Replacing an old outdoor unit like-for-like has a guide price of £6,000–£9,500, installed and including VAT. Where the system needs re-sizing or other upgrades, the written quote sets out each item. Grant funding rarely applies to replacements, because the Boiler Upgrade Scheme in England and Wales cannot usually fund a home already funded for a heat pump, so we check eligibility before quoting.
Across Gwynedd and Gwynedd, old units are removed with their refrigerant recovered by an F-gas certified engineer. Every replacement in Gwynedd starts with a fresh heat loss survey, not just a copy of the old unit's size. New outdoor units in Gwynedd may differ in size from the old one, so the base and position are checked at survey.
Who it suits
- Heat pumps nearing the end of their typical life with rising repair costs
- Units that have failed with a major fault, such as a compressor failure
- Oversized systems that short cycle and cost more to run than expected
- Older units where parts are becoming hard to source
Grants and rules for heat pumps in Wales
Homes in Gwynedd 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.
Heat pump replacement prices in Gwynedd
Guide prices for Gwynedd, including VAT. We agree the visit rate before anyone attends, so there are no surprises on the day.
| Work | Installed guide price |
|---|---|
| Replacing an old outdoor unit like-for-like | £6,000–£9,500 |
| Full system replacement, 2–3 bedroom terrace or semi | £10,500–£13,500 |
| Full system replacement, 3 bedroom semi or small detached | £12,000–£15,500 |
| Full system replacement, 4 bedroom detached | £14,000–£18,000 |
Installed, inc VAT. Grant funding rarely applies to replacing a heat pump, so these prices are shown without any deduction; we check eligibility at survey.
Towns we cover in Gwynedd
We cover 9 towns in Gwynedd for heat pump replacement. Each links to local guide prices and the grant position for Wales.
| Town | Postcode district | Nearest town | Midwinter daylight |
|---|---|---|---|
| Bangor (Gwynedd) | LL59 | Beaumaris | 7 h 31 min |
| Bala | LL23 | Dolgellau | 7 h 35 min |
| Beaumaris | LL58 | Bangor (Gwynedd) | 7 h 31 min |
| Caernarfon | LL55 | Llangefni | 7 h 32 min |
| Dolgellau | LL40 | Machynlleth | 7 h 36 min |
| Holyhead | LL65 | Llangefni | 7 h 30 min |
| Llangefni | LL77 | Bangor (Gwynedd) | 7 h 31 min |
| Porthmadog | LL49 | Pwllheli | 7 h 34 min |
| Pwllheli | LL53 | Porthmadog | 7 h 35 min |
Heat pump replacement questions
How much does it cost to replace a heat pump?
Replacing an old outdoor unit like-for-like has a guide price of £6,000–£9,500, installed and including VAT. Re-sizing, a new cylinder, radiator upgrades or new controls add to that, and each is itemised in your written quote. The final price is fixed after a survey, once we know what the existing system needs.
What happens to my old heat pump?
The old outdoor unit is removed and disposed of responsibly. Its refrigerant is recovered first, which must be done by an F-gas certified engineer, and metals and components are recycled where facilities allow. If the old cylinder or controls are replaced too, they are removed at the same time, and pipework that is no longer needed is capped or taken out.
How long does an air source heat pump last?
Air source heat pumps typically last 15–20 years, depending on the quality of the original design, how hard the unit has worked, where it is sited and how well it has been serviced. Units that short cycle or run at high flow temperatures for years may wear sooner. Annual servicing helps components last and spots problems early.
Can I replace just the outdoor unit?
Often, yes, if the rest of the system is sound and correctly designed. The cylinder, controls and radiators can stay where they are compatible with the new unit. Some older cylinders and controllers do not work with a new heat pump, and the survey checks this. If the original design was the problem, replacing only the unit will not fix it.