Heat pump replacement means removing an existing outdoor unit, and sometimes the cylinder and controls, and fitting a new heat pump sized and set up for the home as it is now. Air source heat pumps typically last 15–20 years, so systems fitted when the technology was newer to UK homes are reaching the point where repairs become harder to justify.
New outdoor units in Northamptonshire may differ in size from the old one, so the base and position are checked at survey. Across Northamptonshire and Northamptonshire, old units are removed with their refrigerant recovered by an F-gas certified engineer. Every replacement in Northamptonshire starts with a fresh heat loss survey, not just a copy of the old unit's size.
Who it suits
- 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
- Heat pumps nearing the end of their typical life with rising repair costs
Grants and rules for heat pumps in England
In England 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), and since 28 April 2026 a valid EPC is no longer needed. The grant is applied for by the MCS-certified installer and shown as a deduction on your quote.
Heat pump replacement prices in Northamptonshire
These are guide prices including VAT. The rate for your visit in Northamptonshire is confirmed before we book it, and any repair is priced in writing before parts are ordered.
| 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 Northamptonshire
We cover 10 towns in Northamptonshire for heat pump replacement. Each links to local guide prices and the grant position for England.
| Town | Postcode district | Nearest town | Midwinter daylight |
|---|---|---|---|
| Northampton | NN1 | Wellingborough | 7 h 42 min |
| Corby | NN17 | Desborough | 7 h 39 min |
| Kettering | NN16 | Desborough | 7 h 40 min |
| Wellingborough | NN8 | Rushden | 7 h 41 min |
| Rushden | NN10 | Wellingborough | 7 h 41 min |
| Daventry | NN11 | Towcester | 7 h 42 min |
| Brackley | NN13 | Towcester | 7 h 44 min |
| Desborough | LE16 | Kettering | 7 h 40 min |
| Oundle | PE8 | Corby | 7 h 39 min |
| Towcester | NN12 | Northampton | 7 h 43 min |
Heat pump replacement questions
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.
Will a new heat pump fit where the old one was?
Sometimes. A new unit may be a different size, weight or shape and may have different clearance requirements, so the existing base and position are checked at survey. The MCS noise assessment is carried out for the new unit, and a different position may be suggested if it improves performance or reduces sound at neighbouring windows.
Can I get a grant to replace my heat pump?
Usually not. In England and Wales, the Boiler Upgrade Scheme cannot normally fund a home that has already been funded for a heat pump, and it is aimed at replacing fossil-fuel or electric heating. Your circumstances may differ, so we check eligibility before quoting. In Scotland, check Home Energy Scotland's criteria. Northern Ireland has no dedicated grant at present.
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.

