This unit is often used in domestic applications and server rooms. The wall unit is the quickest to install and the cheapest to buy. So ultimately that means the lowest installed price. The unit is hung on a wall above head height and blows hot or cold air into a room from one louvre.

This unit is used when there is no ceiling void or no wall space. It is slightly more expensive to buy than a wall unit but takes about as long to install. It is a little like a radiator except it blows hot or cold air rather than using water.

This unit is often used in offices. The cassette unit is fixed from the roof above a ceiling void and the white four way fascia is the only part of the unit you see. It takes longer to install this unit than a wall mounted and is more expensive to buy but it distributes the air in four directions so gives better coverage and a more gentle air flow.

This unit is the "crème de la crème" or the "Rolls Royce" of air conditioning! It is, of course, the most expensive to buy and install but it means the customer sees nothing other than inconspicuous air diffusers in the ceiling. The unit is mounted, as the cassette, above a ceiling and ductwork is installed to carry the air to the diffusers. This gives a very comfortable environment and good coverage.