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6.4 REFRIGERATION SYSTEM
The Refrigeration System consists of all the components which handle R-404A. This
is a hermetically sealed closed-loop system. Referring to Figure 1 and following the
phantom “
REFRIG
(
R-404A
)
FLOW
,” refrigerant is shown leaving the evaporator section
where, in the process of removing heat, it is changed from a low pressure liquid into
a low pressure gas. This gas enters the suction side of the compressor where it is
compressed into a high pressure gas. The high pressure gas is cooled in the
condenser section until it becomes a high pressure liquid. It then goes through a
permanent filter dryer that ensures the refrigeration system is free of contaminants.
A small diameter capillary tube (expansion valve on water-cooled dryers) meters the
refrigerant for introduction into the evaporator. The refrigerant pressure is reduced
upon entering the evaporator where as it evaporates, heat is removed from the
thermal mass fluid.
6.5 THERMAL MASS CIRCULATING SYSTEM
The thermal mass fluid in a ZEKS HeatSink™ dryer is continuously circulated in a
closed pump loop system. Referring to Figure 1 and following the dashed “
THERMAL
FLUID
” line, the heat is removed from the fluid in the evaporator by the refrigeration
system. The thermal mass reservoir is sized to minimize refrigeration cycles during
reduced air load periods. The thermal mass fluid is pulled from the bottom of the
reservoir and pumped through the chiller, removing heat from the air, and is then
returned to the evaporator. The pump utilized on a ZEKS HeatSink™ dryer is a
maintenance-free, quiet cartridge circulator pump similar to those used in residential
water systems. While the refrigeration system cycles on and off based on loading
conditions, the circulating pump runs continuously to maintain flow through the chiller
at all times. Note that when the power switch is set to the off position, the circulating
pump will not operate.
