Cassette air conditioning is, in fact, one of the “cleverest” forms of air conditioning insofar as ceiling mounted cassettes – mounted in a ceiling void so that only a fascia flush with the existing ceiling is visible – do not compromise wall or floor space but, nevertheless, allows optimum air flow in four different directions. Cassette air conditioning units feature an internal block – typically 600mm x 600mm, or so, in surface area – which is installed into a hung or suspended ceiling. The internal unit incorporates a cooling element, or coil, containing a refrigerant which cools and dehumidifies warm air from a room. The refrigerant carries heat away to a “condenser” and “compressor” unit – located outside the building – and conditioned air is circulated back into the room. Advanced fan technology and directional flaps allow air to be distributed around a room in 2, 3, or 4 different directions so a single cassette – provided that it is sufficiently powerful – can be used to condition the air in a fairly large room or area. Cassette air conditioning systems do, of course, require proper professional installation. The internal units and external unit must be connected by lengths of copper pipe to carry refrigerant liquid or gas so holes – of 3″ or so in diameter – must be drilled through external walls in order to accommodate these. Installation of these systems – depending upon the number of internal units to be installed, building materials, etc. – can quickly become costly in comparison to other air conditioning systems. Running costs, too, can become high if an inappropriate unit is chosen or a unit is positioned incorrectly. Expert advice from a properly qualified engineer or contractor may therefore be necessary even before you choose your cassette air conditioning system.