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Theory of Operation
Model 506 (UC Ice Maker)
Model 506 (UC Ice Maker)
3-2
#3752200 - Revision B - May, 2006
OPERATING SYSTEMS
There are three operating systems in the icemaker:
•
Refrigeration System
•
Water System
•
Electrical System
Refrigeration System
The following components have been listed in the order
of refrigerant flow, with an explanation of their function
as part of the refrigeration system.
•
Compressor:
The compressor creates a high side
and low side pressure difference in the refrigeration
system by compressing the refrigerant gas, thus rais-
ing the pressure and temperature. During the ice
making cycle the compressor pushes this high-pres-
sure/high-heat gas to the condenser.
•
Condenser:
The high-pressure/high-heat gas travels
through the condenser, where heat is dissipated by
cooler air being drawn over the condenser tubing by
the condenser fan. This changes the gas into a high-
pressure/warm liquid that then enters the filter-drier.
•
Filter-Drier:
The high-pressure/warm liquid travels
through the filter-drier, which removes moisture from
the refrigerant before it enters the capillary tube.
•
Capillary Tube:
The warm liquid refrigerant travels
through a skinny capillary tube which is wrapped
around the suction line and accumulator. As warm
liquid refrigerant travels through the capillary tube, it
gives up heat to the cool vapor refrigerant in the
accumulator and to the cool refrigerant gas traveling
through the suction line. As refrigerant in the capillary
tube gives up heat, the pressure drops, so it is a low-
pressure/cool liquid before it enters the evaporator.
•
Evaporator:
A dramatic pressure drop occurs as the
low-pressure/cool liquid refrigerant leaves the small
diameter capillary tube and enters the larger diameter
evaporator tubing, and the refrigerant begins to
vaporize. This vapor travels through the evaporator
absorbing heat from the water being sprayed on the
evaporator. This cool vapor then enters the accumu-
lator.
•
Accumulator:
Another pressure drop occurs as the
cool vaporized refrigerant leaves the evaporator tub-
ing and enters the larger diameter accumulator tub-
ing. Any liquid or vaporized refrigerant that may
remain at this point is converted to gas. The capillary
tube is wrapped around the accumulator to give up
heat to the refrigerant in the accumulator before it
enters the suction line.
•
Suction Line:
The cool gas travels through the suc-
tion line which is also partially wrapped with the capil-
lary tube. As this cool refrigerant gas travels through
the suction line it too absorbs heat from the warm liq-
uid refrigerant traveling through the capillary tube.
This assures that it is a luke warm gas before it
enters the compressor, where the process begins
again.
NOTE:
There is an additional component in the ice
maker refrigeration system which is used during the
harvest cycle, this component is called the hot gas
valve. Its function is described below:
•
Hot Gas Valve:
During a harvest cycle, the hot gas
valve interrupts the flow of high-pressure/ high-heat
gas from the compressor, diverting it past the con-
denser, filter-drier and capillary tube, directly to the
evaporator. This high-pressure/high-heat gas warms
the evaporator so that the ice slab releases from the
evaporator.
Evaporator
Accumulator
Capillary Tube
Heat
Exchanger
Suction
Tube
Compressor
Drier
Condenser
Condenser
Accumulating
Tube
Hot Gas
Valve
Figure 3-1. Refrigeration Overview
