Rittal LCU DX
9
3 Device description
EN
on fixing brackets on the rear wall of the evaporator coil.
The evaporator coil has two condensate collecting trays
to enable installation on the left or right of the enclosure.
The bottom condensate discharge in each case remains
unused.
The internal unit is comprised of the following compo-
nents:
– Housing of powder-coated sheet steel.
– Two condensate collecting trays in the enclosure (bot-
tom/top) so that the evaporator coil can be used in
two installation positions. The discharge connection of
the condensate tray has a diameter of 12 mm.
– Direct refrigerant evaporator coil of inner-grooved
copper core pipes with aluminium membranes. The
evaporator coil is pressurised with exhaust air from the
server in order to ensure heat absorption (heat dissi-
pation) via the refrigerant flowing into the copper
pipes.
– Evaporator coil fan as linear controlled EC fan.
– Full electronic control of all components in the internal
unit, for evaporator coil fan speed control, server in-
take air temperature control, and power demand from
the external unit. The controller has temperature sen-
sors built into the intake and exhaust side of the inter-
nal unit, as well as on the evaporator coil itself.
– Additional temperature sensor in the server front.
3.3.2
External unit (inverter-controlled cooling
unit)
The external unit is comprised of the following compo-
nents:
– Housing of weather-proof, stove-enamelled sheet
steel.
– Compressor for compressing and circulating the re-
frigerant from the low-pressure side (internal unit) to
the high-pressure side (external unit). The motor is ac-
tivated by an external inverter, which controls the
speed of the compressor and therefore allows the
cooling output to be precisely adapted to the actual
cooling requirement.
– Full electronic control of all components and measure-
ment devices on the external unit, including various
sensors and pressure measuring devices.
– Condenser for condensing the compressed refriger-
ant so that it can be returned to the evaporator coil via
the expansion valve in liquid form. The condenser is
comprised of copper core pipes with aluminium mem-
branes and a DC fan motor, which is speed-controlled
to adjust the output.
– Electronic expansion valve to supply the evaporator
coil with the required volume of refrigerant, so as to
ensure the corresponding optimum thermal absorp-
tion capacity to suit the current output requirements.
The expansion valve is electronically regulated via the
pilot wire from the evaporator coil.
3.3.3
Refrigerant lines and electrical pilot wires
The medium connection lines between the internal unit
and the external unit are comprised of the following
components:
– Pair of refrigerant lines as a refrigerant suction line (re-
turn) and refrigerant liquid line (inlet), including conden-
sate insulation. Refrigerator-quality copper pipes
should be cleaned and dried (to DIN EN 12735-1/DIN
1786) and sealed before use.
– Electrical and pilot wire lines between the internal unit
and the external unit in a UV-resistant design.
3.4
Proper and improper usage
The LCU DX is used to dissipate low to medium heat
losses and for the effective cooling of devices built into a
server enclosure/Micro Data Center. The unit is de-
signed solely for static use in sealed rooms.
The unit is state of the art and built according to recog-
nised safety regulations. Nevertheless, improper use
can pose a threat to the life and limb of the user or third
parties, or result in possible damage to the system and
other property.
Consequently, the unit must only be used properly and
in a technically sound condition!
Any malfunctions which impair safety should be rectified
immediately.
Proper usage also includes following the operating in-
structions and fulfilling the inspection and maintenance
conditions.
Inappropriate use can be dangerous. Examples of inap-
propriate use include:
– Use of another external unit
– Improper operation
– Use of a refrigerant other than R410A
– Use of a refrigerant fill volume other than that specified
– Installation of the external unit in an unsuitable position
– Improper rectification of malfunctions
– Use of replacement parts which are not authorised by
Rittal GmbH & Co. KG
– Non-static use, e.g. on moving or vibrating machines
