We use a split system for a range of reasons:

  • Weight; our largest collector weighs only ~110kg on the roof full of water vs. half a tonne of an on roof system.
  • Temperature control/reduce water wastage; with a split system, the temperature in the tank is controlled via a controller – so once it is up to its maximum temperature it will not bring any more heat down, in an on-roof system the “max temperature” safety is usually hot water dumping onto the roof.
  • Aesthetically, most people say the split systems look much nicer on the roof