3. DESCRIPTION OF THE MACHINE
How Dehumidifiers Work
This dehumidifier is called a refrigerant dehumidifier. It is capable of lowering humidity down to as little as 35% relative
humidity (rh).
This action of lowering the humidity is achieved by damp moisture-laden air (referred to as vapour) being drawn through
the dehumidifier by a quiet, powerful fan. The dehumidifying process turns this water vapour into liquid which is then
either collected in a tank or drained away via a hose.
This happens when the incoming vapour is drawn by the fan over cold refrigerated coils. These coils are chilled down
by the compressor. This cools the damp vapour and water droplets form on the cold coils. These water droplets begin
collecting in a water collection tray. Next the cold air passes through a warm heat exchanger which slightly heats up the
air and returns it to the room via an outlet, as clean, dry, slightly warm air.
Simply put, vapour is removed from the room and turned into a solid form, water. This water is then collected and
drained away.
With reference to the drawing (fig. 1), the air is drawn in through the rear side of the dehumidifier, then it passes through
the filter (1), through the aluminium refrigerated coil or evaporator (2), again through the heat- exchanger or condenser
(3). Finally, the fan motor (4) expels the air back into the room through the front grill panel: The condensed water is
collected in the tank (5). A micro-switch (6) stops the machine when the water in the tank reaches the correct level by
raising the water float lever. The humidistat (7) starts the functioning of the dehumidifier when the humidity is higher than
the preset level. An electronic circuit (8) controls the defrosting function and prevents the compressor from excessive
starting.
Some models have a different water tank stop device and use a gravity system (fig. 2) instead of the floating ball.
Fig. 3 refers to the machine with lifting pump, which includes a water collection tank (5) and a floating ball stopping
device for full tank (6).
.
Machines provided with Hot Gas Defrosting System
The models with hot gas defrosting system have one by-pass solenoid valve and a special electronic card.
The functioning of Hot Gas Defrosting is an exclusive Fral system for the dehumidifiers: this system consists of a
thermostat and one electronic control, which use the hot gas by-pass system only when it is necessary and for the period
of time required; this will lengthen the life of the machine by reducing the hot gas functioning phases.
.
Fig. 1
Machines with water
tank floating ball stop
Fig. 2
Machines with water
tank gravity stop
Fig. 3
Machines with condensed
water lifting pump
