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.
Period houses in Argyll and Bute with original cast-iron radiators may suit a high-temperature unit that works with them. Older homes around Argyll and Bute often need a discreet unit position, such as a rear courtyard, which the survey looks for first. In Argyll and Bute, rooms with large bay windows are often the ones where radiator output is checked most carefully.
Who it suits
- Homes with microbore pipework that would be disruptive to replace
- Older homes where insulation improvements are limited
- Period and listed homes where the radiators are part of the character
- Owners who want fewer changes inside the house
Grants and rules for heat pumps in Scotland
The Boiler Upgrade Scheme does not apply in Scotland. Instead, homeowners in Argyll and Bute 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 Argyll and Bute
These are guide prices for Argyll and Bute, installed and including VAT. Your final price is fixed in a written quote after the survey and depends on the heat loss of the house, the radiators that need changing and where the unit goes.
| Home | Typical size | Installed guide price |
|---|---|---|
| 1–2 bedroom flat or small terrace | 4–5 kW | £10,250–£13,500 |
| 2–3 bedroom terrace or semi | 5–7 kW | £11,350–£14,600 |
| 3 bedroom semi or small detached | 6–9 kW | £12,950–£16,750 |
| 4 bedroom detached | 8–12 kW | £15,100–£19,450 |
| 5+ bedroom or larger older house | 11–16 kW | £17,800–£24,300 |
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 Argyll and Bute
We cover 6 towns in Argyll and Bute for high-temperature heat pumps. Each links to local guide prices and the grant position for Scotland.
| Town | Postcode district | Nearest town | Midwinter daylight |
|---|---|---|---|
| Campbeltown | PA28 | Girvan | 7 h 04 min |
| Dunoon | PA23 | Gourock | 6 h 57 min |
| Helensburgh | G84 | Greenock | 6 h 57 min |
| Lochgilphead | PA31 | Dunoon | 6 h 56 min |
| Oban | PA34 | Lochgilphead | 6 h 51 min |
| Rothesay | PA20 | – | 6 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.
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.
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.
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.

