- Area
- South Glamorgan
- Postcode district
- CF10
- Nation
- Wales
- Guide price
- From £9,500 inc VAT
- Survey
- Free for installation enquiries
What to know about replacing a gas boiler with a heat pump in Cardiff
Homes around Cardiff range from older terraces to newer estates, and each needs a different design. That is why we survey before we quote.
Installers in Cardiff take out the old boiler and flue and seal the wall opening as part of the job. Households across South Glamorgan moving off gas can have a survey in Cardiff that compares running costs on realistic assumptions.
Moving from mains gas to a heat pump means finding cylinder space, deciding what happens to the gas supply and comparing running costs on realistic assumptions.
- System or regular boiler homes with an existing airing cupboard
- Households ready to give up gas entirely and drop the standing charge
- Combi owners who can find space for a hot water cylinder
What's included
- Heat pump cylinder, outdoor unit and weather compensation controls
- Removal of the gas boiler, flue and any loft tanks
- Commissioning, MCS certificate and grant application in England and Wales where eligible
- System flush and radiator upgrades where the design calls for them
- Capping of the gas pipe at the boiler position where you are giving up gas
Rear gardens and side returns in Cardiff usually offer a sensible spot for the outdoor unit, checked for airflow and neighbours.
Grants and rules for heat pumps in Wales
In Wales the Boiler Upgrade Scheme gives £7,500 towards an air source heat pump (£9,000 if it replaces oil or LPG, from 21 July 2026 to 31 March 2027; £2,500 for air-to-air). The MCS-certified installer named in your quote applies to Ofgem for you, and the grant comes off your Cardiff quote.
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 Cardiff
The ranges below are typical installed prices for homes in South Glamorgan, including VAT. A survey sets the exact figure, because two similar-looking houses in Cardiff 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.
Winter daylight and heating in Cardiff
On the shortest day Cardiff gets about 7 hours 50 minutes of daylight, and the winter sun reaches only around 15° above the horizon at noon. Winters this far south are milder than in most of the UK, which helps a heat pump run at low flow temperatures for much of the season.
The steps for replacing a gas boiler with a heat pump in Cardiff
- Start online with a guide price or call us.
- A home survey in Cardiff gives us the room-by-room heat loss.
- Your written quote sets out the design, the price and the grant position where you live.
- Installation is booked for dates that suit you; most homes take 2–4 days on site.
- After commissioning you get a handover of the controls and settings, plus the certificates.
Replacing a gas boiler with a heat pump in Cardiff: questions
Where would the outdoor unit go on a Cardiff house?
Usually at the side or rear, on a level base with space around it for airflow and servicing, away from bedroom windows where possible. The surveyor checks positions at your Cardiff home.
Do I need new radiators for a heat pump in Cardiff?
Often some, not all. Heat pumps run best at lower water temperatures, so rooms with small radiators may need larger ones. The survey of your Cardiff home gives a room-by-room list.
How soon can you survey a home in Cardiff?
Survey dates depend on how busy installers are in South Glamorgan. We offer the next available dates when you enquire and confirm them in writing.
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.
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.