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 electronics 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 and evaporated
in the condensate evaporator tray and released to the ambient air by the condenser blower.
If latent heat exceeds 25% of the total cooling capacity excess condensate is released to
the ambient through the drain tube.
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.
The unit is equipped with a Low Temperature Thermostat to prevent the evaporator coil
from freezing and must not be set below factory setting of 75°F (16°F differential). If
necessary the thermostat may be adjusted to increase the temperature within the cabinet.
Unlike thermostats that are commonly found in household air conditioners that control
the room temperature, the thermostat found on the RP47 monitors the return air from
the enclosure to prevent the evaporator from freezing. In conditions of low ambient
temperature and low enclosure load, the thermostat regulates the return air temperature
from 75°F to 91°F. If the unit is equipped with an optional non-adjustable high temperature
alarm, it will activate when the return air teperature reaches 130°F.
V. Principles of Operation
CONDENSER OUTLET
(Heated Ambient Air Out)
CONDENSER HEAT
EXCHANGER
REFRIGERANT
FILTER DRIER
COMPRESSOR
EVAPORATOR
HEAT EXCHANGER
COOL AIR TO
ENCLOSURE
ACCUMULATOR
CONDENSER
AIR INLET
(Ambient Air In)
HEATED AIR FROM
ENCLOSURE
M/TAB
CONDENSATE
EVAPORATOR TRAY
