Brand comparison · Updated monthly

Best Heat Pump Brands UK 2026 — Independent Comparison

Last reviewed · 11 minute read

Eight brands account for the vast majority of UK heat pump installs in 2026. This page is the honest version of "which one's best" — including which one is right for your house, your installer's expertise, and your budget. We're independent: we don't sell heat pumps, we don't take referral commission that varies by brand.

At-a-glance comparison

BrandBest forSCOP (typical UK)WarrantyPrice tier
Mitsubishi EcodanLargest network, quietest, reliability3.0–3.45 years (extendable)Mid-upper
Vaillant aroTHERM PlusRetrofit (higher flow temps)3.2–3.65 yearsMid-upper
Daikin Altherma 3Cold climates, app polish3.0–3.55 yearsUpper
Samsung EHS Mono Gen7Value2.8–3.35 yearsLower
Grant Aerona3UK/Irish climate; longest warranty3.0–3.47 yearsMid
Worcester Bosch Compress 5800iCompact installs, familiar brand2.9–3.37 yearsMid-upper
Octopus Cosy 6Best total package via Octopus3.0–3.4 (Daikin platform)5 years + Octopus 10-year serviceLower (subsidised)
LG Therma VReasonable mid-tier2.8–3.25 yearsMid

Mitsubishi Ecodan — the safe default

The most-installed heat pump in UK homes. Mitsubishi's Ecodan range has been the UK market leader since the early 2010s, and the installer network is broader than any rival — meaning more competition on price and easier access to service support.

Strengths

  • Quietest unit on the market — 45 dB(A) at 1m. Important if your outdoor unit will be near a neighbour's bedroom or against a party wall.
  • Output to −15°C, well within UK climate range.
  • Largest installer network in the UK — easy to find local expertise.
  • Reliability record is strong; rare for the outdoor unit to fail before warranty end.
  • Native integration with Cosy Octopus and most smart tariff platforms.

Watch for

  • Premium pricing — typically 10–15% above value brands for similar specs.
  • Some installers default to Mitsubishi without checking alternatives. Push them to justify the choice for your specific property.
  • Refrigerant: R32 (lower GWP than older R410A but higher than R290 from Vaillant).

Best for: typical UK semi-detached or detached homes with good installer access, where reliability and quiet operation are priorities.

Vaillant aroTHERM Plus — the retrofit specialist

Vaillant's aroTHERM Plus uses R290 (propane) refrigerant — a natural refrigerant with very low global warming potential. The key technical advantage: it can deliver flow temperatures up to 75°C, meaning fewer radiator changes in retrofit scenarios.

Strengths

  • Best heat pump for retrofitting older UK homes with existing radiators sized for gas boiler flow temperatures.
  • R290 refrigerant — future-proof, lowest GWP.
  • SCOP up to 4.0 in well-installed systems.
  • Excellent installer training programme; strong Vaillant-specialist installer base.

Watch for

  • R290 is mildly flammable — outdoor unit needs proper siting (typically 1m+ from openings, no enclosed spaces).
  • The higher flow temperature option tempts installers to skip radiator upgrades, leaving the heat pump running hot and inefficient. Push for proper sizing even with Vaillant capability.
  • Slightly louder than Mitsubishi (~48 dB(A)).

Best for: Victorian/Edwardian terraces, 1930s semis, or any property where extensive radiator changes are impractical or undesirable.

Daikin Altherma 3 — the polished one

Daikin is one of the world's largest HVAC manufacturers. The Altherma 3 is their UK domestic flagship.

Strengths

  • Operates to −28°C — far beyond UK temperatures, but useful for northern Scotland or high-altitude properties.
  • Inverter compressor — better part-load efficiency than fixed-speed competitors.
  • Strong reliability record (some of the longest-running UK heat pump fleets are Daikin).
  • Underpins Octopus Cosy 6 — same hardware, different commercial wrapper.

Watch for

  • App ecosystem (Onecta) is less polished than Mitsubishi's MELCloud.
  • Premium pricing.

Best for: homes in colder UK regions or where you want a robust, well-engineered unit with deep R&D backing.

Samsung EHS Mono Gen7 — the value choice

Samsung has been making heat pumps for the UK market for over a decade. The Mono Gen7 is the current model — significantly improved over earlier generations (which had a poor reputation for reliability).

Strengths

  • Cheapest hardware in the major-brand category — often £1,500–£2,500 less than Mitsubishi for similar specs.
  • 2024–26 units have much improved component quality vs 2018–2022 generations.
  • Compact units (suit narrow side returns and small gardens).

Watch for

  • Generation-sensitive reliability. If an installer offers you a "Samsung heat pump" without specifying the model year, push back — older units genuinely had issues.
  • Smaller installer network than Mitsubishi or Daikin.
  • Slightly lower SCOPs than premium brands (~0.2 difference).

Best for: budget-conscious households on Gen7 specifically — older Samsung units we'd avoid.

Grant Aerona3 — Irish-designed for UK climate

Grant Engineering is an Irish family company specialising in heating for the UK/Irish climate. The Aerona3 is their flagship heat pump.

Strengths

  • 7-year warranty — longest of any major UK brand.
  • Specifically engineered for damp, mild, variable UK/Irish conditions.
  • Strong installer network in Ireland and rural England; growing in the rest of the UK.
  • Reliable, no-frills product.

Watch for

  • Smaller installer network than market leaders, especially in urban Scotland and central London.
  • Less sophisticated controls than Mitsubishi/Daikin.

Best for: rural and semi-rural UK households where warranty longevity matters and you have access to a competent Grant installer.

Worcester Bosch Compress 5800i — the boiler-brand carryover

Worcester Bosch is the most-installed boiler brand in the UK. Their heat pump range — Compress 5800i in 2026 — leverages that brand familiarity.

Strengths

  • Compact unit, particularly easy to fit in tight UK side returns.
  • Brand recognition — homeowners trust Worcester Bosch from their boiler experience.
  • 7-year warranty.
  • Heavy investment in installer training.

Watch for

  • Slightly more expensive than direct-equivalent Mitsubishi or Daikin for similar specs.
  • Newer product line — fewer long-term field data points than market leaders.

Best for: households who want a familiar brand with strong installer support and don't mind paying slightly more for it.

Octopus Cosy 6 — the value-bundle play

Octopus Energy Services sells Cosy 6 heat pump installs at ~£500 net cost after BUS + Octopus's own subsidy. Hardware is the Daikin Altherma 3 platform with Octopus branding and installer network.

Strengths

  • Cheapest install in the UK for many households — Octopus can deliver under £1,500 net for typical properties.
  • Native Cosy Octopus tariff integration — best running cost economics out of the box.
  • 10-year service plan included.
  • UK's leading heat pump installer (40,000+ installs by end-2025; ~15% market share of BUS-funded installs).

Watch for

  • Tied to Octopus. If you don't want Octopus as your import supplier, this isn't for you.
  • Octopus's installer network covers most of the UK but check it covers your postcode before committing.
  • Cosy 6 is a specific product — if your property needs ground source or air-to-air, Octopus may push you toward a different solution.

Best for: households happy to be Octopus customers and who fit the standard 6kW air source heat pump specification.

Brand vs installer — which matters more?

A widely-shared truism in the UK heat pump industry: installer quality matters more than brand. A well-tuned Samsung at SCOP 3.3 beats a badly-tuned Mitsubishi at SCOP 2.5 every time.

That said, brand still matters for:

  • Warranty length and reliability. Grant's 7-year warranty is genuinely longer than Mitsubishi's 5-year.
  • Noise. If the outdoor unit will be near a neighbour's window, the 45 dB(A) of Mitsubishi vs 50 dB(A) of others is genuinely noticeable.
  • Cold-weather performance. If you're in northern Scotland, Daikin's −28°C operating range is real upside.
  • App ecosystem. Mitsubishi's MELCloud and Octopus Cosy's bundled app are notably better than Daikin's Onecta or Samsung's SmartThings.

How to pick your brand — decision framework

Step 1: Find 2-3 quality installers near you

Use the MCS find an installer tool for the baseline, then cross-check with Heat Geek for the quality tier. Some installers are brand specialists (e.g. Vaillant-only); others are multi-brand.

Step 2: Ask each installer their first and second choice for your property

Note the brands they pick. If two installers independently pick the same brand, that's a strong signal. If they disagree, ask each one specifically why their pick is right for your property.

Step 3: Match brand to your priority

  • Cheapest install: Octopus Cosy 6 (if Octopus covers your area) → Samsung Gen7 → Grant.
  • Retrofit (existing radiators): Vaillant aroTHERM Plus → Worcester Bosch → Mitsubishi.
  • Reliability: Mitsubishi → Daikin → Grant.
  • Quiet operation: Mitsubishi → Daikin → Grant.
  • Cold UK regions: Daikin → Mitsubishi → Vaillant.
  • Long warranty: Grant (7 years) → Worcester Bosch (7 years) → Octopus (10-year service plan).

Step 4: Get the same brand from at least two installers

Once you've narrowed to a brand, get at least two quotes for the same brand. Price variance is often 30%+ even on identical specs.

Frequently asked questions

What's the most reliable UK heat pump brand?

Mitsubishi, Daikin and Grant top the reliability surveys (e.g. Which? customer satisfaction). All three have low rates of out-of-warranty failure based on Trustpilot and industry data. Vaillant and Worcester Bosch are close behind. Samsung's reputation suffered from older generations but Gen7 (2024+) is now competitive.

Is the brand really less important than the installer?

Yes, by a wide margin. A good Vaillant install in a Victorian house will return SCOP 3.4; a bad Mitsubishi install in the same house returns SCOP 2.4. The 1.0 SCOP difference is a 40% running cost difference — bigger than any brand-to-brand variation. Always vet the installer first.

Which heat pump brand is the quietest?

Mitsubishi Ecodan, at 45 dB(A) at 1m. Daikin and Grant follow at ~47 dB(A). Most other brands sit at 48–52 dB(A). The difference is audible if the outdoor unit is near a bedroom or shared boundary.

Are Chinese-brand heat pumps any good?

Mixed. Established Chinese brands like Mitsubishi Heavy Industries (now MHI-mostly outside this market) and Haier produce decent units. Newer entrants vary widely in quality. The big risk isn't the hardware but post-sale support — if a Chinese brand exits the UK market (as some have), your warranty is in trouble. Stick with brands that have a multi-decade UK service track record.

What's the cheapest heat pump brand?

Octopus Cosy 6 (Daikin platform, Octopus subsidy) is the cheapest installed for most UK households at ~£500 net post-grant. Direct hardware-cost basis: Samsung EHS Mono Gen7 is typically lowest. Grant Aerona3 sits at the value-end of the mid-tier.

Should I be worried about an installer's brand preference?

Slightly. Some installers are brand-loyal because of margin or training relationships, not because that brand is best for your house. Always ask why they're recommending a specific brand, and get at least one second opinion from an installer with different brand options.

Sources

Page changelog

  • 19 May 2026 — Initial publication.

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