Air Source Heat Pumps

An air source heat pump (ASHP) can provide your home with both heating and cooling, and it offers an energy efficient and cost-effective alternative to common off-gas heating methods. Installing a heat pump could save you money, earn you money, and will dramatically increase the environmental credentials of your home.

ASHPs use the latent heat in the outside air to heat your home and provide hot water. As air is freely available all around us, air source heat pumps have the advantage of relatively low installation costs and minimal space requirements as they are installed outdoors. Because the source of heat – the air – is abundantly available all around us, air source heat pumps can reduce energy costs, especially when compared to oil and LPG heating systems, plus they’re virtually maintenance free. Our relatively mild winter temperatures in the UK mean a properly installed air source heat pump system can achieve excellent levels of efficiency and performance throughout the year.

How Does a Heat Pump Work?

Heat pumps use electricity to move heat from one environment to another, much like a reverse fridge. They draw warmth out of cold air using a refrigerant liquid and can keep your home warm even when temperatures outside are as low as -16ºC.

The heat pump system is often highly efficient, averaging around 300% fuel efficiency. This means that for every 1 unit of electricity you buy, your heat pump will provide 3 units of heat. Though this will vary, day by day, 300% is considered to be the average.

Heat from the air is absorbed at low temperature into a fluid. This fluid then passes through a compressor where its temperature is increased, and transfers its higher temperature heat to the heating and hot water circuits of the house. There are two main types of air source heat pump systems.

Air-to-water
An air-to-water system distributes heat via your wet central heating system. Heat pumps work much more efficiently at a lower temperature than a standard boiler system would. This makes them more suitable for underfloor heating systems or larger radiators, which give out heat at lower temperatures over longer periods of time.

Air-to-air
An air-to-air system produces warm air which is circulated by fans to heat your home. They are unlikely to provide you with hot water as well.

The benefits of an Air Source Heat Pump

  • Can provide both heating & hot water, in an air-to-water system.
  • Can gather heat for your home when outside temperatures are as low as -16ºC
  • After the installation of an ASHP, you can expect the system to run for 20 years
  • Most systems will come with at least a 10 year warranty
  • No fuel deliveries are needed as the system runs off of electricity through the mains
  • System is highly efficient with fuel, making it cost effective
  • Is widely recognised as a renewable heating option, as it offsets CO2 due to it’s efficiency, despite running off electricity
  • Can work fantastically alongside solar PV panels
  • System is most efficient when heating is set to a lower temperature, over a longer period of time. This will also keep the whole home warmer overall, too!
  • Underfloor heating is highly recommended for an air-to-water system, for added efficiency and luxury
  • With an air-to-air system, fans can heat and cool your home, but not provide hot water

Is an air source heat pump suitable for me?

To tell if an air source heat pump is right for you, there are a few key questions to consider:
Do you have somewhere to put it? You’ll need a place outside your home where a unit can be fitted to a wall or placed on the ground. It will need plenty of space around it to get a good flow of air. A sunny wall is ideal.
Is your home well insulated? Since air source heat pumps work best when producing heat at a lower temperature than traditional boilers, it’s essential that your home is well insulated and draught-proofed for the heating system to be most efficient.
What fuel will you be replacing? The system will pay for itself much more quickly if it’s replacing an electricity or coal heating system. Heat pumps may not be the best option for homes using mains gas.
What type of heating system will you use? Air source heat pumps can perform better with underfloor heating systems or warm air heating than with radiator-based systems because of the lower water temperatures required.
Is the system intended for a new development? Combining the installation with other building work can reduce the cost of installing the system.

Servicing and Maintenance

Servicing and maintenance schemed offered, either on an individual basis or as an annual contract. Please contact Alistair to discuss your requirements.