The Grant Aerona ³ is a AAA rated air source heat pump, meaning its one of the most efficient units on the market today, and the purpose of this video to show you how to run this appliance at its most efficient. What helps all heat pumps maximise their efficiency is down to a number of points -The quality of the building in terms of insulation and air tightness -Understanding how best to use the heating controls -Ensuring the appliance is serviced annually