Vaillant Review UK (2026)
Quick Answer
Premium German-engineered air source heat pump — strong installer network and natural refrigerant (R290).
Data verified April 2026. UK installed pricing varies with installer, site and package.
At a Glance
| Origin | Germany (founded 1874; heat pumps since the 1970s) |
| UK support | Strong — large UK installer and service network, significant G.A.S. partnership |
| Capacity / sizing | 3.5 kW – 15 kW (aroTHERM plus range) — single family to larger homes |
| SCOP | 4.5+ at 35°C flow (aroTHERM plus, A7/W35) |
| Warranty | 5 years standard; up to 10 years via accredited installer (G.A.S.) |
| Indicative UK price | £9,000–£14,000 installed before BUS grant (-£7,500) |
Strengths
- R290 natural refrigerant — lower global warming potential and aligns with upcoming F-gas regulations
- Widely installed in the UK — service and parts easy to source
- Strong control ecosystem (sensoCOMFORT, myVAILLANT app) with integrated cylinder
- Compatible with high flow-temp applications — better suited to older UK housing stock with existing radiators
Weaknesses
- More expensive than Mitsubishi or Samsung equivalents
- Noise levels slightly higher than some rivals — check sound rating for boundary conditions
- Larger footprint outdoor unit than Mitsubishi Ecodan
Who Vaillant Suits Best
Older UK homes that keep existing radiators (70°C capable with aroTHERM), or homeowners who want a long-established European brand with strong service.
When to Avoid
You need the most compact outdoor unit, or budget is the primary driver — Samsung or Mitsubishi often come in lower.
Popular Models
- aroTHERM plus VWL 35/6 A 230V
- aroTHERM plus VWL 75/6 A 230V (7.5 kW)
- aroTHERM plus VWL 125/6 A (12 kW)
Frequently Asked Questions
How much does a Vaillant heat pump cost in the UK?
Vaillant aroTHERM plus installations typically cost £9,000–£14,000 before the £7,500 Boiler Upgrade Scheme (BUS) grant. After BUS, net cost to the homeowner is usually £1,500–£6,500.
Is Vaillant eligible for the BUS grant?
Yes. Vaillant aroTHERM plus qualifies for the £7,500 Boiler Upgrade Scheme grant when installed by an MCS-certified installer in England and Wales.
What is the Vaillant G.A.S. warranty?
G.A.S. (Guild of Advanced Service) is Vaillant's accredited installer programme. G.A.S. installs receive up to 10 years warranty (vs 5 years standard) and priority service.
Can a Vaillant heat pump work with existing radiators?
Yes, within limits. The aroTHERM plus can run flow temperatures up to 75°C, suitable for many older UK radiator setups. A heat loss survey determines whether radiator upgrades are needed for efficient operation at lower flow temperatures.
Compare with Other Heat Pump Brands
| Brand | UK support | Warranty | Indicative price | |
|---|---|---|---|---|
| Daikin | Very strong | 3 years standard; extendable to 7 years via accredited installer | £9,500–£14,500 installed before BUS grant | View → |
| Mitsubishi Ecodan | Very strong | 7 years standard on accredited installs (Mitsubishi Electric Hybrid+ programme) | £9,000–£13,500 installed before BUS grant | View → |
| NIBE | Strong | 5 years standard; up to 10 years via VIP+ accredited installer | £10,000–£15,000 installed before BUS grant (air source); significantly more for ground source with boreholes | View → |
Get a Quote Including Vaillant
Most MCS-certified installers carry multiple heat pump brands — ask for a quote specifying Vaillant if you want a heat pump from this brand. Use the form below to reach local installers.
Sources
John Rooney is the founder of Solar Info and has been covering the UK solar energy market since 2023. He fact-checks all content against official MCS and Ofgem data and maintains relationships with MCS-certified installers across the UK.