Replacing a gas boiler with a heat pump means removing the boiler and installing an air-to-water heat pump that heats your radiators and a stored hot water cylinder instead. Most UK homes heat with mains gas, so this is the switch many households are weighing up, and the existing radiators and pipework can often be reused with some changes. What needs most planning depends on the type of boiler you have now.
Semi-detached and terraced houses in the Scottish Borders often have an airing cupboard that can be reused for a heat pump cylinder. Rear gardens and side returns in the Scottish Borders usually offer a sensible spot for the outdoor unit, checked for airflow and neighbours. Installers in the Scottish Borders take out the old boiler and flue and seal the wall opening as part of the job.
Who it suits
- Combi owners who can find space for a hot water cylinder
- System or regular boiler homes with an existing airing cupboard
- Households ready to give up gas entirely and drop the standing charge
- Boilers that are old, unreliable or due for replacement
Grants and rules for heat pumps in Scotland
The Boiler Upgrade Scheme does not apply in Scotland. Instead, homeowners in the Scottish Borders 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.
Gas boiler to heat pump prices in the Scottish Borders
The ranges below are typical installed prices for homes in the Scottish Borders, including VAT. A survey sets the exact figure, because two similar-looking houses in the Scottish Borders can need quite different radiators and pipework.
| Home | Typical size | Installed guide price |
|---|---|---|
| 1–2 bedroom flat or small terrace | 4–5 kW | £9,700–£12,750 |
| 2–3 bedroom terrace or semi | 5–7 kW | £10,700–£13,750 |
| 3 bedroom semi or small detached | 6–9 kW | £12,250–£15,800 |
| 4 bedroom detached | 8–12 kW | £14,300–£18,350 |
| 5+ bedroom or larger older house | 11–16 kW | £16,850–£22,950 |
Installed, inc VAT: unit, cylinder, controls, minor pipework and commissioning. In Scotland, Home Energy Scotland grants of up to £7,500 and interest-free loans may reduce the cost.
Towns we cover in the Scottish Borders
We cover 8 towns in the Scottish Borders for replacing a gas boiler with a heat pump. Each links to local guide prices and the grant position for Scotland.
| Town | Postcode district | Nearest town | Midwinter daylight |
|---|---|---|---|
| Duns | TD11 | Eyemouth | 7 h 00 min |
| Eyemouth | TD14 | Duns | 6 h 58 min |
| Galashiels | TD1 | Selkirk | 7 h 02 min |
| Hawick | TD9 | Selkirk | 7 h 04 min |
| Jedburgh | TD8 | Kelso | 7 h 04 min |
| Kelso | TD5 | Jedburgh | 7 h 02 min |
| Peebles | EH45 | Penicuik | 7 h 01 min |
| Selkirk | TD7 | Galashiels | 7 h 03 min |
Replacing a gas boiler with a heat pump questions
Do I need to replace the cylinder I already have?
Usually, yes. Older cylinders have a small internal coil designed for water from a boiler at around 60–70°C, and they cannot take in heat quickly enough at the lower temperatures a heat pump runs at. A heat pump cylinder has a larger coil. On its own, a cylinder supplied and fitted has a guide price of £1,200–£2,200, installed and including VAT, though it is normally part of the full system price.
Is there a grant to replace a gas boiler with a heat pump?
In England and Wales, the Boiler Upgrade Scheme gives £7,500 towards an air-to-water heat pump that replaces a gas boiler, for eligible owners of existing homes. The MCS-certified installer applies to Ofgem and deducts the grant from your quote, and Ofgem contacts you to confirm. Scotland has separate Home Energy Scotland funding, and Northern Ireland has no dedicated homeowner grant at present.
Will my hot water run out with a heat pump?
Not if the cylinder is sized properly for your household. The survey asks how many people live in the home, how many bathrooms you have and whether you prefer baths or showers, then sizes the cylinder to suit. The heat pump reheats the cylinder on a schedule, often overnight and again during the day, and an immersion heater acts as a backup.
Can a heat pump replace a combi boiler?
Yes, but you need room for a hot water cylinder, because heat pumps store hot water rather than heating it on demand. Most homes find a space in a cupboard, utility room, garage or under the stairs, and compact or combined indoor units help where space is tight. The survey measures the options first, so you know where everything will go before you accept the quote.

