A high-temperature heat pump is an air-to-water heat pump able to produce flow temperatures of around 65–75°C, close to what a gas or oil boiler delivers, instead of the 35–50°C at which standard heat pumps run most efficiently. That means existing radiators can often heat rooms much as they do now, without being replaced with larger ones.
A survey in Cornwall can compare a high-temperature unit with upsizing a few radiators, for homes anywhere in Cornwall. Period houses in Cornwall with original cast-iron radiators may suit a high-temperature unit that works with them. In Cornwall, rooms with large bay windows are often the ones where radiator output is checked most carefully.
Who it suits
- Owners who want fewer changes inside the house
- Older homes where insulation improvements are limited
- Rooms with no wall space for a larger radiator
- Period and listed homes where the radiators are part of the character
Grants and rules for heat pumps in England
In England the Boiler Upgrade Scheme gives £7,500 towards an air source heat pump (£9,000 if it replaces oil or LPG, from 21 July 2026 to 31 March 2027), and since 28 April 2026 a valid EPC is no longer needed. The grant is applied for by the MCS-certified installer and shown as a deduction on your quote.
There is no VAT on installing a heat pump anywhere in the UK until 31 March 2027. In England most houses can have an air source heat pump under permitted development, provided the unit meets the MCS noise and siting standards; the old 1 m boundary limit was removed on 29 May 2025. We flag listed buildings, flats and sensitive conservation-area positions at survey.
High-temperature heat pumps prices in Cornwall
Here are typical prices for high-temperature heat pumps in Cornwall, installed and including VAT. Use the guide price tool for a figure based on your home, then a survey confirms it in writing.
| Home | Typical size | Installed guide price | After £7,500 grant |
|---|---|---|---|
| 1–2 bedroom flat or small terrace | 4–5 kW | £9,800–£12,900 | £2,300–£5,400 |
| 2–3 bedroom terrace or semi | 5–7 kW | £10,800–£13,900 | £3,300–£6,400 |
| 3 bedroom semi or small detached | 6–9 kW | £12,350–£15,950 | £4,850–£8,450 |
| 4 bedroom detached | 8–12 kW | £14,400–£18,550 | £6,900–£11,050 |
| 5+ bedroom or larger older house | 11–16 kW | £17,000–£23,200 | £9,500–£15,700 |
Installed, inc VAT: unit, cylinder, controls, minor pipework and commissioning. A high-temperature unit typically adds £1,500–£3,000.
Towns we cover in Cornwall
We cover 15 towns in Cornwall for high-temperature heat pumps. Each links to local guide prices and the grant position for England.
| Town | Postcode district | Nearest town | Midwinter daylight |
|---|---|---|---|
| Redruth | TR16 | Camborne | 8 h 02 min |
| Falmouth | TR11 | Truro | 8 h 03 min |
| St Austell | PL25 | Bodmin | 8 h 01 min |
| Truro | TR1 | Falmouth | 8 h 02 min |
| Camborne | TR14 | Redruth | 8 h 02 min |
| Newquay | TR7 | Truro | 8 h 00 min |
| Penzance | TR18 | Hayle | 8 h 03 min |
| Bodmin | PL31 | Wadebridge | 8 h 00 min |
| Saltash | PL12 | Plymouth | 8 h 00 min |
| Bude | EX23 | Launceston | 7 h 56 min |
| Hayle | TR27 | Camborne | 8 h 02 min |
| Helston | TR13 | Camborne | 8 h 03 min |
| Launceston | PL15 | Liskeard | 7 h 58 min |
| Liskeard | PL14 | Saltash | 8 h 00 min |
| Wadebridge | PL27 | Bodmin | 7 h 59 min |
High-temperature heat pumps questions
Are high-temperature heat pumps less efficient?
Yes, when they run hot. Every heat pump uses more electricity per unit of heat as the flow temperature rises, so a unit running at 70°C is less efficient than one running at 45°C. With weather compensation it runs cooler for much of the year, which narrows the gap. The design aims to keep the maximum temperature as low as your radiators allow.
Are high-temperature heat pumps eligible for the grant?
In England and Wales, yes. A high-temperature unit is an air-to-water heat pump, so eligible owners of existing homes can receive £7,500 through the Boiler Upgrade Scheme, or £9,000 when replacing oil or LPG within the published dates. Scotland's Home Energy Scotland funding has its own conditions, and Northern Ireland has no dedicated homeowner grant at present.
Is a high-temperature heat pump right for a listed building?
It can be, because it reduces the need to replace period radiators or lift historic floors for new pipework. The outdoor unit position still matters: in England, listed buildings need listed building consent for external works, and the other nations have their own rules. We check what applies at survey and look for discreet positions, such as a rear courtyard or behind an outbuilding.
Do I still need a hot water cylinder?
Yes. Like other air-to-water heat pumps, a high-temperature unit heats a stored cylinder rather than supplying hot water on demand. Its higher output temperature can help the cylinder reach the temperature needed for its periodic legionella cycle with less reliance on the immersion heater. The cylinder is sized for your household at survey.