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 County Down can compare a high-temperature unit with upsizing a few radiators, for homes anywhere in County Down. In County Down, rooms with large bay windows are often the ones where radiator output is checked most carefully. Older homes around County Down often need a discreet unit position, such as a rear courtyard, which the survey looks for first.
Who it suits
- Homes with microbore pipework that would be disruptive to replace
- Period and listed homes where the radiators are part of the character
- Owners who want fewer changes inside the house
- Rooms with no wall space for a larger radiator
Grants and rules for heat pumps in Northern Ireland
The Boiler Upgrade Scheme covers England and Wales only, and there is currently no dedicated heat pump grant for homeowners in Northern Ireland. Our quote for a home in County Down is therefore shown without a grant deduction; if support becomes available we will tell you how it applies.
There is no VAT on installing a heat pump in Northern Ireland until 31 March 2027, the same as in Great Britain. Planning and building control here follow Northern Ireland's own rules, so the survey checks the unit position against them.
High-temperature heat pumps prices in County Down
Here are typical prices for high-temperature heat pumps in County Down, 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 | £9,200–£12,150 |
| 2–3 bedroom terrace or semi | 5–7 kW | £10,200–£13,100 |
| 3 bedroom semi or small detached | 6–9 kW | £11,650–£15,050 |
| 4 bedroom detached | 8–12 kW | £13,600–£17,450 |
| 5+ bedroom or larger older house | 11–16 kW | £16,000–£21,850 |
Installed, inc VAT: unit, cylinder, controls, minor pipework and commissioning. A high-temperature unit typically adds £1,500–£3,000. No dedicated heat pump grant currently applies in Northern Ireland.
Towns we cover in County Down
We cover 13 towns in County Down for high-temperature heat pumps. Each links to local guide prices and the grant position for Northern Ireland.
| Town | Postcode district | Nearest town | Midwinter daylight |
|---|---|---|---|
| Bangor (County Down) | BT20 | Newtownards | 7 h 14 min |
| Newtownards | BT23 | Comber | 7 h 15 min |
| Newry | BT35 | Warrenpoint | 7 h 20 min |
| Banbridge | BT32 | Dromore | 7 h 18 min |
| Ballynahinch | BT24 | Downpatrick | 7 h 17 min |
| Comber | BT23 | Newtownards | 7 h 15 min |
| Donaghadee | BT21 | Bangor (County Down) | 7 h 14 min |
| Downpatrick | BT30 | Ballynahinch | 7 h 18 min |
| Dromore | BT25 | Banbridge | 7 h 17 min |
| Holywood | BT18 | Newtownabbey | 7 h 14 min |
| Kilkeel | BT34 | Warrenpoint | 7 h 21 min |
| Newcastle | BT33 | Downpatrick | 7 h 20 min |
| Warrenpoint | BT34 | Newry | 7 h 21 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.
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.
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.