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QEWR002G ©STULZ USA – All rights reserved
CYBERROW DX ENGINEERING MANUAL
PRODUCT
GUIDE SPE
CIFIC
A
TIONS
modulation of the unit’s cooling capacity, and evaporator coil
freeze protection under low load conditions.
PIPING CONFIGURATION
Top Piping:
When top piping is specifi ed, the CyberRow units
shall be provided with connections for water/glycol or refrigerant
piping and condensate discharge on the top of the cabinet.
Bottom Piping:
When bottom piping is specifi ed (e.g. raised
fl oor applications), the CyberRow units shall be provided
with connections for water/glycol or refrigerant piping and
condensate pump discharge through the bottom of the cabinet.
CONDENSATE PUMP
The CyberRow shall include a factory wired and installed
condensate pump. The condensate pump shall have the capacity
of 80 gal/hr. at 23 ft. of lift with a maximum shut off (head) of
115 ft. The condensate pump shall be piped with either top or
bottom discharge connections, to remain consistent with top or
bottom piping connections.
RETURN AIR SENSOR
A factory mounted and wired temperature sensor (NTC) mounted
in the return air stream temperatures shall be provided.
SUPPLY AIR CONTROL (OPTIONAL)
The STULZ CyberRow shall be provided with a temperature and
humidity sensor factory unit mounted in the return air stream and
a fi eld installed supply air temperature (optional) and humidity
sensor for supply air temp control capabilities. The controller
shall provide the user an adjustable supply air control setpoint.
AIR COOLED HEAT REJECTION
-20°F Variable Fan Speed Control (AR)
The air cooled system shall incorporate a low ambient, variable
speed fan, head pressure control. The pressure control shall be
for year-round air conditioning system operation down to -20°F
DB minimum ambient air temperature.
-30°F Flooded Control (AR)
The air cooled system shall incorporate a low ambient, fl ooded
head, pressure control. The pressure control shall be for year-
REFRIGERATION SYSTEM
All piping and components contained within the
refrigeration system shall be rated for use with R410A
refrigerant. Each refrigeration circuit shall include, as
a minimum a refrigerant drier/strainer, sight glass with
moisture detector, an electronic thermal expansion
valve, an evaporator coil, a compressor, a high pressure
switch with manual reset, and a low pressure switch with
automatic reset.
FIXED SPEED SCROLL COMPRESSOR
The compressor shall be a high effi ciency, high reliability
and low noise scroll compressor.
The compressor shall be equipped with internal line
break motor protectors, an internal pressure relief valve
and external vibration mounting isolation.
VARIABLE SPEED COMPRESSOR
(CRS-090)
The speed of the compressor shall be controlled with
a variable frequency drive (VFD) to match compressor
capacity to the actual thermal load. The VFD shall be
capable of providing power for the compressor to operate
up to 120rpm. The VFD shall proportionally control the
compressor motor speed to maintain a constant supply
air temperature.
EVAPORATOR COIL
The evaporator coil shall be constructed of seamless
drawn copper tubes, mechanically bonded to tempered
aluminum fi ns (that have an enhanced design for
maximum heat transfer), and mounted in a stainless steel
condensate drain pan. The coil shall be designed for a
maximum of 500 ft./min. face velocity.
PROPORTIONAL ELECTRONIC
EXPANSION VALVE
An electronically operated thermostatic expansion valve
shall be installed to precisely control the fl ow of liquid
refrigerant into the evaporator coil while maintaining
the desired superheat across a wide range of operating
conditions.
ELECTRONIC HOT GAS BYPASS
(CRS-042/084)
An electronically operated hot gas bypass valve shall
be installed. The hot gas bypass valve shall provide