Nothing beats cross, natural ventilation from open doors and windows or the use of fans, to cool your home. Only install an air conditioner if it is absolutely necessary.

The performance of air conditioners is measured by its COP (sometimes CP) which is the ratio of the heating or cooling provided over the electrical energy consumed. These days there are very highly efficient air-conditioners available.

If you have an old technology ‘room’ air-conditioner in your home, consider replacing it with modern inverter technology to optimise energy savings. All air-conditioning systems need to be properly maintained to ensure energy efficiency.

There are two types of air-conditioners:

  • Room air-conditioners cool a single room rather than the entire home. These traditionally feature a one way cassette and are wall mounted
  • Central air conditioners circulate cool air through a system of supply and return ducts. They can either be split-system where an outdoor cabinet contains the condenser and compressor, and an indoor cabinet contains the evaporator or a central system, where the air conditioner, the evaporator, condenser, and compressor are all located in one cabinet, which usually is placed on a roof or on a concrete slab next to the house’s foundation. Ideally in a central system, a variable capacity compressor linked to multiple indoor units should offer each unit their own individual temperature control.

What you need to know

  • There are over 50 different air-conditioning suppliers in South Africa. Choose wisely, preferably a well-known brand which offers high energy efficiency importance
  • Use ambient air to cool your building down at the start of the day by only turning on your air-conditioner fan.
  • A centrally positioned 4 way cassette system, which distributes air in all directions, will offer better energy efficiency than a wall mounted single cassette
  • It is advisable that the difference between the inside and outside temperatures should not exceed 10 degrees Celsius. Adjust your air-conditioner settings accordingly for substantial savings
  • It is not energy efficient to maintain a cool interior long after the people who needed it, have gone. Program operational time according to the demand required. Switch off when not in use
  • Your home can be used to “store” coolness. By shading a home from the outside by means of trees, horizontal metal blinds, awnings or heat reflecting film on windows, direct sunlight is prevented from heating the interior.
  • Ceiling insulation is one of the most effective ways of beating the heat. Proper insulation slows the process down of heat entering a house through the roof, while in winter preventing hot air from escaping through the roof.
  • Air moving over a pool or pond provides a natural cooling effect for a home. Consider breeze patterns and the strategic positioning of your pool or water feature when designing your home.
  • Appliances and equipment, such as kettles, computers, copiers and lights give off heat while in operation. Therefore, switching them off when they are not in use would further cool down the temperature inside a room or building.
  • Ducts must be sealed and well insulated to ensure optimal performance
  • In terms of the new SANS 204 regulations, cooling and heating equipment shall have efficiencies in accordance with ASHRAE 90.1. (American Society of Heating, Refrigerating and Air Conditioning Engineers)
  • Service and commissioning your air conditioner or air conditioning system will ensure optimal performance

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