5.3.1 Top Connection
A soft pipe has been pre-installed between the humidifier and the humidifier supply copper pipe. The top end of the
humidifier supply copper pipe is located on the top plate. If water is supplied from the top of the unit, connect the top end of
the humidifier supply copper pipe (Humidifier Supply on top plate) to your water supply system.
5.3.2 Bottom Connection
If water is supplied to the humidifier from the bottom of the unit, open the front door, unscrew the connector between the soft
pipe and the humidifier supply copper pipe, and route the soft pipe through the Humidifier Supply on the base plate to your
water supply system.
NOTE: The end of the humidifier supply pipe is G3/4 connector. You can use the convertor provided in the
accessories bag to convert the connector to Rc1/2.
5.4 Connecting Gas Pipe and Liquid Pipe
WARNING! The operation of opening the valves and cutting the pipes at the bottom of the unit must be
carried out as final operations.
Note the following while connecting gas pipe and liquid pipe:
•
Connect the condenser and evaporator using copper pipes.
•
Use as short refrigeration pipelines as possible to minimize the total charge of refrigerant and the pressure
drops.
•
Reduce the number of bends to a minimum. The bend must be of large radius, at least equal to pipe diameter.
If not using preformed curves, bend the pipes as follows:
Soft copper: by hand or bending device.
Hard copper: use preformed curves. Do not overheat the pipes when brazing so as to minimize oxidation.
•
Lay the horizontal gas pipes with 1% downward gradient in the direction of the refrigerant flow.
•
Maintain a minimum distance of 20 mm (0.8 in.) between the gas and liquid pipelines. If this is not possible,
insulate both lines.
•
Insulate the piping to avoid damage to cable, if the pipes are put next to electrical cables.
•
Support both horizontal and vertical pipes with vibration damping clamps (including rubber gaskets). It is
recommended to place clamps every 1.5 m to 2 m (4.9 ft to 6.6 ft).
•
When the condenser is installed higher than the compressor: install an inverted trap to the discharge line of the
evaporator and the liquid line of the condenser. The inverted trap prevents the liquid refrigerant from flowing
back when the condenser stops working. The top end of the inverted trap must be higher than the height of the
copper pipes of the condenser. The minimum height difference is 150 mm (5.9 in.).
•
Install an oil trap every 7.5 m (24.6 ft) of the vertical discharge line.
NOTE: Equivalent pipe length = Length of straight pipe + Equivalent length of bend
5 Piping and Refrigeration Connections
38
Vertiv™ Liebert® CRV CRD25 and CRD35 Row-Based Cooling System User Manual
