Jetson FWCD Series, Installation Operation & Maintenance, Page: 39 / 96

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39
Application Information
Evaporator Design Data
The system can start and pull down with up to
90°F
entering fluid temperature. For
continuous operation, it is recommended that
the entering fluid temperature not exceed 75°F.
The maximum sustained leaving chilled-fluid
temperature is 65°F. The chiller with
standard
evaporator must not be operated with a leaving
water temperature of less than 42°F for a plain
water application. The chiller with
high-
capacity evaporator must not be operated with
a leaving water temperature of less than 40°F
for a plain water application. For evaporator
loops containing the appropriate amount of
glycol, the chilled water leaving temperature
range can be shifted to 15°F to 65°F. When
lower leaving fluid temperatures are required,
an appropriate glycol solution must be used.
The solution must have a freezing point at least
15°F lower than the design leaving fluid
temperature. The brine solution must also be
properly
inhibited to provide suitable
corrosion protection.
The evaporator minimum and maximum flow
rates are listed in General Data Table. In
general, the listed flow rate ranges will develop
temperature differentials across the evaporator
between 7°F to 20°F. If your application
conditions do not fit these requirements, please
contact Jetson Innovations.
For all FWCD Series chiller applications, the
flow to the evaporator must be proven using a
chilled water flow-proving device. A factory-
provided paddle style liquid flow switch is
provided with a NEMA Type 4X enclosure for
field-installation.
Condenser Design Data
Standard condenser entering water
temperature range for the FWCD Series chiller
is 65°F to 125°F. The condenser leaving water
temperature (LWT) maximum is 125°F for
shell-and-tube condensers and 140°F for
brazed-plate condensers, and the condenser
LWT minimum is 70°F. When the condenser
LWT is lower than 70°F, the refrigerant
condensing temperature can drop below 80°F
and fall outside of the FWCD Series
compressor’s operating envelope. For these
applications, provisions must be made to
control the condenser water that results in a
stable refrigerant condensing temperature /
pressure that remains above 80°F (235 psig)
throughout all steady state, part load and
transient operating conditions. The integral
factory-installed condenser water regulating
valve option is ideal for these applications and
is highly recommended.
The condenser minimum and maximum flow
rates are listed in the General Data table. In
general, the listed flow rate ranges will develop
temperature differentials across the condenser
between 5°F to 30°F. If your application
conditions do not fit these requirements, please
contact the Jetson Innovations.
All Jetson modular chillers have two
compressors in each individual module. Both
of these compressors are served by common
water flow. In a typical water-cooled
application with nominal water flows of 2.4
gpm/ton through the evaporator BPHE (brazed
plate heat exchanger) and 3.0 gpm/ton through
the condenser, the delta temperature entering
and leaving both heat exchangers will be 10°F
with both compressors running, and 5°F with
one compressor running.
Condenser Heat Recovery Operation
At a time when energy costs are high and
continue to rise, reducing energy usage has
become increasingly important. By using a
FWCD Series chiller with heat recovery,
utilization of energy can be improved by using