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Subject to change without notice DHA 250
Installation
Installation and service access
Dehumidifier DHA 250 is designed for
indoor installation. The dehumidifier should be
installed horizontally.
All components in the dehumidifier are acces-
sible from the top of the unit. For inspection
and service, a space of 400 mm must be left
free above the dehumidifier to accommodate for
servicing of filter, fan and rotor.
When using a mounting plate, the dehumidifier
must be put so that the rotorshaft still is horizon-
tal and the wet air outlet is placed low.
Duct connection for permanent
installation
The dehumidifier can be installed in the room
that should be dehumidified or in a separate
plant room.
To obtain the best performance the outlets from
the fans should be equipped with diffusors.
Wet air duct out from dehumidifier
The wet air from the dehumidifier should be
exhausted to the outside. The duct should be as
short as possible to minimise the chance of con-
densation of the wet air. This duct should slope
down slightly to stop any condensed water from
flowing back into the dehumidifier.
If the wet air duct is extremely long, or must be
installed sloping upwards from the dehumidifier,
it should be insulated and have a drainage point
(2 mm) drilled at its lowest position.
A damper should be installed in the wet air duct
to enable correct setting of the reactivation air
volume during commissioning.
The exhaust opening should have a coarse wire
net.
Reactivation air into the dehumidifier
For reactivation of the dehumidifier an addi-
tional air volume is needed. This air enters the
unit along side the process air. As an option the
dehumidifier can be equipped with duct connec-
tions for entering air (2 x Ø80). One of them can
be used for intake of ambient air for reactivation.
The duct should be as short as possible, requires
no insulation, and can slope up or down. In some
installations, as an alternative, the reactivation
air can be taken from the installation plant room,
for this alternative no duct connection is needed.
Process and dry air with the dehumidifier
installed in the dehumidified room
When the dehumidifier is installed in the
dehumidified room it would normally take the
process air directly from the room without any
duct system. If the process air inlet needs to be
connected to a duct system, the dehumidifier is
prepared for using a plate with duct connections.
The dry air outlet would normally have a duct
system designed for distribution of the dry air in
the building.
Process and dry air with the dehumidifier
installed outside the dehumidified room
When the dehumidifier is installed in a separate
plant room all inlet and outlet openings are usu-
ally ducted.
The dehumidifier takes the process air as ambi-
ent air, or as pre-treated air (cooled/heated), or
alternatively as return air from the dehumidified
room. The dry air from the dehumidifier can be
connected for post treatment or ducted back to
the dehumidified room.
Dampers should be installed in the dry and wet
air ducts, enabling correct commissioning of the
air volumes.
