Home Heat Pump Guide

Grant Aerona Heat Pump Review: Best Value Heat Pump in the UK

By Home Heat Pump Guide ·
UK bungalow ideally suited for an affordable Grant Aerona3 heat pump installation
The Grant Aerona3 offers the best value for money of any quality heat pump on the UK market.

Grant Engineering may not have the brand recognition of Worcester Bosch, but among installers and heating engineers, the Grant Aerona3 has built a formidable reputation. It is the heat pump that consistently delivers reliable performance at the lowest price point of any quality brand — and after the BUS grant, many homeowners pay under £2,000 out of pocket. If your priority is getting the best value per pound without sacrificing quality, the Aerona3 is hard to beat.

This review covers the Aerona3 range in detail. For comparisons with other brands, see our complete UK brand guide.

Could a Grant Aerona save you money?

Get Your Free Cost Estimate

See what you would pay after the BUS grant — takes under 2 minutes.

About Grant Engineering

Grant is an Irish manufacturer based in County Offaly, founded in 1978. Their heritage in oil-fired boilers gives them deep understanding of heating systems for homes in the British Isles — including the damp, variable climate that some continental manufacturers may not fully account for.

Grant Aerona3 Range

6–21.5kWSix Output Sizes
4.52Top SCOP
R32Refrigerant
£0–£5,500Net Cost (After Grant)

All models are monobloc units with Mitsubishi Electric compressors inside — a proven, reliable choice. The wide output range from 6kW to 21.5kW covers everything from small flats to large detached properties.

Efficiency and Real-World Performance

Grant Aerona3 Real-World COP by Heating System

With UFH (30–35°C)
COP 3.5–4.2
Oversized radiators (40–45°C)
COP 3.0–3.7
Standard radiators (50–55°C)
COP 2.5–3.0

These figures are competitive with more expensive brands. Annual running costs of £750–£1,050 for a typical three-bedroom semi are typical. The Aerona3 performs particularly well in the moderate UK climate.

UK homeowner reviewing Boiler Upgrade Scheme grant paperwork for a Grant Aerona heat pump installation
The BUS grant of up to £7,500 makes the Grant Aerona3 one of the most affordable heating upgrades available.

Installation Costs

ModelInstalled CostAfter BUS Grant
6kW£7,500–£9,500£0–£2,000
10kW (most popular)£8,500–£11,000£1,000–£3,500
13–16kW£9,500–£13,000£2,000–£5,500

After the BUS grant, the 10kW model — suitable for most UK homes — can cost as little as £1,000 out of pocket. Combine with solar panels for even greater savings on your electricity bills.

Compare Grant installer quotes in your area

Get Free Quotes

Up to 3 MCS-certified quotes — no obligation.

Grant Aerona heat pump mid-installation at a UK home showing straightforward monobloc setup
The Aerona3's monobloc design and clear documentation make for quick, efficient installations.

Pros and Cons

Advantages

  • Excellent value — one of the most affordable quality heat pumps in the UK
  • Reliable performance with Mitsubishi Electric compressors
  • Wide output range (6–21.5kW) covering most property types
  • Easy installation with good documentation
  • Strong UK/Ireland support from local manufacturer
  • Popular with installers — often means better installation quality

Disadvantages

  • R32 not R290 — may face future restrictions
  • Basic controls and app compared to premium brands
  • Less brand recognition than Worcester Bosch
  • Average noise performance — not the quietest option
  • No smart tariff integration

For advanced smart controls, consider Nibe. For brand prestige, look at Worcester Bosch. For the lowest possible running costs, Nibe and Viessmann lead on efficiency. See our manufacturer directory for the complete picture.

UK homeowner comparing energy bills showing savings after switching to a Grant Aerona heat pump
With the lowest upfront cost and solid efficiency, the Grant Aerona3 delivers quick payback on your investment.

Frequently Asked Questions

Are Grant heat pumps any good?

Yes, Grant Aerona3 heat pumps are well-regarded by homeowners and installers. They offer competitive efficiency, reliable performance, and excellent value for money.

How much does a Grant Aerona heat pump cost?

Fully installed costs range from £7,500 to £13,000. After the £7,500 BUS grant, the net cost can be as low as £0 to £5,500.

Where are Grant heat pumps made?

Ireland, by Grant Engineering in Birr, County Offaly. Manufacturing heating products since 1978.

What refrigerant does the Grant Aerona3 use?

R32, which has a lower GWP than R410A but is not as low as R290 propane used by Bosch and Nibe.

Is Grant better than Worcester Bosch?

Grant offers better value for money and comparable efficiency. Worcester Bosch has a larger installer network and greater brand recognition.

How long is the Grant Aerona warranty?

5-year standard, extendable to 7 years through G-One accredited installers.

Is Grant the best value choice for your home?

Check Your Home's Suitability

Free 2-minute assessment.

Grant and Affordable Renewable Heating

The Grant Aerona3 proves that switching to a heat pump does not have to break the bank. With the Boiler Upgrade Scheme grant, many homeowners pay under £2,000 out of pocket. Pair with solar panels to generate your own electricity and the financial case becomes even stronger. Whether you are replacing an oil boiler in a rural home or a gas boiler in the suburbs, Grant offers proven value compared to continuing with fossil fuels.