UK 2026 / Reviewed October 2026
Vaillant boiler replacement cost
Germany (Remscheid), Vaillant Group
New Vaillant boilers installed from £2,519 at BOXT's published fixed prices (checked 22 October 2026). That is the floor for the smallest output in a like-for-like swap. Model-by-model prices are below.
Vaillant models, prices and warranty
Installed prices are BOXT's published fixed "from" prices, which include removal of the old boiler and the installation labour. A dash means BOXT does not list a price for that model.
| Model | Type | Installed from | Warranty |
|---|---|---|---|
| ecoFIT pure | Combi / system / open vent | £2,519 | 2 years out of the box, up to 10 with the Advance kit |
| ecoTEC plus | Combi / system / open vent | £2,849 | 5 years out of the box, up to 10 with the Advance kit |
| ecoTEC exclusive | Combi / system | - | Up to 10 years with the Advance kit |
Source: BOXT Vaillant boilers, checked 22 October 2026.
Warranty and what it depends on
Up to 10 years on ecoTEC plus, ecoTEC exclusive and ecoFIT pure (up to 45 kW) with the Advance Boiler Protection Kit, registered through Advance. Vaillant warranty terms
- The 10-year term needs the Advance Boiler Protection Kit (Vaillant's own magnetic filter and system test kit) fitted at install
- The installer must register the boiler through Vaillant's Advance scheme
- Without the kit, the out-of-the-box term applies: 5 years on ecoTEC plus, 2 years on ecoFIT pure
Frequently asked
How much does a Vaillant boiler cost installed?
BOXT, a fixed-price online installer, publishes installed prices for Vaillant boilers starting from £2,519 (checked 22 October 2026). That is the floor for the smallest output in a straightforward swap; a bigger output, a type change or a boiler move costs more. The Energy Saving Trust puts the average cost of replacing a G-rated gas boiler with an A-rated one, with radiator valves, at £3,500 in Great Britain.
What warranty does Vaillant offer?
Up to 10 years on ecoTEC plus, ecoTEC exclusive and ecoFIT pure (up to 45 kW) with the Advance Boiler Protection Kit, registered through Advance. Conditions: The 10-year term needs the Advance Boiler Protection Kit (Vaillant's own magnetic filter and system test kit) fitted at install; The installer must register the boiler through Vaillant's Advance scheme; Without the kit, the out-of-the-box term applies: 5 years on ecoTEC plus, 2 years on ecoFIT pure.
How do I find an accredited installer?
Vaillant runs its own installer search on its UK site. Separately, check any installer at gassaferegister.co.uk and ask to see their Gas Safe ID card before work starts. The manufacturer's accredited-installer status is what unlocks the longest warranty terms.
Compare against other brands on the by-brand index. Still deciding which type? cost by type.