Dantherm DFC-350-230V-C3-W-FG, Service Manual

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General principle for DFC units
General A DFC (Displacement Free Cooling) unit supplies the cold outdoor air through a diffu-
sor filter with very low velocity. This will make a dune of cold air at the floor and up to a
height of 1,6 meter in the shelter. The temperature at the ceiling will be relatively high.
The idea is to remove more heat with lower air volume in order to save power con-
sumption of the fan.
This is only possible if a large temperature difference between supply air and air out of
the shelter can be achieved.
Efficiency The efficiency of the DFC unit depends very much on the circulation of the internal air
circulation in the telecom equipment and in the shelter. It is therefore very necessary to
do a thorough test of the airflows in the shelter before initiating a bigger roll out.
Illustration The illustration below shows the DFC and some external parts unit mounted in a con-
tainer:
Parts
This table describes the different part (from right to left) in the illustration above:
Part Description
Outdoor Temp sensor Measures the outdoor temperature (NTC resistor)
DFC unit The unit including bag filter and air inlet hood with com-
pact filter
Controller Climate unit controller CC3000 or other
Heater External electrical heater
Supply 48V DC/230 V AC Supply to the DFC
Room sensor GT1
Measures the indoor temperature (NTC resistor)
Active cooling unit Existing airconditioner (often split unit)
Damper Electrical damper allowing warm air to leave the shelter
Continued overleaf