Dantherm CDF 40, Service Manual

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Product description: Overall description
Product description
Overall description
This illustrates the functional principle of the CDF 40-50-70.
CDF
Fig. 1
CDF 40-50-70 work in accordance with the condensation principle.
Humid air from the room is drawn into the unit by one or two fans.
When passing through the evaporator the air is cooled down to below dew point and water
vapour is condensed into water, which is drained.
The dry air is then passed through the condenser where it is heated and returned to the
room. As a result of the latent heat from the condensation process and the compressor en-
ergy the return air temperature to the room is approx. 5ºC higher than the air from the room.
When the dehumidifier is started by the hygrostat, the fan(s) are activated at the same time as
the compressor.
To protect the compressor against overloading there is a timer which prevents the dehu-
midifier from starting more than 10 times pr hour. It means, that there is at least 6 minutes
between every start up.
This unit is equipped with an intelligent defrosting strategy.
The unit monitors the temperature of the evaporator, and when the temperature has been
below a certain temperature for a period of time, the dehumidifier will switch to active
defrosting, the fans will stop, and the magnetic valve will open.
The hot gas can now pass through the evaporator.
When the evaporator has the right temperature again the magnet valve will close and the
dehumidification will continue.
If the temperature in the dehumidifier increases to a temperature of more than 55 °C (in case
of fan failure or room air temperature higher than 36 °C), the compressor stops automatically
to avoid damaging it. When the temperature allows it the dehumidification will continue.
Air flow direction
Functionality of
the dehumidifier
Fan control
Compressor
control
Defrosting
Safety circuit