Vaillant
ecoFIT pure 425
25kW conventional · 10-year manufacturer warranty
£2,779
Fixed price, fully installed (like-for-like)
Conventional boiler pricesConventional boiler prices,
Conventional boiler prices,
fully installed.
Fixed prices for a like-for-like conventional boiler replacement – also called a regular or heat-only boiler – in homes with a hot water cylinder and tanks in the loft.
About conventional (regular) boilers
A conventional boiler works with a hot water cylinder and a cold water tank in the loft, plus a small feed and expansion tank. It is common in older houses.
Keeping the same type of system is usually the simplest replacement. If you are thinking of switching to a combi or system boiler instead, the extra work is priced at your free survey.
Every price includes
- New boiler and flue kit
- All materials and installation
- Magnetic system filter
- Chemical system flush
- Commissioning and Building Regulations notification
- Removal and disposal of your old boiler
Prices from £2,779. Checked 2026-10-31.
24–26kW conventional boilers
Homes with up to about 12 radiators.
Vaillant
ecoTEC plus 424
24kW conventional · 10-year manufacturer warranty
£2,840
Fixed price, fully installed (like-for-like)
30–32kW conventional boilers
Homes with about 13–15 radiators.
Vaillant
ecoFIT pure 430
30kW conventional · 10-year manufacturer warranty
£2,869
Fixed price, fully installed (like-for-like)
Vaillant
ecoTEC plus 430
30kW conventional · 10-year manufacturer warranty
£2,925
Fixed price, fully installed (like-for-like)
Worcester Bosch
Greenstar 8000+ 30 Regular
30kW conventional · 12-year manufacturer warranty
£3,165
Fixed price, fully installed (like-for-like)
35–36kW conventional boilers
Homes with about 16–19 radiators.
Worcester Bosch
Greenstar 8000+ 35 Regular
35kW conventional · 12-year manufacturer warranty
£3,499
Fixed price, fully installed (like-for-like)
Vaillant
ecoTEC plus 435
35kW conventional · 10-year manufacturer warranty
£3,599
Fixed price, fully installed (like-for-like)
Vaillant
ecoFIT pure 435
35kW conventional · 10-year manufacturer warranty
£3,599
Fixed price, fully installed (like-for-like)
40kW conventional boilers
Larger homes with 20 or more radiators.
Worcester Bosch
Greenstar 8000+ 40 Regular
40kW conventional · 12-year manufacturer warranty
£3,839
Fixed price, fully installed (like-for-like)
45kW conventional boilers
Very large homes – confirmed at survey.
Worcester Bosch
Greenstar 8000+ 45 Regular
45kW conventional · 12-year manufacturer warranty
£4,169
Fixed price, fully installed (like-for-like)
50kW conventional boilers
Very large homes – confirmed at survey.
Worcester Bosch
Greenstar 8000+ 50 Regular
50kW conventional · 12-year manufacturer warranty
£4,509
Fixed price, fully installed (like-for-like)
Priced at your free survey
The prices above are for a like-for-like replacement. If your home needs extra work, it is priced at your free survey before you agree to anything, for example:
- Moving the boiler to a new position
- Replacing a floor-standing or back boiler
- Changing system type (for example to a combi)
- A vertical flue through the roof, or a plume kit
- A new condensate drain pipe for an older boiler
- Upgrading the gas supply pipe (often to 22mm)
Which size do I need?
The right size depends on your bathrooms, radiators and hot water use – not just the size of the house. Our online boiler price asks a few quick questions and recommends the right boiler, and the free survey confirms it.
Who fits your boiler
Your boiler is fitted by one of our approved, Gas Safe registered installation partners. Your written quotation names the installer, who your contract is with, and your warranty and workmanship guarantee. Manufacturer warranties need the boiler registered and serviced every year.