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.
For older Hampshire homes with microbore pipework, a higher flow temperature can avoid lifting floors to replace pipes. Older homes around Hampshire often need a discreet unit position, such as a rear courtyard, which the survey looks for first. In Hampshire, rooms with large bay windows are often the ones where radiator output is checked most carefully.
Who it suits
- Rooms with no wall space for a larger radiator
- Older homes where insulation improvements are limited
- Period and listed homes where the radiators are part of the character
- Homes with microbore pipework that would be disruptive to replace
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 Hampshire
Here are typical prices for high-temperature heat pumps in Hampshire, 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 Hampshire
We cover 23 towns in Hampshire for high-temperature heat pumps. Each links to local guide prices and the grant position for England.
| Town | Postcode district | Nearest town | Midwinter daylight |
|---|---|---|---|
| Southampton | SO14 | Totton | 7 h 56 min |
| Portsmouth | PO1 | Gosport | 7 h 57 min |
| Basingstoke | RG21 | Alton | 7 h 52 min |
| Gosport | PO12 | Portsmouth | 7 h 57 min |
| Waterlooville | PO7 | Havant | 7 h 56 min |
| Farnborough | GU14 | Aldershot | 7 h 52 min |
| Eastleigh | SO50 | Southampton | 7 h 55 min |
| Winchester | SO23 | Eastleigh | 7 h 54 min |
| Havant | PO9 | Waterlooville | 7 h 56 min |
| Andover | SP10 | Winchester | 7 h 52 min |
| Fareham | PO16 | Gosport | 7 h 56 min |
| Aldershot | GU11 | Farnborough | 7 h 52 min |
| Fleet | GU51 | Farnborough | 7 h 52 min |
| Totton | SO40 | Southampton | 7 h 55 min |
| New Milton | BH25 | Lymington | 7 h 57 min |
| Bordon | GU35 | Alton | 7 h 53 min |
| Yateley | GU46 | Fleet | 7 h 51 min |
| Alton | GU34 | Bordon | 7 h 53 min |
| Romsey | SO51 | Totton | 7 h 55 min |
| Fordingbridge | SP6 | Ringwood | 7 h 55 min |
| Lymington | SO41 | New Milton | 7 h 57 min |
| Petersfield | GU31 | Bordon | 7 h 55 min |
| Ringwood | BH24 | Fordingbridge | 7 h 56 min |
High-temperature heat pumps questions
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.
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.
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.
Why do many high-temperature units use R290?
R290 is propane, a natural refrigerant with a very low global warming impact. Its properties make higher water temperatures more achievable than with some earlier refrigerants. Because it is flammable, manufacturers set clearance zones around the outdoor unit from windows, doors, drains and other openings, which the survey uses when choosing a position.