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 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 an air-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 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 RP17 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.
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
V. Principles of Operation
