Technical information

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13.2.- Enthalpy sensors for economiser
Applicable when requiring an economiser control system
that adapts best to the areas in which the humidity level is
important.
13.3.- Barometric relief damper
To relieve excess air pressure that can be generated within
the building when an economiser or motor-driven damper
is used. It is the most economic and adequate extraction
system for installations in which return air is not ducted and
an extraction of a maximum of 25% of the total impulse air
flow is expected.
It comprises a surge pressure damper located at the return
of the unit. Includes a rain hood with a grid for protection
against birds.
When it opens, the entering outdoor air increases and the
return air flow is decreased proportionally, the pressure within
the building rises. When this pressure is greater that the at-
mospheric pressure, the damper opens, releasing excessive
pressure directly outdoors.
When the return duct connection is at the bottom of the unit,
the barometric damper assembly and rain hood are supplied
fully installed on the unit.
If the return duct connection is on the side, it must be installed
at the job site directly on the front surface of the return duct,
as close as possible to the unit (see Fig. 11).
- Fig. 11 -
Economiser with surge pressure barometric damper
OUTDOOR
AIR
EXTRACTION
RETURN
AIR
FULLY
FACTORY
INSTALLED
ACCESSORY
BOTTOM RETURN ASSEMBLY
OUTDOOR
AIR
RETURN
AIR
EXTRACTION
SIDE RETURN DUCT
IN THIS CASE, THE ACCESSORY SHOULD BE INSTALLED ON THE FRONT
OF THE RETURN DUCT. FOR THIS PURPOSE, A FLAT FRONT SURFACE
OF 2000 x 650 mm IS REQUIRED (SEE ACCESSORY INSTALLATION
INSTRUCTIONS)
ATTENTION: INDICATE RETURN AIR DUCT
LOCATION WHEN PLACING THE ORDER