New boiler · fixed price
A new boiler, fixed price — fitted by a local team who turn up and tidy up.
A real price range in 60 seconds. Fitted in a day. Every job documented.
No surprises, promise
See your range in sixty seconds.
What do you need?
60 seconds to a real installed range — no contact details needed.
Real boilers, real prices
The boilers we quote most.
Worcester Bosch, Vaillant and Baxi — small, typical and big homes, at more than one budget. Fitted-from prices include materials, labour, flush, filter, certification and VAT.
Worcester Bosch
Greenstar 2000
Best for: Flats & smaller homes, 1 bathroom
Worcester Bosch
Greenstar 8000 Life
Best for: 3-bed homes wanting the premium range
Main (by Baxi)
Main Eco Compact
Best for: Flats & smaller homes, 1 bathroom
Why these brands? We fit ranges our engineers know deeply — Worcester Bosch, Vaillant and Baxi — and recommend by what suits your home, not the invoice. Here's the full range and the thinking.
Install day, plainly
What actually happens on the day.
A like-for-like combi swap is one day, start to finish. Conversions run two to three. Either way, the day looks like this — in order, no mystery.
- 1We arrive when we said. Confirmed slot, a text when we're 30 minutes out, dust sheets down before a single tool comes out.
- 2Old boiler out. Drained, disconnected, removed — and it leaves with us for responsible disposal. No rusting hulk in your front garden.
- 3System cleaned properly. A full flush to shift the sludge that kills new boilers early — especially worth doing round here, where hard water and older systems gang up on heat exchangers.
- 4New boiler in, flue sorted. Mounted, piped, gas-tightness tested, flue run and terminated to regulation — checked, not assumed.
- 5Filter, controls, commissioning. Magnetic filter fitted, controls paired and explained, combustion checked with an analyser and recorded on the Benchmark certificate.
- 6Handover, paperwork, tidy-up. We register the boiler with Gas Safe and the manufacturer, walk you through everything, and leave the place cleaner than we found it.
The quote, honestly
How the fixed price works.
1 · The calculator gives you a range. Anonymous, sixty seconds, no phone number ransom. It's an honest range for a typical installation — not a teaser figure that doubles later.
2 · A free survey fixes the number. We check the things a website can't: your mains flow and pressure, the gas run, the flue route, the state of the system. Then one written price — materials, labour and VAT.
3 · The price doesn't move. Once it's in writing, that's the invoice. If something genuinely unforeseeable turns up mid-job, we stop and talk to you before anything changes — never a surprise line item at the end.
Certified, insured, documented
Gas work is legally restricted to Gas Safe registered engineers — every Datum boiler installation is carried out by Gas Safe registered engineers, notified to Building Control, and recorded on the Benchmark certificate. Ask to see the registration card; a proper engineer expects you to.
What's included
- New boiler + flue, supplied and fitted
- Full system flush (not a quick rinse)
- Magnetic system filter fitted as standard
- Controls set up and explained
- Making good — we leave it tidy
- Gas Safe certification + Building Regs notification
- Manufacturer warranty registered for you
- Full handover so you know how it works
What's not
- Rare extras (e.g. failed pipework discovered mid-job) — flagged honestly before we start, never sprung on you
Why not a faceless online quote?
The big online installers can't come back next winter. We can — we're local, we answer, and we stand behind the work. Same upfront pricing, plus a team you'll actually see again.
The warranty, in years
Every boiler we fit carries the manufacturer's warranty for that model — on current Worcester Bosch, Vaillant and Baxi ranges that runs to a decade or more at the top end, depending on the boiler, the filter and the installer's accreditation. Your exact warranty is stated in writing on your quote, in years, before you commit — we register it for you, and an annual service keeps it valid.
Local knowledge
Boilers in Herts & North London homes.
Hard water & limescale
Hertfordshire and North London sit on chalk — the water here is genuinely hard, and limescale is what quietly kills combi heat exchangers. It's why our installs include a proper flush and a magnetic filter, and why we'll talk to you about scale protection on the hot-water side rather than let the new boiler fight the same battle the old one lost.
Victorian terraces & microbore
Plenty of local terraces were retrofitted decades ago with 8–10mm microbore pipework. It flushes differently, it restricts flow to far radiators, and a powerful new boiler on tired microbore disappoints. We check the pipework at the survey and price honestly — including when the right answer is upgrading a run or two.
Low mains pressure
A combi is only as good as the water main feeding it — and parts of the patch, especially older streets, run weak incoming flow. We measure your actual flow rate and pressure at the survey. If a combi would leave your shower feeble, we'll say so and quote a system boiler with a cylinder instead.
Conservation areas & flues
Flue position is regulated everywhere — distances from windows, boundaries and neighbours — but conservation streets in St Albans and Harpenden add rules about what can show on the front elevation. We plan the flue route at the survey, not on the day, so the quote already reflects it.
Your questions, answered
How long does a boiler installation take?↓
A like-for-like combi swap is usually one day: old boiler out, new one in, system flushed, controls set, full handover — and we tidy up properly before we leave. Conversions (like system-to-combi) run two to three days.
How much does a new boiler cost in Hertfordshire?↓
A typical like-for-like combi swap runs £2,310–£3,010 installed, including materials, labour and VAT. A conversion (e.g. system to combi) is more, typically £3,200–£4,300. Use the calculator above for your range, then a free survey fixes the exact price — which doesn't change afterwards.
Which boiler brands do you fit?↓
Worcester Bosch, Vaillant and Baxi — ranges we know inside out — and we recommend what genuinely suits your home and budget, including when the cheaper option is the right one. Where a job calls for something different, we'll say so. Warranty terms are confirmed in writing on your quote.
Do I need a power flush with a new boiler?↓
Every install includes a full system flush — it's not an optional extra, because fitting a clean boiler to a dirty system is how warranties get refused and heat exchangers die young. If your system is badly sludged (cold-bottomed radiators are the tell), we'll tell you before we price, not after.
Will a new combi work with my water pressure?↓
That's exactly what the free survey measures. Parts of Herts and North London run low incoming mains flow, and a combi on a weak main means a disappointing shower. If that's your street, we'll tell you straight and quote the setup that will actually work — even when it's not the cheapest one.
Do you take the old boiler away?↓
Yes — removal and responsible disposal of the old boiler is part of the job, along with certification, Building Regs notification and registration of the new one.
Is your work certified?↓
Gas work is legally restricted to Gas Safe registered engineers, and every Datum installation is carried out by one — with the combustion figures recorded, Building Control notified and the Benchmark certificate completed. You're welcome to see the registration card before work starts.
Before you decide
The boiler questions, answered properly.
Ready for a real price?
Sixty seconds to a range, one free survey to a fixed price.