What is a Heat Pump Hot Water System?

As technology advances and continues to develop, households have access to more and more products that increase efficiency and reduce carbon footprints. One such technology is heat pump hot water systems.

Heat pump hot water systems are ideally suited to warm, sunny regions where they extract heat from the air around them (which can include the heat the ground absorbs from the sun during the day) and amplifies it using a refrigerated system.

What is a heat pump hot water system?

A heat pump is a household water heater that can be connected to your existing electric hot water piping. It uses a liquid chemical that is ozone friendly and boils at incredibly low temperatures. Rather than using lots of electricity to heat a water tank, it uses warm air as a heat exchange for its insulated storage cylinder.

By extracting heat from the surrounding air and using it in a cost-effective and environmentally friendly way, it allows people living in warm climates to utilise the air outside to create warm water on repeat and cut down on their electricity costs.

How do heat pump systems work?

Heat pump technology is very similar to a refrigerator, only in reverse. Once your heat pump hot water system has been professionally installed, it will extract heat from the air surrounding it and use it to “boil” a liquid chemical inside, in doing so the liquid turns to gas. Because the liquid inside is naturally very cold, any air from outside is warm enough to cause the evaporation process.

Once in gas form, electricity is engaged to activate a compressor to put pressure on the gas to drastically increase the heat. When the temperature climbs, the heat from the pipes holding the chemical is transferred into the tank of water. As the water heats, the pipes are cooled, returning the refrigerant chemical to liquid ready for the next time heating is required.

The pros & cons of owning a heat pump

Before you make your purchase it’s important to factor in all the benefits and drawbacks so that you can make an informed decision on what will work for you.


  • Government rebates are available in some cases to help with costs
  • Drastically reduced energy bills
  • Significant reduction of your carbon emissions
  • You’ll get plenty of choice with around 18 brands and 80 separate models to choose from


  • There’s a higher upfront price for the unit compared to other hot water systems (as much as double) which puts it out of budget for some, although you can usually earn this back in what you save in energy costs.
  • There needs to be adequate space surrounding the unit and it needs to be installed in a well-ventilated area – which won’t be a great fit for people who currently have an interior hot water system in a small cupboard space.
  • The compressor can be noisy so needs to be placed away from bedrooms and neighbours.
  • When used in low-temperature climates it can put a strain on the compressor, reducing its lifespan and increasing maintenance costs.

Hot water use makes up a large portion of Australian household electricity bills, in fact, it’s second only to space heating and cooling. Heat pumps are an exciting innovation as they can save as much as 60-70% on your current power consumption, every bill, every year for the next 15 years or more.  A good plumber can help you decide which types of hot water systems are best for you and provide quality installation no matter what your personal choice is.