Technical data

/08.2011/CW/32EN
8.3 Air circuit
Heat exchanger (CW-coil)
The heat exchanger consists of copper tubes with aluminium fins. If refrigerant leaks occur, they should be searched
for at the heat exchanger. Beyond that, the heat exchanger is exposed to the air pollution, the particles of which
settle at the fins and reduce the heat transmission the same as raise the air resistance. The latter shows when the
fan current increases.
The heat exchanger can be cleaned by pressurized air which has to be blown opposite to the normal air flow direction
along the fins.
Do not distort the fins while cleaning, this also increases the air resistance !
Fan
The bearings of the fans are lifetime lubricated and do not need maintenance. Check the operation current. An in-
creased operation current indicates either a higher air resistance by a clogged pre-filter or a winding short circuit in
the fan motor.
The fans are speed controlled in dependance of the required cooling capacity. You can manually modify the speed
at the controller for test purposes, so as to compare the measured current with the values on the pages with the
technical data or with those of the planning tool.
Air filter
A filter monitor controls the state of the filter. As soon as the pressure loss exceeds an adjustable value, a filter alarm
via the controller is released. The controller can be configured such as to compensate the pressure loss by a higher
fan speed, however you should not wait too long for exchanging the filter. The filters can be accessed by the front
doors, depending on the cabinet size the number of filter elements varies.
The clogged filter elements can not be cleaned with pressurized air, as the filter structure would be destroyed other-
wise. When you re-install the filter elements after the exchange, take care that the side with the coloured mark (dirt
side) is turned away from the heat exchanger.
8.4 Water circuit
Tightness
Check the water circuit visually for tightness. Beyond that a level indication at the storage tank, if existant, can give
information about changes of the water quantity. A lack of water in the circuit is replaced by air, which reduces the
heat capacity of the chilled water circuit and is detrimental to the pump.
8.5 Unit in general
Electrics
Check the connection terminals for tight fixation when the unit is installed and once again after an operation time of
30 days.
Mechanics
Clean the unit's inside with a vacuum cleaner. Clean pipes simplify the search for leaks. Check the pipes for a tight
seat. Vibrations of pipes and circuit components can result in leaks. Check also the insulation of the water piping.
Condensing air humidity on cold water pipes means a loss of cooling capacity.