CHAPTER II
SEC I CONT. · SEC II
ambient for the removal of heat. Occasionally, a small
fan is used for more efficient cooling.
With the forced convection condenser a high
capacity fan is used to force the air through the
condenser enabling a more rapid heat transfer and a
smaller condenser design.
(b)
Water-Cooled
Condenser
-
Water
Cooled
condensers are used in areas of adverse environment.
They are made of a double coil, refrigerant and water,
bonded together for heat transfer. A water metering
valve controlled by the operating conditions of the
refrigeration system, regulates the flow of water through
the water coil.
3.
STRAINER - REFRIGERANT
The refrigerant strainer is a part of the liquid line and is
located at the outlet from the condenser. The strainer is
used to guard against blockage of the capillary tube.
4.
CAPILLARY TUBE
The small bore capillary tube restricts refrigerant flow
and creates the pressure difference in the refrigeration
system. When bonded to the suction line, it acts as a
heat exchanger giving the refrigerant a secondary
cooling effect before entering the evaporator.
5.
EVAPORATOR COIL
The evaporator coil is solder bonded to the water cooling
tank or coil and is a part of the cooling unit. The
evaporator coil transfers the heat from the water to the
refrigerant causing it to boil as a low temperature vapor.
6.
ACCUMULATOR
The accumulator is a part of the cooling unit. It acts as a
trap allowing only refrigerant in a gaseous state to return
to the compressor.
7.
THERMOSTAT
The thermostat, located in the compressor compartment,
controls the water temperature by starting and stopping
of the compressor as required.
This is accomplished by the power element
inserted in the bulb well of the cooling unit.
The power element of the thermostat is filled
with a volatile refrigerant which exerts a force when
warmed and relieves a force when cooled. This action
causes the electrical contacts to open and close.
Some coolers are provided with an extra
thermostat wired in series with the control thermostat.
This thermostat has a lower setting to prevent freezing of
the water system should the control thermostat fail.
There is no adjustment provided with this freeze
protection thermostat.
SECTION II - DESCRIPTION OF WATER SYSTEM
SCHEMATIC-WATER CIRCUIT
1.
COOLING UNIT
The cooler assembly is located in a sealed and insulated
enclosure of the water cooler. The basic types of the
cooler assembly designs are the tank, coil-on-coil and
shell.
(a)
Tank Type Cooling Assembly - The tank type
cooler assembly has the evaporator solder bonded
to the exterior of the tank. The ac-
TANK TYPE COOLING UNIT
cumulator is a part of the cooler assembly. The tank has
a water inlet and a water outlet connected to the water
regulating valve and glass filler. It also has a thermostat
bulb
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