fisair DFRA Series, User Manual

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User Manual DFRA Series |
32
9.3 Air ducts
In general, the equipment installer knows the sizing and layout process for air transport
ducts for any type of air conditioning, and that process is applicable to a dehumidifier.
However, the following points are important:
- Ensure that the pressure available to the fans has been considered when
designing the correct size of the ducts, so the equipment can operate at nominal
flow rates.
-
The equipment has control dampers in the suction of both air circuits, for isolation
during inactivity and to adjust the available fan pressure.
-
The outside air intake must be protected (by grids or mesh) to protect against
entry of foreign matter, e.g. leaves, insects and rainwater.
-
The external air intake and the wet air outlet must be kept separate (minimum
3m) so as not to affect the equipment performance.
- Provision must be made for the removal of any cooled condensation produced in
the wet air duct during operation. This can be achieved by ensuring a downward
inclination towards the outside, for horizontal ductwork. Ensure that upward
slopes are adequately insulated or drill a hole larger than 5mm at the lowest point
to remove any condensation. This prevents it returning to the unit or restricting
airflow inside the duct.
IN HORIZONTAL DUCT RUN :
SLOPE DOWN AWAY FROM THE
OUTLET TO REMOVE THE
CONDENSATION
IN VERTICAL DUCT RUN:
INSTALL A DRAIN (HOLE)
AT THE LOWEST POINT TO
REMOVE CONDENSATION
INSULATED
DUCT AVOIDS
CONDENSATION
PROCESS
AIR
DRY AIR
WET AIR
OUTLET
MINIMUM
GAP 3 M
REACTIVATION
AIR INTAKE