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Frequently Asked Questions

The following are the most common questions that people ask about heat pumps. If you have any other queries, please don’t hesitate to contact us.

How does a heat pump work?

The simple answer is that it’s like a fridge in reverse. The heat pump takes energy from the ground or air around you and, using a system of heat exchangers and compressors with a refrigerant, multiplies this up to heat which is enough to provide hot water for your heating system and also all of the hot water for your taps.

See our products pages for more details.

Will the heat pump keep me warm enough all year round?

Yes! We will ensure that the system that we design for you is sized to meet the entire heat loss of your house and to deliver all the heating and hot water that you require. The heat pump itself will work perfectly well, even in the middle of winter when it’s well below freezing outside. Our ground source systems are from leading manufacturer Stiebel Eltron, as well as Finnish company Oilon. In Finland, the outside temperature in winter can drop to -45°C so their systems take the UK winter in their stride. Our Panasonic air source units are also specifically designed for the UK climate.

How can I work out how big a system I need?

We will undertake a free survey of your home that will allow us to give you an estimate of the heat pump you need and how much it is likely to cost.

If you want to get a quick idea now, however, you could try this rough guide. Look at the number of litres of oil you have used on average over the past couple of years. Multiply this number by 10, then divide by 2,400 to give a rough idea of the heat pump size in kW that you might need. So, if you used 3,000 litres of oil, that would be 12.5 – i.e. you might need a 12.5kW heat pump. The heat pump size may well be less if you have an old boiler, as this is likely to be less efficient.

How much will a heat pump cost?

This depends on how much heat you use. Using the same four bedroom house example mentioned above, it might cost £9,000 for an air source or £17,000 for a ground source. This might sound like a significant investment, but remember the combination of your heating savings and the Boiler Upgrade Scheme payment will usually allow you to get your money back in five years or less. That represents a 20% return on investment.

How long will a heat pump last?

You should expect a good quality air source system should last 15-20 years. A ground source system should last in excess of 30 years. This compares to a modern condensing boiler which is only likely to last between seven and 10 years.

How much maintenance does a heat pump need?

Very little, because the system doesn’t involve combustion. We do however recommend that your system is checked by us each year to make sure that it’s still running as efficiently as it should.

What are the main benefits of a heat pump?

Both ground and air source heat pumps offer significant advantages over conventional heating systems such as oil and gas, or indeed alternatives such as biomass and LPG. Some of the key benefits of using a heat pump for your heating and hot water can be found on our Benefits page.

What funding is available for a heat pump?

The main funding currently available for domestic projects is the government’s Boiler Upgrade Scheme (BUS) which provides a one-off grant of £7,500 for air source or ground source projects. Heat pumps projects for homeowners also qualify for zero VAT until 2027.

See our Funding page for more details on all domestic and commercial schemes available.

Will the system work with my existing radiators or underfloor heating system?

As the flow temperature from a heat pump is a bit lower than a conventional boiler, it is possible that some of your radiators may need to be slightly increased in size. We will tell you if this is the case when we provide you with a quotation for your system. If you have underfloor heating it should be fine as this is typically designed for a flow temperature which is lower than radiators. Even if you do need a few new radiators, they are not usually very expensive.

What sort of properties can you heat with a heat pump?

Any kind of property, domestic or commercial, can be heated effectively and efficiently with a heat pump. We have installed ground and air source heat pumps in properties of all ages, shapes and sizes – everything from small bungalows and detached houses to stately homes, schools, glasshouses (greenhouses) and even a Premier League football club.

Are heat pumps new technology?

Not at all – heat pump technology was actually developed more than 150 years ago and the first ground source heat pump was brought into use over 70 years ago. Coincidentally, the UK’s first large scale heat pump was developed just down the road from us in Norwich by John Sumner in 1945. Click here to read more about the history of the heat pump.

What area does Finn Geotherm cover?

We are renewable heating experts based in Attleborough, Norfolk. Our location, just beside the A11, puts us in an ideal position to serve all of East Anglia, including customers looking for ground and air source heat pump installations in Norfolk, Suffolk, Cambridgeshire, Lincolnshire and Essex. Our heat pump expertise also takes us further afield for some projects – contact us for more details.

Why should I use Finn Geotherm for my system?

Established in 2006, we are one of the longest established heat pump companies in the UK heating, ventilation and air conditioning (HVAC) industry. We pride ourselves on being the renewable heating experts – our only business is, and has only ever been, heat pumps so we’re good at what we do! We only use equipment that we know is reliable and efficient. We also have experience in a huge range of properties of all shapes, sizes and ages for both domestic and commercial use across East Anglia and beyond, and have won numerous awards for our installations.

Take a look at our case studies for more details of our past projects.