Swimming Pool Heat Pump Size Calculator UK
What Size Heat Pump Do I Need for My Pool? This is a common question among pool owners. but choosing the right heat pump is key to keeping your water warm whether you swim in summer, winter, or all year round.
Our calculator will help you work out the perfect size heat pump based on your pool’s size, type, and how often you use it.
This tool is designed for UK pool owners, with real-world recommendations based on our climate. Whether your pool is above ground, indoor, or in-ground, we’ve factored in the seasonal variations that affect heating needs.
Just enter your pool volume in litres, choose the type of pool you have, and select when you plan to use it – summer only, all year round, or during the colder months.
The calculator will give you an estimated kilowatt (kW) size that’s suitable for your setup.
Don’t know your pool volume? Use our Pool Water Volume Calculator (UK Litres)
What Size Heat Pump Do I Need for My Pool? – Frequently Asked Questions
What temperature is this calculator based on?
The calculation assumes you want to keep your pool at a typical swimming temperature — usually between 28°C and 30°C. That’s the range most UK pool owners aim for, and it matches what heat pump manufacturers use when recommending models. The calculator takes into account average heat loss and UK weather to give a realistic estimate for maintaining that temperature.
Why do I need to calculate my pool's heat pump size?
Choosing the correct size ensures your pool heats efficiently without wasting energy. Too small, and it won’t keep up — too large, and you’re overspending. Our calculator gives you a reliable starting point based on your pool size, type, and usage in the UK climate.
Does it matter if my pool is above-ground or in-ground?
Yes. Above-ground pools lose heat more quickly due to more exposed surface area, so they often need a slightly larger heat pump. Our calculator factors this in for you.
What if I use my pool all year round?
If you swim during colder months, you’ll need a more powerful heat pump. Our “All Year” option estimates the higher demand needed to maintain temperature through autumn and winter in the UK.
I’ve got an indoor pool — do I still need heating?
Most indoor pools still require heating, but they lose less heat than outdoor ones. That’s why the calculator applies a reduced power factor for indoor setups
Can I use this calculator for hot tubs?
No, this tool is designed for swimming pools. Hot tubs typically use integrated electric heaters and have different heating needs.