New boiler quotes in
Harrow.
A-rated combi boilers from £1,800 fitted, with 10-year warranties. Free quotes from Gas-Safe installers serving Harrow and the wider Greater London area.
3 quotes · Next-day fitting · 10-year warranty
Your local picture
- Region
- Greater London
- Typical housing
- 1960s-80s
- Fitting time
- 1 day (combi)
- Warranty
- Up to 10 yrs
2026 price guide
- Budget A-rated combi
- £1,800 – £2,400
- Mid-range (Worcester/Vaillant)
- £2,500 – £3,500
- Premium / system boiler
- £3,500 – £5,000
- Payback vs old G-rated
- 2 – 4 years
Upgrading your Harrow boiler in 2026.
An A-rated condensing boiler runs at 90%+ efficiency, compared to 60–70% for a typical G-rated unit that's 15+ years old. For an average Harrow semi on gas, that's around £300–£500 a year off the heating bill — enough to pay back a new install in 2–4 years.
Most Harrow homes with 1960s-80s-era housing stock are a straightforward combi swap — fitting completes in a single day and you've got hot water again the same evening. System and regular (heat-only) boilers take longer but suit larger homes with multiple bathrooms.
All our partners are Gas-Safe registered — the UK legal requirement for any gas work — and most offer 10-year parts and labour warranties on premium Worcester Bosch, Vaillant and Viessmann installations.
Flexible options in Harrow.
0% finance available
Spread the cost over 2–10 years interest-free, subject to status. Typical £25–£60/month.
ECO4 free boiler
Low-income households may qualify for a fully-funded boiler replacement under ECO4.
Next-day fitting
Most quotes include next-day or same-week fitting in emergencies — you won't be left without heating.
10-year warranty
Premium Worcester Bosch, Vaillant and Viessmann boilers come with up to 10-year parts and labour cover.
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