The trade-off is efficiency. The hotter the water a heat pump makes, the more electricity it needs for each unit of heat, so a system running at 65°C has a lower seasonal efficiency than one running at 45°C. Good design still matters: weather compensation runs the unit cooler on mild days and only raises the temperature in the coldest weather, which keeps running costs down across the year.
In Kent, rooms with large bay windows are often the ones where radiator output is checked most carefully. Period houses in Kent with original cast-iron radiators may suit a high-temperature unit that works with them. Installers in Kent set the weather compensation curve so the unit runs cooler on mild days.
Who it suits
- Homes with microbore pipework that would be disruptive to replace
- Owners who want fewer changes inside the house
- Older homes where insulation improvements are limited
- Rooms with no wall space for a larger radiator
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 Kent
The ranges below are typical installed prices for homes in Kent, including VAT. A survey sets the exact figure, because two similar-looking houses in Kent can need quite different radiators and pipework.
| 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 Kent
We cover 24 towns in Kent for high-temperature heat pumps. Each links to local guide prices and the grant position for England.
| Town | Postcode district | Nearest town | Midwinter daylight |
|---|---|---|---|
| Broadstairs | CT10 | Margate | 7 h 51 min |
| Maidstone | ME16 | Rochester | 7 h 52 min |
| Gillingham | ME7 | Rochester | 7 h 51 min |
| Royal Tunbridge Wells | TN1 | Tonbridge | 7 h 53 min |
| Folkestone | CT20 | Hythe | 7 h 54 min |
| Margate | CT9 | Broadstairs | 7 h 51 min |
| Ashford | TN24 | Tenterden | 7 h 53 min |
| Canterbury | CT1 | Whitstable | 7 h 52 min |
| Sittingbourne | ME10 | Faversham | 7 h 51 min |
| Gravesend | DA11 | Strood | 7 h 50 min |
| Ramsgate | CT11 | Broadstairs | 7 h 51 min |
| Dover | CT17 | Folkestone | 7 h 53 min |
| Tonbridge | TN9 | Royal Tunbridge Wells | 7 h 53 min |
| Strood | ME2 | Rochester | 7 h 51 min |
| Whitstable | CT5 | Herne Bay | 7 h 51 min |
| Deal | CT14 | Sandwich | 7 h 52 min |
| Sevenoaks | TN13 | Westerham | 7 h 52 min |
| Rochester | ME1 | Strood | 7 h 51 min |
| Herne Bay | CT6 | Whitstable | 7 h 51 min |
| Faversham | ME13 | Whitstable | 7 h 51 min |
| Hythe | CT21 | Folkestone | 7 h 54 min |
| Sandwich | CT13 | Deal | 7 h 52 min |
| Tenterden | TN30 | Ashford | 7 h 54 min |
| Westerham | TN14 | Sevenoaks | 7 h 52 min |
High-temperature heat pumps questions
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.
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.
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.
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.

