
performance losses from unintentional hot gas bypass.
Direct Digital Controls:
Precise chilled water temperature
control is maintained
by the micro-processor controller which accurately positions the
compressor inlet guide vanes in response to changes in cooling
load.
Occupancy schedules
can be programmed into the controller to ensure that the chiller
only operates when cooling is required.
Ramp loading
ensures a smooth pulldown of water loop temperature while preventing
a rapid increase in compressor power consumption during the pulldown
period.
Demand limiting
is included to limit the power draw of the chillers during peak
loading conditions. When incorporated into the Carrier Comfort
Network (CCN) building automation system, a red line command will
hold all chillers at their present capacity and prevent any other
chillers from starting. If a loadshed signal is received, the
compressors are unloaded to avoid high demand charges whenever
possible.
Chilled water reset
can be done manually or automatically from the building management
system which saves energy when warmer chilled water can be utilized.
With the addition of the
Chillervisor chiller plant management controller,
the entire chiller plant, including chillers, pumps, valves and
cooling towers, is automatically controlled to reduce the overall
plant power consumption. Multiple chillers are sequenced to ensure
the lowest possible power consumption during reduced loading conditions.
Increased reliability, resulting in less downtime and longer life, is achieved through the use of:
The hermetic compressor
eliminates shaft seals and associated refrigerant and oil leakage,
as well as motor heat rejection to the plant room. Both faults
are characteristic of open compressor designs.
The single stage design
eliminates additional moving parts such as second-stage adjustable
guide vanes and multiple FLASCs, which are characteristic of some
multistage compressors.
Steel backed, babbitt lined,
compressor sleeve bearings
and a Kingsbury-type, self-leveling thrust bearing increase reliability.
Cool-running hermetic motors
have been proven reliable through more than 25 years of service.
Stationary tunnel diffuser
requires no moving or wearing parts, which further enhances reliability.
Microprocessor controls
eliminate the need for pressure and temperature switches and pressure
gages.
Circuit boards
are encased in plastic modules to eliminate damage and abuse.
Microprocessor controls simplify use, improve chiller protection, reduce trouble-shooting time, and provide additional information to the operator. The controls feature a:
16 line by 40 character
display which provides
''all in one glance'' access to key chiller operating data and
simplifies use by eliminating ''coded'' messages. It displays
over 125 operating and diagnostic conditions to reduce troubleshooting
time.
Microprocessor monitors
over 100 functions
to protect the chiller from abnormal conditions.
365-day real time clock
allows the operator to program a yearly schedule for the week,
weekends, and holidays.
Battery backup provides
protection during power failures
and eliminates time consuming control reconfiguration.
Alarm file maintains the
last 25 time and date stamped alarm and alert messages
in memory to reduce troubleshooting time and cost.
Capacity override mode
keeps the chiller on line to reduce nuisance shutdowns. This function
unloads the compressor whenever key safety limits are approached.
An automated controls test
can be executed prior to start-up to verify that the entire control
system is functioning properly.
Optional modules
offer unique control expandability - chilled water reset and demand
limit from remote sources and more.
Additional features simplify installation and reduce installation time and cost:
Refrigerant-cooled oil
cooler eliminates
auxiliary water piping.
Optional unit-mounted starters
provide single point power connection and are fully tested prior
to shipment from the factory.
Factory tested before shipment provides peace of mind while protecting your chiller investment:
ASME inspections of all pressure vessels occur at major points of assembly.
ASME rated materials and processes
result in the ''U'' stamp, a sign of pressure vessel integrity.
Compressors are 100% run-tested
before mounting
as an extra quality step.
Hydrostatic, vacuum and
pressure testing of the assembled chillers
ensures leak integrity.
Controls and optional unit-mounted starter are tested after mounting to verify proper electrical functioning.