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12.2.6 - Units with variable operating pressure fans (Option
12)
Ductable units are intended to be ducted on the fan discharge,
and can be installed inside a machine room.
For this type of installation, the cold air produced by the air-
cooled exchangers is evacuated from the building by the fans
by means of a ductwork system, which causes pressure drops
in the air circuit.
Installing a ductwork system on the fan discharge generated
a pressure drop due to the air flow resistance.
The intake air can be recovered either inside or outside the
room.
For each installation, the duct pressure drops differ, depending
on the duct length, the duct section and the direction changes.
Therefore, more powerful fan motors are installed in this
option than on the standard units.
Ductable units equipped with this option are designed to
operate with ducts whose air evacuation generates a maximum
pressure drop of 200 Pa.
Using a speed variation up to 19 rps enables the system to
overcome the pressure drops in the ducts while maintaining
an optimised air flow in each circuit.
All the fans in the same circuit run at the same time at the
same speed.
In cooling mode, the full-load or part-load speed is controlled
by a patented algorithm that permanently optimises the
condensing temperature to ensure the best unit energy
efficiency (EER) whatever the operating conditions and
pressure drop of the system ductwork.
If required by a specific installation, the unit's maximum fan
speed can be configured in the Service Configuration menu.
Refer to the control manual.
The performances (capacity, efficiency, noise level) depend on
the fan speed and the ductwork. Please refer to the
manufacturer's electronic catalogue to evaluate the estimated
impact of the duct system on the unit's operating conditions.
12.2.6.1 - Specific installation on ductable units
Ductable units must be installed on a waterproof base enabling
efficient drainage and evacuation of the condensate from the
heat exchangers.
The rotation speed of all the fans in the same circuit is
controlled in the same way.
Therefore each circuit operates independently.
Each refrigerant circuit must have an independent ductwork
system so as to prevent any air recycling between the air-cooled
exchangers of different refrigerant circuits.
On ductable units, each fan is equipped with a factory-fitted
connection interface frame providing a link between the
ductwork itself and the refrigerating circuit to which the fan
belongs.
Refer to the dimensional plans of the units for the precise
dimensions of this connection interface.
Please refer to the "Fan arrangement" paragraph to allocate
each fan to its own circuit.
12.2.6.2 - Nominal and maximum air flow rate per circuit and per
unit type
30RBP
Circuit A
Circuit B
Nominal/maximum air flow
rate (l/s)
Nominal/maximum air flow
rate (l/s)
160
5200 / 6240
10400 / 12480
180-230
10400 / 12480
10400 / 12480
240-270
10400 / 12480
15600 / 18720
310-330
15600 / 18720
15600 / 18720
380
15600 / 18720
20800 / 24960
430-520
20800 / 24960
20800 / 24960
12.2.6.3 - Air connection on discharge
Refer to the dimensional plans of the units for the precise
dimensions of the connection interface.
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