Green Energy

Green Energy

Green Energy

Heating your pool with energy absorbed from the air around you:

Air source heat pumps absorb heat from the outside air. This heat can then be used to heat radiators, underfloor heating systems, warm air convectors and hot water in your home, but is especially useful for heating your swimming pool water

An air source heat pump extracts heat from the outside air in the same way that a fridge extracts heat from its inside. It can get heat from the air even when the  temperature is as low as -15° C. depending on the make and model. From personal experience of the industry and our wonderful British summers, a unit designed in Florida is normally designed for their summers and works wonderfully at a steady 28 degrees and glorious sun shine. Here in the UK, although better then we all complain about, we have a little less sun and a considerably lower average temperature.

I am a loyal Calorex installer because I know it works well and has been designed to work here in the UK, but I have installed many different makes and models for clients. Some have been shipped over from the USA some from Europe. There is now a huge competition which is helping to keep the prices down.

Whichever make you choose make sure it is sized correctly to get your pool to the right temperature and if you are unsure then the bigger model is the sensible option. There is no point investing your money only to find that during a poor summer like the last two you can’t get your pool up to the 30 degrees the ladies of the house require. Running a heat pump 24 hours a day to maintain a required temperature is not a wise/clever investment. Heat pumps have some impact on the environment as they need electricity to run and with pools a pump running at the same time to keep the pool water circulating through it.

Is an air source heat pump suitable for me?:

Do you have somewhere to put it?

You’ll need a area outside near your existing filtration system or if you are able to duct the air in and out of a plant room the unit can go inside. It needs plenty of space around it to obtain a good flow of air. A sunny wall is ideal. What you don’t want is the cold air being sucked back into the unit.

Is the power to your plant room large enough?

Many plant rooms around the country are quite a distance from the main house supply and sometimes pool builders would not have allowed for the voltage drop over a long run. Heat pumps run at very low levels of power but at start up draw up to 30amps. Although modern soft start systems are available you need to make sure you have enough power to deal with that demand.

What fuel will you be replacing?

The system will pay for itself much more quickly if it’s replacing an electricity system (approximately 4 years in most cases). With Gas and Oil the pay back time is a little longer.
Having both fossil and air source is ideal as it gives you the control of the pool temperature. Run them in series so you can boost the pool temp if necessary. If you like a UK extended season (April – October) this is essential. Standard summer as we refer to May – September tends to have warm enough evening temperatures to allow a heat pump to deal with maintaining the temperature.


Heat pump systems typically come with a 10 year warranty. You can expect them to operate for 20 years plus.

They do not require regular maintenance. A yearly check by you and a more detailed check by a professional installer every 3-5 years should be sufficient. The installer should leave written details of any maintenance checks you should undertake to ensure everything is working properly.

One of the yearly checks that you are likely to be advised to carry out is to check that the air inlet grill and evaporator are free of leaves or other debris. Any plants that have started to grow near the heat pump unit will also need to be removed.

To prevent the heat pump from freezing in cold winter weather anti-freeze is used. Levels of anti-freeze and its concentration is one of the things that a professional installer will check when he comes to service your heat pump.

In a nut shell

If you plan to stay at your property for 5 or more years it is definitely worth installing
Always get the bigger machine if you are unsure or borderline
Have both heat pump and Gas oil or electric if possible so if you suddenly decide to heat the pool up for a party you can.
Get a swimming pool engineer to carry out the installation
Make sure there is good airflow
Enjoy the pool as much as our summers allow

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