Trane CAUJ-C20, Инструкция по установке, эксплуатации и обслуживанию, Страница: 44 / 60

44 CAUJ-SVX01E-EN
Low Ambient Dampers
Low Ambient Dampers are available as a factory
installed option or can be field-installed. Dampers are
used to extend the operation of these units from the
standard operational temperatures to a minimum of
0ºF without hot gas bypass or 10ºF with hot gas bypass.
(These values apply when wind speed across the
condenser coil is less than 5 m.p.h.). If typical wind
speeds are higher than 5 m.p.h., a wind screen around
the unit may be required. By restricting the airflow
across the condenser coils, saturated condensing
temperatures can be maintained as the ambient
temperatures change.
The low ambient damper actuator controls damper
modulation for each refrigerant circuit in response to
saturated condensing temperature.
Low Ambient Thermostats
20 to 60 Ton Units
In addition to the low ambient dampers on 25, 30, 50 &
60 Ton units, a low ambient thermostat is installed to
further restrict the airflow across the condenser by
cycling the 2B3 condenser fan on 25 & 30 Ton units plus
2B6 on 50 & 60 Ton units. The thermostat opens when
the ambient temperature reaches 65ºF and closes at
approximately 67.5ºF.
80 to 120 Ton Units
In addition to the low ambient dampers a two stage
low ambient thermostat is installed to further restrict
the airflow across the condenser by cycling the 4B1 +
4B6, 5B1 + 5B6 on 100 & 120 Ton units. The final stage
thermostats opens when the ambient temperature
approaches 65°F and closes at approximately 73°F. The
second stage opens when the ambient temperature
approaches 45ºF and closes at approximately 53°F.
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