How do air conditioners work

There is a wide range of air conditioning equipment, suited to differing needs, but the basic underlying principle is generally the same. A typical ducted system, comprising of an indoor section and an outdoor section, illustrated below, works as follows:

1. Stale air is continually extracted from the room at a pre-selected rate through a return air grille.
2. Fresh air can be added to this returning air if required.
3. The mixture of fresh and return air is filtered to remove any dust particles.
4. The filtered air is passed over a cooling coil, which not only lowers the air temperature to a pre-set level, but also removes moisture from the air. This moisture removal is referred to as De-humidification.
5. The coil is cooled by a refrigeration unit - more commonly referred to as the Condensing unit, which is sited outside the building. From here the heat content from our conditioned room is dissipated into.
6. If cooling is not required, normally there Is no separate need to de- humidify. If heating is required instead, a heater battery normally provides this. The heater may be electric, hot water or reverse cycle heat pump.

Heat Pumps
Most of todays air conditioning systems are Heat Pumps. They are able to provide cooling and de-humidification in the summer, heating in the winter and air filtration all year round. How the heat pump provides Its heat is quite simple - the refrigerant flow in the two pipes that connect the indoor unit and the outdoor unit is reversed. This enables heat to be taken from the outdoor air and then combined with the heat from the condensing unit compressor, to provide some if not all of the rooms heating requirement.

Did you know that for every unit of electricity consumed to drive the heat pump, some 2 to 2.5 units of useful heat energy are made available for heating use.

This means that energy consumption for heating can be substantially reduced.