- Area
- Mid Glamorgan
- Postcode district
- CF83
- Nation
- Wales
- Guide price
- From £9,500 inc VAT
- Survey
- Free for installation enquiries
Before you book: replacing a gas boiler with a heat pump in Caerphilly
In Caerphilly, as anywhere in the UK, the heat pumps that perform well are the ones designed around low flow temperatures and sized from a proper heat loss calculation.
Many gas-heated homes in Caerphilly have a combi boiler in the kitchen, so the survey starts by finding the right place for a cylinder. Installers in Caerphilly take out the old boiler and flue and seal the wall opening as part of the job.
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.
- Homes in England and Wales eligible for the Boiler Upgrade Scheme
- Boilers that are old, unreliable or due for replacement
- Combi owners who can find space for a hot water cylinder
What's included
- Removal of the gas boiler, flue and any loft tanks
- Commissioning, MCS certificate and grant application in England and Wales where eligible
- Heat pump cylinder, outdoor unit and weather compensation controls
- Capping of the gas pipe at the boiler position where you are giving up gas
- Free survey with heat loss calculation and cylinder siting
Rear gardens and side returns in Caerphilly 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 Caerphilly 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.
What to budget for replacing a gas boiler with a heat pump in Caerphilly
Here are typical prices for replacing a gas boiler with a heat pump in Mid Glamorgan, 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 | 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.
Short winter days in Caerphilly and what they mean
On the shortest day Caerphilly gets about 7 hours 49 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.
What happens after you enquire in Caerphilly?
- Start online with a guide price or call us.
- A home survey in Caerphilly 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 Caerphilly: questions
Do you cover Pontypridd as well as Caerphilly?
Yes. We arrange surveys and installation in Pontypridd, which is about 6 miles west of Caerphilly, and across Mid Glamorgan.
What size heat pump does a Caerphilly home need?
It depends on the heat loss, not the postcode. As a rough guide, a 3 bedroom semi often needs 6–9 kW, but the room-by-room survey sets the actual size for your Caerphilly home.
Can you service a heat pump in Caerphilly that someone else installed?
Yes. We arrange servicing and repairs for most air source heat pumps in Caerphilly, whoever fitted them. Tell us the make and model when you book.
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.