Heat Pump: Repair or Replace? (2026 cost comparison)
The rule of thumb, from Consumer Reports: don't spend more than 50% of a comparable new unit on fixing the old one. For a heat pump, that 50% line is about £3,500–£7,500 — a new unit runs £7,000–£15,000 and typically lasts 15–20 years. If a repair quote lands under that line and the heat pump is not yet past its expected life, repair usually wins. Reviewed July 2026.
Repair vs. replace, side by side Estimated
| Cost | Estimated range |
|---|---|
| Typical repair (this heat pump, all faults we price) | £50–£3,500 |
| New heat pump (unit only) | £7,000–£15,000 |
| The 50% line half a comparable new unit | £3,500–£7,500 |
Repair: min–max of every heat pump fault we price (sources on each linked problem page) · New unit: GreenMatch, MyJobQuote · Lifespan 15–20 years: Hive, Hometree · 50% rule: Better Call Wes · Reviewed July 2026 · Estimated
Age × repair-cost worksheet Estimated
Find your heat pump's age down the side and your repair quote across the top. The cell is the way the 50% rule points — Estimated guidance, not advice.
| Age of unit | Repair < 30% of a new heat pumpunder £2,100–£4,500 | Repair 30–50%£2,100–£4,500 – £3,500–£7,500 | Repair > 50%over £3,500–£7,500 |
|---|---|---|---|
| Under 9 years first half of typical life | Repair likely | Repair likely | Compare quotes |
| 9–20 years second half, under typical lifespan | Repair likely | Compare quotes | Replace likely |
| Over 20 years at or beyond typical lifespan | Compare quotes | Replace likely | Replace likely |
How this is built: we apply the 50% rule (Better Call Wes) — spend no more than half a comparable new unit's cost on a repair — with its lifespan corollary (replacement is favored once the unit is past the midpoint of its expected life and the quote tops 50%). Columns are your repair quote as a share of a new heat pump (£7,000–£15,000); the £3,500–£7,500 and £2,100–£4,500 thresholds are just 50% and 30% of that range. Rows use the midpoint of the expected life (about 9 years — halfway through a typical 18-year lifespan) and the top of the sourced 15–20 years range (20 years). Nothing here is a per-unit price or a recommendation — it is a transparent reading of the rule.
Air source is the relevant UK domestic case. The 15-20 headline is used because two UK sources agree on it as the typical band; Hometree's 10-20 lower bound is disclosed above rather than silently narrowed. Hive lists the replacement triggers as: age approaching or exceeding 15-20 years, repairs needed more than once or twice a year, rising bills despite maintenance, inconsistent temperatures, and unusual noises or odours; and recommends annual professional servicing with filter changes every 1-3 months. Ground-source figures are noted for context only — this taxonomy has no ground-source type, and the ground-source range must not be presented as the air-source one. Refrigerant-circuit repairs on a heat pump fall under the F-Gas gate described in the heuristics. No US heat pump lifespan has been carried over. The new_unit_gbp range GBP 7,000-15,000 is the bundled supplied-and-installed cost of an air source heat pump BEFORE any Boiler Upgrade Scheme grant (currently GBP 7,500 in England and Wales, which both cited sources note can cut the net cost substantially); two independent UK sources fetched live 2026-07-22 (GreenMatch, MyJobQuote) agree on the GBP 7,000 floor and both cite GBP 15,000 as the larger/complex-install ceiling. install_delivery_gbp is null on the bundled-total convention — GreenMatch's separable labour-only figure (GBP 3,500-6,000) is recorded in its source note rather than shipped as a split.
One more thing before you replace
A newer heat pump can cut energy and water use, which shifts the math on an older unit even when a repair is cheap: ENERGY STAR notes clothes washers over ~10 years and refrigerators over ~15 years are common efficiency-driven replacements.
Energy note: · Reviewed July 2026 · Estimated · Informational only
Price the repair first
Before you decide, get the likely repair figure for the exact fault — each page localizes to your metro:
- Full heat pump cost guide
- Not heating
- Not cooling
- Stuck in defrost / frozen outdoor unit
- Reversing valve replacement
- Defrost control board replacement
- Capacitor replacement
- Refrigerant leak repair / recharge
- Compressor replacement
- Outdoor fan motor replacement
- Short cycling (turns on and off)
Estimated ranges — see the methodology for how we build the repair figures and their named sources. This page is informational and is not repair, purchasing, or financial advice.
Reviewed by a Red Seal–certified appliance technician who also holds a Technical Safety BC gas ticket (Gas-C) and an ODS/halocarbon refrigerant ticket (CFC/HCFC/HFC).