A new boiler is one of the bigger investments a homeowner makes — typically £2,500 to £4,500 fitted in West London, depending on the unit, the property and what associated work needs doing. Done right, a new boiler will run for fifteen years or more, save several hundred pounds a year on gas bills compared with an old non-condensing unit, and rarely give you any trouble between annual services.
Done wrong — undersized, poorly flued, badly commissioned, or fitted without notification — and you could be looking at noisy operation, repeated lockouts, accelerated component wear, voided warranty, and a property that fails its next gas safety check. The boiler itself is only half the job. The other half is the engineer who fits it, sizes it, flues it, commissions it, and registers it correctly with both the manufacturer and the local authority.
There are three main types of domestic gas boiler fitted in UK homes, and the right choice depends on the size of your property, the number of bathrooms, your hot water demand, and your existing system layout.
Combi boilers are the most common choice for flats, terraces and smaller semis across Ealing. A combi heats your water on demand directly from the mains — no hot water cylinder, no cold water tank in the loft, no airing cupboard given over to a tank. Modern combis from Worcester (Greenstar 4000, 8000 Style), Vaillant (ecoTEC plus, ecoFIT) and Baxi (Duo-tec, EcoBlue) deliver excellent flow rates for kitchens and showers in homes with one or two bathrooms. The downside: if you run two showers at once, the flow rate splits between them. Best for: 1–3 bedroom homes with one bathroom and good mains water pressure.
System boilers are the right answer for larger homes with two or more bathrooms, family-sized hot water demand, and the airing cupboard space for an unvented cylinder. The boiler heats water to a stored cylinder which can then deliver mains-pressure hot water to multiple outlets simultaneously. You lose the loft tanks of a traditional setup but gain a much higher hot water capacity. Best for: 3–5 bedroom homes with two or more bathrooms.
Regular (heat-only) boilers remain in many older Ealing properties — particularly Victorian and Edwardian conversions where the existing pipework, F&E tanks and hot water cylinder make a like-for-like replacement the most cost-effective route. Regular boilers feed a separate cylinder via gravity-fed cold and feed-and-expansion tanks in the loft. They're not the modern choice, but if your existing system is sound and you want to avoid the disruption of converting to a combi or system layout, a like-for-like regular swap can make excellent sense. Best for: properties with an existing regular setup that's still working well.
David will tell you straight which type is right for your property — and equally, where there's a strong case for staying with what you've got rather than converting. The best installation is the one that matches the property and the household, not the one with the highest invoice.
Modern condensing boilers run at well over 90% efficiency. The condensing part means the boiler captures the latent heat in the water vapour produced by burning gas, which would otherwise go straight up the flue. That captured heat is recycled back into the heating return — which is why condensing boilers have a small condensate pipe running to a drain, carrying the slightly acidic water that's been wrung out of the flue gases.
Old non-condensing boilers from the 1990s and earlier typically ran at 60–70% efficiency, so the gas-bill saving from upgrading is genuinely substantial — usually £200–£400 a year for an average Ealing semi, depending on usage and the boiler being replaced. Combined with smart controls (Hive, Nest, tado, Worcester Wave) you can squeeze even more out of the system by only heating the rooms you're using when you're using them.
One of the most common mistakes in domestic boiler installation is fitting a boiler that's too big. The reasoning seems intuitive — bigger boiler, more power, never short of heat. In practice, an oversized boiler short-cycles: it fires up to a high temperature, hits the thermostat almost immediately, shuts off, and repeats. Each cycle wears the components, increases NOx emissions, and ironically reduces overall efficiency below that of a correctly sized smaller unit.
David sizes every boiler properly — typically by calculating heat loss room by room (or using a sensible whole-house estimate based on property age, insulation level and floor area) and matching the kW output to actual demand. For an average 3-bed Ealing semi, that's usually a 24–28kW combi or a 15–18kW heat output system boiler. Bigger isn't better. Right is better.
Flue routing matters too. Building regulations specify minimum distances from openings (windows, doors, vents) for the flue terminal — typically 300mm from a window, 1.2m from a boundary, and so on. Some properties (especially Edwardian conversions in Acton and Ealing) need vertical flues through the roof rather than horizontal flues through the wall. David will work out the right route on the survey and price it accordingly.
Every boiler installation David quotes for is fully inclusive. There are no optional extras hidden in the small print, no ‘starts at’ pricing, and no per-hour add-ons. The fixed price covers the lot.
Included as standard on every install: the new boiler unit (Worcester, Vaillant, Baxi or Ideal as agreed), the horizontal or vertical flue and any extensions needed, the room thermostat (basic or smart, your choice), a magnetic system filter (Adey MagnaClean, Fernox TF1 or equivalent), a full chemical system flush, the removal and responsible disposal of your old boiler, all gas testing and pressure testing, full commissioning to manufacturer specification, warranty registration with the manufacturer, building-regulations notification through the Gas Safe Register within 30 days, and the Benchmark commissioning checklist filled in and handed over to you on completion.
If your install needs anything additional — a power flush, an upgraded gas supply pipe, a new condensate route, fresh radiators, or system rebalancing — it'll be on the written quote before David starts, so you know exactly what you're paying.
By law, every domestic gas installation in the UK must be carried out by an engineer registered with the Gas Safe Register — the official body that replaced CORGI in 2009. David is fully Gas Safe registered and carries his ID card on every visit. Ask to see it before any work starts. The card has a photo, his registration number, and an expiry date — and you can verify the registration directly on the gassaferegister.co.uk website by entering the number.
Using an unregistered engineer for any gas work is illegal — and dangerous. It also voids your home insurance, makes any future warranty claim impossible, and means the work won't be notified to your local authority. Every boiler David fits is registered with both the manufacturer and Gas Safe within 30 days of completion, so your install shows up on the official record from the day it goes in.
For a like-for-like combi swap in an average Ealing property, expect £2,500–£3,500 fitted including filter, flush, controls and warranty registration. Worcester Bosch and Vaillant sit at the top of that range; Baxi and Ideal at the bottom. System boiler installs (with cylinder work) typically run £3,500–£5,500. Full conversions — combi to system, regular to combi — start around £4,000 and depend heavily on pipework changes. David always gives a fixed written quote after the survey so you know the exact number before committing. The full gas-side service list David covers: boiler servicing, boiler repair, central heating installation, central heating repair, gas safety checks, gas leak detection, gas cooker installation, gas fire servicing and power flushing — all Gas Safe registered, all run from the same Ealing base.
A like-for-like combi swap with no surprises is usually a one-day job — engineer arrives 8am, hot water back on by mid-afternoon, full system tested and commissioned by end of day. System boiler installs are 1–2 days depending on cylinder access. Conversions (e.g. regular to combi) typically run 2–3 days because of pipework, tank removal and electrical changes. David tells you the expected schedule on the quote, so there are no surprises.
Manufacturer warranties on new boilers are now substantial — Worcester Bosch offer up to 12 years on the Greenstar 8000 range when fitted by an accredited installer; Vaillant offer up to 10 years on the ecoTEC plus; Baxi offer 7–10 years depending on model; Ideal offer 7–12 years on the Logic and Vogue ranges. The warranty starts the day David registers the install with the manufacturer, which happens automatically within 30 days of commissioning. You'll get the registration confirmation by email.
Not always. If your existing system is reasonably clean — checked by inspecting the existing magnetic filter, the colour of system water, and how warm the radiators run top-to-bottom — a chemical flush combined with a fresh magnetic filter is enough. If the system is heavily sludged (cold spots on radiators, old steel rads on a system that's never been flushed, visible black water on bleed) then a full power flush is the right call. Skipping a needed flush voids most manufacturer warranties — David will tell you straight which one your system needs. Other plumbing work Clive covers from the same Ealing base: emergency plumbing, drain unblocking, tap and outlet installation, toilet installation, white goods plumbing, kitchen plumbing, radiator installation and bathroom installation.
Yes — removal and responsible disposal of your old boiler is included in every quote. David takes the old unit away, drains it down for safe transport, and disposes of it through licensed scrap and waste streams. You don't need to do anything beyond clearing space around the old boiler before the install day.
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For a free, no-obligation quote on a new boiler installation anywhere in boiler installation in Ealing, boiler installation in Acton, boiler installation in Hanwell, boiler installation in Greenford, Northolt, Perivale, Southall, boiler installation in West Ealing, Park Royal, boiler installation in Pitshanger, Brentham, North Ealing, boiler installation in South Ealing or anywhere else across the W postcodes — give David a ring directly. He'll answer the phone himself, take a few minutes to understand your property and your existing setup, and book a free survey at a time that works for you.
David also covers boiler installation across the rest of the borough — boiler installation in Boston Manor, boiler installation in Brentford, boiler installation in Ealing Common and boiler installation in Northfields — all served from the same Ealing base, same Gas Safe registered engineer, same fixed-price quotes.
Quotes are always free, always written, and always honour the price you're quoted. If David doesn't think a new boiler is the right call — for example, if your existing unit has years left in it and just needs a service — he'll tell you that openly rather than pushing an install you don't need.