10 Heat Pump Myths Debunked by Actual Installers

False. Modern R290 heat pumps like the Vaillant aroTHERM Plus operate down to -22°C. They work across the full range of UK winter temperatures. The key is proper system design — sizing the unit for the coldest expected day so it always has capacity to spare.

False. An air source heat pump outdoor unit needs about 1m² of space with adequate airflow. It can go on a patio, driveway, or side passage. You do not need acres of garden. We have installed heat pumps in terraced houses and compact town houses successfully.

Largely false. A modern unit produces about 48 dB(A) at 3 metres — quieter than a normal conversation. At your neighbour’s window, it is typically below 40 dB(A). We carry out a formal MCS noise assessment for every installation to ensure compliance.

False. In our experience, 30–40% of existing radiators can stay as they are. Others may need upsizing. A full rip-out is extremely rare. We assess every radiator during the survey and include any necessary upgrades in the quote.

Misleading. After the £7,500–£9,000 BUS grant and 0% VAT, a heat pump installation starts from around £4,000–£6,000. Running costs are lower than gas. Over 15–20 years, total cost of ownership is often less than a succession of gas boilers.

False. The Vaillant aroTHERM Plus produces hot water at up to 75°C without a backup immersion. Combined with the Heat Geek Super Cylinder, hot water recovery is fast and reliable. We size the cylinder for your household’s specific needs.

False. While UFH is the ideal partner, heat pumps work perfectly well with radiators. The key is designing for lower flow temperatures and ensuring radiators are appropriately sized. Most of our installations use a mix of radiators and UFH.

Partially true. Better insulation means a smaller, cheaper heat pump and lower running costs. But heat pumps work in older properties too — they just need to be sized correctly. We have successfully installed systems in Victorian terraces and 1930s semis.

Not any more. The Vaillant aroTHERM Plus uses R290 (propane) — a natural refrigerant with a Global Warming Potential (GWP) of just 3, compared to over 2,000 for older HFC refrigerants. R290 is the future of the heat pump industry.

Technically yes, practically no. MCS certification is required for grant eligibility, and Heat Geek training is what separates good installations from bad ones. The unit itself is just hardware — it is the design, sizing, commissioning, and weather compensation setup that determines whether you love your heat pump or regret it. Always choose a qualified, experienced installer.