Installation and Maintenance Manual

Operating Principals
RTAE-SVX001B-EN 41
provide variable speed fan control for all fans and are
designed with permanently lubricated ball bearings,
internal temperature and current overload protection, and
fault feedback as a standard product offering. The fan
impeller is a nine bladed-shrouded fan made from heavy-
duty molded plastic. Standard units will start and operate
between 32 to 105°F (0 to 40°C) ambient.
The UC800 controls calculate optimum fan speed for
maximum efficiency based on compressor load and
outdoor air, resulting in high IPLV values.
Evaporator
The evaporator is a tube-in-shell heat exchanger design
constructed from carbon steel shells and tubesheets with
internally and externally finned seamless copper tubes
mechanically expanded into the tube sheets.The
evaporator is designed, tested and stamped in accordance
with the ASME Boiler and Pressure Vessel Code for a
refrigerant side working pressure of 200 psig.The
evaporator is designed for a water side working pressure
of 150 psig. Standard water connections are grooved for
Victaulic style pipe couplings, with flange style
connections optionally available. Waterboxes are
available in 2 and 3 pass configurations and include a vent,
a drain and fittings for temperature control sensors.
Evaporators are insulated with 3/4 inch closed cell
insulation. Evaporator water heaters with thermostat are
provided to help protect the evaporator from freezing at
ambient temperatures down to -20°F (-29°C). A factory
installed flow switch is installed on the supply water box in
the evaporator inlet connection.
Drive Cooling System
Each refrigeration circuit has a compressor drive cooling
circuit. Each drive cooling circuit includes a wet rotor
circulation pump that circulates a secondary heat transfer
fluid in a closed system between the adaptive frequency
drive components between the heat sinks of the adaptive
frequency drive and a brazed plate heat exchanger.The
pump is fed from a thermal expansion tank with a vented-
pressure cap which is also used as the circuit pressure
relief.The circuit also includes a particulate strainer and a
drain valve for servicing.