Is Vaillant or Mitsubishi the better heat pump?

For most UK homes, the Mitsubishi Ecodan is the safer all-rounder — proven reliability, 5-year warranty and market-leading cold-weather performance down to -28°C. The Vaillant aroTHERM plus is the efficiency champion with a class-leading SCOP above 5.0 and a longer 7-year warranty, but it's slightly less proven in freezing conditions.

Which heat pump is more efficient: Vaillant or Mitsubishi?

The Vaillant aroTHERM plus leads on efficiency with a Seasonal Coefficient of Performance (SCOP) around 5.03, comfortably above the Mitsubishi Ecodan's ~4.5. In practice a higher SCOP means lower running costs, but the Mitsubishi's performance gap narrows in cold weather where it's built to excel.

How much does a Vaillant vs Mitsubishi heat pump cost?

Both typically land in the £3,500–£8,500 range after the £7,500 Boiler Upgrade Scheme grant for a standard 3-bed install. Vaillant units are often priced slightly above Mitsubishi equivalents, partly because of the efficiency and longer warranty.

Which has the better warranty, Vaillant or Mitsubishi?

Vaillant offers a 7-year warranty on the aroTHERM plus, while the Mitsubishi Ecodan comes with a 5-year warranty. If long-term cover matters most, Vaillant has the edge on paper — but make sure you register the product within the required window.

Which brand is better for cold UK winters?

Mitsubishi's Ecodan HyperCore is engineered for cold climates and keeps operating effectively down to -28°C, making it the stronger choice for colder, northern UK locations. The Vaillant aroTHERM plus is excellent but is less specifically optimised for freezing temperatures.

Is Vaillant or Mitsubishi the better heat pump?

For most UK homes, the Mitsubishi Ecodan is the safer all-rounder — proven reliability, 5-year warranty and market-leading cold-weather performance down to -28°C. The Vaillant aroTHERM plus is the efficiency champion with a class-leading SCOP above 5.0 and a longer 7-year warranty, but it's slightly less proven in freezing conditions.

Which heat pump is more efficient: Vaillant or Mitsubishi?

The Vaillant aroTHERM plus leads on efficiency with a Seasonal Coefficient of Performance (SCOP) around 5.03, comfortably above the Mitsubishi Ecodan's ~4.5. In practice a higher SCOP means lower running costs, but the Mitsubishi's performance gap narrows in cold weather where it's built to excel.

How much does a Vaillant vs Mitsubishi heat pump cost?

Both typically land in the £3,500–£8,500 range after the £7,500 Boiler Upgrade Scheme grant for a standard 3-bed install. Vaillant units are often priced slightly above Mitsubishi equivalents, partly because of the efficiency and longer warranty.

Which has the better warranty, Vaillant or Mitsubishi?

Vaillant offers a 7-year warranty on the aroTHERM plus, while the Mitsubishi Ecodan comes with a 5-year warranty. If long-term cover matters most, Vaillant has the edge on paper — but make sure you register the product within the required window.

Which brand is better for cold UK winters?

Mitsubishi's Ecodan HyperCore is engineered for cold climates and keeps operating effectively down to -28°C, making it the stronger choice for colder, northern UK locations. The Vaillant aroTHERM plus is excellent but is less specifically optimised for freezing temperatures.

Vaillant vs Mitsubishi Heat Pump — Which Is Best for Your Home?

A head-to-head of the UK’s two most popular air source heat pump brands — efficiency, cold-weather performance, noise, warranty and price.

Choose the Mitsubishi Ecodan if you want a proven, cold-weather-ready system (it keeps working down to -28°C) with a 5-year warranty. Choose the Vaillant aroTHERM plus if you want the highest efficiency (SCOP ~5.03) and a longer 7-year warranty. Both cost broadly the same after the £7,500 grant — typically £3,500–£8,500 for a 3-bed install.

1. Cost & price

Price point	Vaillant aroTHERM plus	Mitsubishi Ecodan HyperCore
3-bed installed, before grant	£8,000 – £13,000	£7,000 – £12,000
After £7,500 grant	£3,500 – £9,000	£3,500 – £8,500

2026 guide figures. Vaillant is often a little dearer on the unit price; the efficiency and warranty are part of what you’re paying for.

2. Problems & drawbacks

Vaillant aroTHERM plus

Less specifically optimised for freezing conditions than Mitsubishi — if you’re in a very cold, northern location, the Ecodan’s cold-climate engineering has an edge. Units can also carry a slight price premium.

Mitsubishi Ecodan

A shorter 5-year warranty than Vaillant’s 7, and its headline SCOP (~4.5) trails Vaillant’s ~5.03 — so its running costs are marginally higher on a like-for-like, well-insulated home.

3. Versus: spec table

Spec	Vaillant aroTHERM plus ✱ winner	Mitsubishi Ecodan HyperCore
SCOP (efficiency)	5.03	~4.5
Cold-weather limit	Good to ~-20°C	-28°C
Noise level	37–43 dB	38–46 dB
Refrigerant	R290	R32
Max flow temperature	75°C	60°C
Warranty	7 years	5 years
Price after grant	£3,500 – £9,000	£3,500 – £8,500

4. Who each is for

Pick Vaillant if…

You want the lowest running costs and longest warranty, have a reasonably insulated home, and the higher-R290 efficiency matters more than extreme-cold margin. Ideal for most of southern and central England.

Pick Mitsubishi if…

You’re in a cold, northern UK location, want a proven, dependable all-rounder, or want the price edge on a tighter budget. The -28°C cold-weather capability is a real plus for exposed properties.

Compare live quotes from certified installers

Installers mix and match brands — ask for a Vaillant and a Mitsubishi quote side by side, both with the £7,500 grant applied. Enter your postcode to get started.

Before you pay a penny

You could be £7,500 better off

The government’s Boiler Upgrade Scheme gives every eligible homeowner £7,500 toward a new heat pump — paid straight to your installer, so it comes off your quote. No income means test and it covers most of the cost of a typical air source heat pump.

Check your grant eligibility →

Your name *

Email *

Phone

Postcode *

Property type

Property age

Current heating

Budget (after grant)

Timeline

Anything else? (preferred brands, rooms to heat, access notes)

By submitting, you agree to be contacted by up to 3 local MCS-certified heat pump installers. See our privacy policy.

5. Verdict

There’s no wrong answer between these two — both are dependable, popular air source heat pumps. Pick Mitsubishi for cold-climate reliability and proven cold-weather performance. Pick Vaillant for best-in-class efficiency (SCOP 5+) and a longer 7-year warranty. Either way, get 3 written quotes that itemise the cylinder and radiator upgrades, with the £7,500 grant applied.

More on heat pumps

The 10 best heat pumps in the UK, compared →

How much does a heat pump cost? →

Heat pump vs gas boiler running cost →

£7,500 Boiler Upgrade Scheme grant →

Find an MCS-certified installer →

Vaillant vs Mitsubishi FAQs

FAQ

Vaillant vs Mitsubishi frequently asked questions

Is Vaillant or Mitsubishi the better heat pump?: For most UK homes, the Mitsubishi Ecodan is the safer all-rounder — proven reliability, 5-year warranty and market-leading cold-weather performance down to -28°C. The Vaillant aroTHERM plus is the efficiency champion with a class-leading SCOP above 5.0 and a longer 7-year warranty, but it's slightly less proven in freezing conditions.
Which heat pump is more efficient: Vaillant or Mitsubishi?: The Vaillant aroTHERM plus leads on efficiency with a Seasonal Coefficient of Performance (SCOP) around 5.03, comfortably above the Mitsubishi Ecodan's ~4.5. In practice a higher SCOP means lower running costs, but the Mitsubishi's performance gap narrows in cold weather where it's built to excel.
How much does a Vaillant vs Mitsubishi heat pump cost?: Both typically land in the £3,500–£8,500 range after the £7,500 Boiler Upgrade Scheme grant for a standard 3-bed install. Vaillant units are often priced slightly above Mitsubishi equivalents, partly because of the efficiency and longer warranty.
Which has the better warranty, Vaillant or Mitsubishi?: Vaillant offers a 7-year warranty on the aroTHERM plus, while the Mitsubishi Ecodan comes with a 5-year warranty. If long-term cover matters most, Vaillant has the edge on paper — but make sure you register the product within the required window.
Which brand is better for cold UK winters?: Mitsubishi's Ecodan HyperCore is engineered for cold climates and keeps operating effectively down to -28°C, making it the stronger choice for colder, northern UK locations. The Vaillant aroTHERM plus is excellent but is less specifically optimised for freezing temperatures.

Sources & cited data

Vaillant aroTHERM plus specifications — https://www.vaillant.co.uk/
Mitsubishi Ecodan HyperCore specifications — https://les.mitsubishielectric.co.uk/

SCOP, noise, refrigerant and cold-weather figures are manufacturer specifications, cross-checked against the UK Air Con Tracker heat pump comparison. Price ranges are 2026 guide figures after the Boiler Upgrade Scheme grant.