Vaillant is a solid choice for a UK gas boiler — the German manufacturer's ecoTEC Plus range covers combi, system and heat-only (open vent) formats from 12kW to 38kW, with a standard 5-year parts-and-labour guarantee that stretches to 10 years when fitted by a Vaillant Advance installer with a protection kit. It sits alongside Worcester Bosch and Ideal as one of the three brands UK heating engineers most commonly recommend. The main caveat: Vaillant's own smart control, sensoAPP, has been discontinued in favour of the newer myVAILLANT app and myVAILLANT connect gateway, so check which control comes with your quote. For most UK homes an ecoTEC Plus combi in the 25–35kW range, installed by a Vaillant Advance installer for the longer guarantee, is the safest buy.
What boilers does Vaillant sell in the UK?
Vaillant's current UK residential range is built around the ecoTEC Plus, available as a combi boiler (heating and hot water from one unit, no cylinder needed), a system boiler (works with a hot water cylinder, suited to homes with multiple bathrooms), or a heat-only/open vent boiler (for older systems with a header tank). Combi outputs run up to 38kW, while system and open vent models are offered in a wider spread of sizes from 12kW up to 37kW, letting an installer match output to the property's heat loss and hot water demand rather than over-sizing the boiler.
Vaillant also sells the aroTHERM plus air source heat pump range for homes moving away from gas — see our Vaillant aroTHERM plus review if you're comparing a heat pump against a like-for-like gas boiler swap.
How much does a Vaillant boiler cost installed?
Installed prices for a Vaillant ecoTEC Plus combi depend heavily on output size and whether the installation is a straight swap or involves moving the boiler or upgrading pipework. As a general guide, Which?'s boiler cost research puts a typical UK gas combi installation — across all major brands — in the low-to-mid thousands, with larger outputs and system/heat-only conversions at the top end. Get at least two quotes from Gas Safe registered installers, and ask each one to itemise the boiler-only price separately from labour, so you can compare like for like.
| Format | Typical output range | Best suited to |
|---|---|---|
| ecoTEC Plus combi | Up to 38kW | Flats and houses with one bathroom, no cylinder space |
| ecoTEC Plus system | 12–37kW | Homes with a hot water cylinder and multiple bathrooms |
| ecoTEC Plus open vent (heat-only) | 12–35kW | Older systems with a loft header tank |
How long is the Vaillant boiler warranty?
Vaillant's standard guarantee is 5 years parts and labour on ecoTEC Plus boilers, provided the appliance is registered within 30 days of installation and serviced annually by a Gas Safe registered engineer. That period extends to 7 years through standard manufacturer registration on eligible models, and up to 10 years when the boiler is installed by a member of the Vaillant Advance installer scheme together with Vaillant's magnetic boiler protection kit. If a quote doesn't mention Advance installer status, ask directly — it's the difference between a 5-year and a 10-year guarantee on the same boiler.
Can you control a Vaillant boiler with Home Assistant?
Not directly out of the box, but there are two practical routes in. Vaillant's own myVAILLANT connect gateway pairs with eBUS-compatible appliances (2006 onwards) for app control and, with a compatible smart control, Apple HomeKit voice commands — useful if your smart home is HomeKit-based. For Home Assistant specifically, community-maintained integrations that talk to the myVAILLANT/sensoAPP cloud API exist on GitHub and are documented on the Home Assistant Community forum, giving climate and hot water control plus sensor data inside HA. Vaillant boilers use Vaillant's own eBus protocol rather than the open OpenTherm standard, so a stock OpenTherm gateway won't talk to an ecoTEC Plus without an eBus-to-OpenTherm adapter — the community myVAILLANT integration is the more direct route for most owners.
Vaillant vs Worcester Bosch vs Ideal: how does it compare?
All three are among the UK's most-installed boiler brands and offer broadly comparable reliability and parts availability. Vaillant's standout is its warranty ceiling — up to 10 years via Advance installers, matching Worcester Bosch's top-tier cover — while Ideal has traditionally positioned itself as the more budget-friendly of the three. Read our Worcester Bosch boiler review and Ideal boiler review for the same breakdown on those brands, and our best combi boiler UK round-up if you're comparing across brands rather than settling on one.
Which Vaillant model should you buy?
For a typical UK semi or terrace with one bathroom, an ecoTEC Plus combi in the 25–30kW range covers most heating and hot water demand without oversizing. Larger homes with two or more bathrooms, or a household that showers at the same time as running a bath, should look at an ecoTEC Plus system boiler paired with an unvented cylinder instead. Whichever format you choose, prioritise the installer's Advance accreditation over a slightly cheaper quote from a non-Advance installer — the extended guarantee is worth more over a boiler's working life than the difference in fitting cost.
