Combi, System or Regular Boiler?
Choosing a new boiler is one of the biggest home decisions you can make — and getting it wrong can cost you money for years. The good news is that with a bit of guidance, the right choice is usually straightforward. Here's how we explain it to homeowners across Battersea, Clapham, Chelsea and SW London.
Combi Boilers
Combination boilers are by far the most popular choice in London homes, and for good reason. A combi provides both central heating and instant hot water on demand, all from a single compact unit. There's no need for a hot water cylinder or a cold water tank in the loft, which makes them ideal for flats and smaller terraced houses — exactly the kind of properties common across Battersea, Fulham and Clapham.
Best for: Flats, 1–3 bedroom homes, properties without loft space, households with one bathroom.
Consider if: You have multiple bathrooms or a large household using hot water simultaneously — a combi can struggle to meet simultaneous demand at high flow rates.
System Boilers
A system boiler works alongside a hot water cylinder, storing a tank of hot water ready for use. Unlike older gravity-fed systems, a modern system boiler delivers hot water at mains pressure, so shower performance is excellent throughout the property. This is a popular choice in larger Battersea and Chelsea houses with two or more bathrooms.
Best for: 3–5 bedroom homes, properties with multiple bathrooms, households with high hot water demand.
Regular (Heat-Only) Boilers
Regular boilers — also called heat-only or conventional boilers — are generally only recommended where an existing system already uses this configuration and a full system upgrade isn't practical. They require both a hot water cylinder and a cold water feed tank. We most commonly encounter these in older properties across SW London that haven't been updated in some time.
What to Expect on Installation Day
A standard combi boiler installation in a London property typically takes one day. Our engineers will arrive, assess the existing pipework and flue route, remove the old boiler, fit the new unit and commission it fully. We fit a magnetic system filter as standard, which protects the new boiler from sludge and debris, and we carry out a system flush beforehand.
You'll receive a Gas Safety Certificate and we'll walk you through the controls before we leave. If you have a manufacturer warranty registration to complete, we'll do that for you too.
Which Brands Do We Recommend?
We install all major brands, but our most commonly fitted boilers are Worcester Bosch and Vaillant. As a Worcester Bosch approved installer, we can offer extended manufacturer warranties — up to 10 years on eligible models — which provides real peace of mind on a significant investment.
How Much Does a New Boiler Cost in London?
Boiler installation costs vary depending on the type of boiler, the model chosen, and the complexity of the installation (for example, whether you're changing fuel type or relocating the boiler). We provide free surveys and fixed-price quotes before any work is agreed — so you'll know the full cost upfront with no surprises.
Contact us to arrange a free survey, or call us on 07773 991199 to discuss your options.
Areas We Cover for Boiler Installation
We install new boilers across Battersea, Clapham, Chelsea, Wandsworth, Fulham, Balham, Tooting, Putney, Kensington, Hammersmith, Ealing, Golders Green, Harrow, Wembley and across SW and NW London. See our boiler installation service page for more details.