5
Kooltronic Air Conditioners are required when the equipment operating temperature must be kept near or lower
than the ambient room temperature, and/or the cabinet must be sealed from dust, fumes, oil, corrosives
and other contaminants. This Air Conditioner utilizes a "Closed-Loop Cooling System" to ensure optimum
performance of the installed components.
Closed-Loop cooling seals the electrical enclosure from hostile elements in the environment. Two separate
circulation systems are employed. The internal system cools and dehumidifies the air inside the cabinet,
totally isolating the sensitive electronics and other components from the environment. The external system
uses circulating ambient air or water to discharge the heat removed from the electronics.The heat is dissipated
from the enclosure by means of the vapor compression refrigeration cycle. This takes place in a hermetically-
sealed refrigeration system, utilizing either an air-cooled or water-cooled condenser heat exchanger. The warm
air inside the enclosure is drawn through the evaporator coil where it is cooled, dehumidified and returned.
Any enclosure moisture accumulated on the evaporator coil is collected in the condensate tray and released to
the ambient air through the drain tube or the condensate evaporator.
The heat removed through the evaporator coil is transferred by the compressed refrigerant to the condenser
coil. Ambient air or water is then passed through the condenser coil, where it absorbs the heat and is then
discharged to the environment.
Kooltronic Air Conditioners are designed to operate continuously in order to eliminate compressor cycling,
which shortens compressor life and causes line transients. The cool air discharge temperature is regulated by
the capacity control (hot gas bypass) valve. The unit is equipped with a Low Temperature Thermostat to prevent
over-cooling. In applications having frequent voluntary or involuntary power interruptions, an optional
Compressor Short Cycle Protector is recommended to allow adequate time for the internal pressures of the Air
Conditioner to equalize before restarting.
V. Principles of Operation
CONDENSER OUTLET
(Heated Ambient Air Out)
CONDENSER HEAT
EXCHANGER
CONDENSER AIR
INLET
(Ambient Air In)
REFRIGERANT
FILTER DRIER
CONTROL
BYPASS VALVE
METERING
DEVICE
(Capillary Tube
shown)
COMPRESSOR
EVAPORATOR
HEAT EXCHANGER
COOL AIR TO
ENCLOSURE
ACCUMULATOR
CONDENSER
AIR INLET
(Ambient Air In)
HEATED AIR FROM
ENCLOSURE