DFRIGO User Manual |
Document subject to change without prior notice.
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General description of the unit.
5.1
Introduction
Our humidifiers are designed to operate uniformly and continuously, to be easy to install and
require minimal maintenance. The high-performance silica gel drying rotor extracts the
humidity from the air treated by adsorbing the water vapour molecules, which means that it
behaves consistently even in conditions of low humidity.
Synthesized silica gel is a material that is stable both chemically and thermally, so it does not
result in deliquescence (the process whereby a substance absorbs moisture from the
atmosphere), unlike other desiccant materials. This means that it behaves and performs
consistently and therefore our products have long working lives.
It
’s chemical resistance, together with the fact that it is water-washable, contributes to it’s
durability. Standard units can achieve dew point values of up to -25ºC for treated air humidity.
5.2 Operating Principle
The straightforward operation of our DFRIGO series of dehumidifiers consists of two
continuous and simultaneous airflows running in opposite directions through the desiccant
rotor, and, in the case of the DFRIGO-ECO series, also through a heat-exchanger plate.
A flow of air to be dried (process air) and a fan reactivation flow (moist air).
Having been filtered, the process air passes through the desiccant rotor, shedding most of
the water it contains; it is then extracted from the dehumidifier by a ventilator fan as dry air
(in the case of DFRIGO-ECO models, this dry air passes through the heat exchanger plate
to shed the sensible heat gained on the rotor) and driven to the system or zone to be treated.
In DFRIGO-ECO models the heat exchanger plate enables the process to be isenthalpic.
In DFRIGO-HPR models the flow exchanger enables air from outside to be used for
reactivation.
The reactivation air from the rotor is drawn in from outside, filtered, pre-heated in the heat
exchanger plate (only in DFRIGO-ECO models) and post-heated by a heater that uses
electrical resistance.
Once it has reached the temperature necessary to convey the water vapour retained by the
desiccant rotor, a fan extracts this moist air from the dehumidifier to be expelled to the
exterior.
