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.
Many gas-heated homes in Dyfed have a combi boiler in the kitchen, so the survey starts by finding the right place for a cylinder. Installers in Dyfed take out the old boiler and flue and seal the wall opening as part of the job. Rear gardens and side returns in Dyfed usually offer a sensible spot for the outdoor unit, checked for airflow and neighbours.
Who it suits
- Combi owners who can find space for a hot water cylinder
- Boilers that are old, unreliable or due for replacement
- Households ready to give up gas entirely and drop the standing charge
- System or regular boiler homes with an existing airing cupboard
Grants and rules for heat pumps in Wales
Homes in Dyfed can use the Boiler Upgrade Scheme, which applies in Wales as well as England: £7,500 towards an air source heat pump, or £9,000 when it replaces oil or LPG heating for installations from 21 July 2026 to 31 March 2027. The MCS-certified installer named in your quote applies and deducts the grant.
There is no VAT on installing a heat pump anywhere in the UK, Wales included, until 31 March 2027. Planning rules for heat pumps in Wales are set by the Welsh Government and differ from England's, so the surveyor checks the unit position against them.
Gas boiler to heat pump prices in Dyfed
The ranges below are typical installed prices for homes in Dyfed, including VAT. A survey sets the exact figure, because two similar-looking houses in Dyfed 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 | £9,500–£12,500 | £2,000–£5,000 |
| 2–3 bedroom terrace or semi | 5–7 kW | £10,500–£13,500 | £3,000–£6,000 |
| 3 bedroom semi or small detached | 6–9 kW | £12,000–£15,500 | £4,500–£8,000 |
| 4 bedroom detached | 8–12 kW | £14,000–£18,000 | £6,500–£10,500 |
| 5+ bedroom or larger older house | 11–16 kW | £16,500–£22,500 | £9,000–£15,000 |
Installed, inc VAT: unit, cylinder, controls, minor pipework and commissioning.
Towns we cover in Dyfed
We cover 11 towns in Dyfed for replacing a gas boiler with a heat pump. Each links to local guide prices and the grant position for Wales.
| Town | Postcode district | Nearest town | Midwinter daylight |
|---|---|---|---|
| Llanelli | SA15 | Gorseinon | 7 h 48 min |
| Ammanford | SA18 | Pontardawe | 7 h 47 min |
| Aberystwyth | SY23 | Machynlleth | 7 h 40 min |
| Carmarthen | SA31 | Llanelli | 7 h 46 min |
| Cardigan | SA43 | Fishguard | 7 h 44 min |
| Fishguard | SA65 | Haverfordwest | 7 h 44 min |
| Haverfordwest | SA61 | Milford Haven | 7 h 46 min |
| Lampeter | SA48 | Carmarthen | 7 h 43 min |
| Milford Haven | SA73 | Pembroke Dock | 7 h 47 min |
| Pembroke Dock | SA72 | Milford Haven | 7 h 48 min |
| Tenby | SA70 | Pembroke Dock | 7 h 48 min |
Replacing a gas boiler with a heat pump questions
What if my gas boiler is fairly new?
A newer boiler can still be replaced, but the timing is worth weighing. Some owners switch when the boiler needs a major repair; others prefer to plan the change for a convenient time. Across the UK, heat pump installation is zero-rated for VAT until 31 March 2027. A hybrid system, which keeps the boiler alongside a heat pump, is another option, though it is not eligible for the Boiler Upgrade Scheme in England and Wales.
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.
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.

