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.
Older homes around Ayrshire often need a discreet unit position, such as a rear courtyard, which the survey looks for first. Period houses in Ayrshire with original cast-iron radiators may suit a high-temperature unit that works with them. Installers in Ayrshire set the weather compensation curve so the unit runs cooler on mild days.
Who it suits
- Rooms with no wall space for a larger radiator
- Older homes where insulation improvements are limited
- Homes with microbore pipework that would be disruptive to replace
- Period and listed homes where the radiators are part of the character
Grants and rules for heat pumps in Scotland
The Boiler Upgrade Scheme does not apply in Scotland. Instead, homeowners in Ayrshire can apply to Home Energy Scotland for a grant of up to £7,500 towards a heat pump, with up to £1,500 more for eligible rural and island homes, plus an optional interest-free loan of up to £7,500. You need a written funding offer before any work starts.
Installing heat pumps is zero-rated for VAT across the UK until 31 March 2027. Scotland has its own permitted development rules for air source heat pumps and its own building standards, so we confirm what applies to your property at survey.
High-temperature heat pumps prices in Ayrshire
Here are typical prices for high-temperature heat pumps in Ayrshire, 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 |
|---|---|---|
| 1–2 bedroom flat or small terrace | 4–5 kW | £9,500–£12,500 |
| 2–3 bedroom terrace or semi | 5–7 kW | £10,500–£13,500 |
| 3 bedroom semi or small detached | 6–9 kW | £12,000–£15,500 |
| 4 bedroom detached | 8–12 kW | £14,000–£18,000 |
| 5+ bedroom or larger older house | 11–16 kW | £16,500–£22,500 |
Installed, inc VAT: unit, cylinder, controls, minor pipework and commissioning. A high-temperature unit typically adds £1,500–£3,000. In Scotland, Home Energy Scotland grants of up to £7,500 and interest-free loans may reduce the cost.
Towns we cover in Ayrshire
We cover 11 towns in Ayrshire for high-temperature heat pumps. Each links to local guide prices and the grant position for Scotland.
| Town | Postcode district | Nearest town | Midwinter daylight |
|---|---|---|---|
| Kilmarnock | KA1 | Stewarton | 7 h 02 min |
| Ayr | KA8 | Prestwick | 7 h 04 min |
| Irvine | KA12 | Saltcoats | 7 h 02 min |
| Ardrossan | KA22 | Saltcoats | 7 h 01 min |
| Cumnock | KA18 | Prestwick | 7 h 04 min |
| Girvan | KA26 | Ayr | 7 h 07 min |
| Largs | KA30 | Ardrossan | 6 h 59 min |
| Prestwick | KA8 | Ayr | 7 h 04 min |
| Saltcoats | KA21 | Ardrossan | 7 h 02 min |
| Stewarton | KA3 | Kilmarnock | 7 h 01 min |
| Troon | KA10 | Prestwick | 7 h 03 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.
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.
Can a heat pump work with my existing radiators?
Often, yes, especially with a high-temperature unit. Standard heat pumps run most efficiently at 35–50°C, so some radiators may be too small at those temperatures. A high-temperature unit can run at around 65–75°C, so existing radiators can usually heat rooms much as they do with a boiler, at a cost in efficiency. The survey checks every radiator against its room's heat loss.