What is a Heat Pump?

So what is a heat pump and how is it an efficient heating system? Are you someone who has heard of heat pumps, but are not exactly sure what they are or how they work?

In most simple terms a heat pump is a device that transfers heat energy. When we are talking specifically about water heat pumps, they transfer heat abundant in the air to heat the water stored in the tank.

The secret to the high efficiency achieved by heat pumps in they are just like in a refrigerator, but running in reverse.

There are several steps in the process:

What is A Heat Pump and How it Works

what is a heat pump
  1. Fresh air flows across an evaporator to enable the abundant heat in the air to be absorbed. The heat pump requires good ventilation around the unit for the evaporator to extract heat effectively.
  2. A fan is used to assist the air flow across the evaporator and remove the cooled air.
  3. A liquid refrigerant passes through the evaporator where it picks up heat from the air changing from a liquid refrigerant to a gas.
  4. The gaseous refrigerant is then compressed by an electric compressor.
  5. Compressing the gaseous refrigerant causes its temperature to rapidly increase becoming much hotter than the water in the tank.
  6. The heated gas now flows into a condenser, where it shifts the heat to the copper coil.The hot copper coil heats the water in the tank.
  7. After passing through the condenser coil, the gaseous refrigerant then flows back through an expansion valve where its temperature drops and it returns to liquid form.

Higher Efficiencies Achieved by Heat Pumps

The most significant difference between a heat pump and other systems used to heat water is that heat pumps use minimal electricity to operate – about 1000 watts (or ten 100 watt light bulbs) – as electricity is only required to run the compressor and a fan. That is less than a quarter of what is required to run an
electric hot water system with electric elements used to heat the water directly.

A heat pump hot water system is highly efficient, saving you money on electricity bills and importantly also being a sustainable system that reduces greenhouse gas emissions.

Learn more about the efficiencies of heat pump systems.

Benefits Over Traditional Solar

A heat pump has similarities to a solar hot water system, but also some major advantages.

Because heat pumps use the heat in the air, they do not require actual sunlight hours, like solar hot water systems do. This means they work on cloudy and overcast days, as well as during the night to draw heat from the surrounding air.

The system is mounted on the ground, removing the need for roof mounting, which can add significantly to the installation costs of solar panel systems, or even make them unworkable (in heavily treed and shaded areas).

More about the differences between solar and heat pump systems.

Need help or advice? Call us today on 1800 420 600 and one of our Heat Pump Specialists will be happy to answer you questions.

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