New Boiler Costs at a Glance
Prices below are for supply and full installation in Kent, including all pipework connections, flue, commissioning and warranty registration. Updated June 2026.
| Job Type | Cost From |
|---|---|
| Like-for-like combi replacement | From £2,200 |
| System boiler replacement | From £2,400 |
| System-to-combi conversion | From £2,900 |
| Back boiler removal & combi install | From £3,500 |
| New combi (no existing boiler) | From £3,000 |
| Unvented cylinder installation | From £1,500 |
All prices are subject to survey and may vary depending on property and pipework.
💡 Why the range? The main variables are boiler model (entry-level vs premium), the complexity of the pipework, flue routing, and whether any additional work is needed such as a magnetic filter, scale reducer or system flush. We give fixed-price quotes after a free survey so you know exactly what you'll pay.
What's Included in the Price?
When HeatCool quotes for a new boiler, the price always includes:
- ✓ Supply of the new boiler
- ✓ Full installation including all pipework connections
- ✓ New flue (or reuse of existing flue where suitable)
- ✓ Gas and water connections
- ✓ System inhibitor dose
- ✓ Full commissioning and pressure test
- ✓ Manufacturer warranty registration on your behalf
- ✓ Building Regulations notification (where required)
- ✓ Removal and disposal of the old boiler
Boiler Brands We Install
We install all major brands. Here's how they compare on price and what we recommend for different budgets.
Vaillant
From £2,400 fitted
Our most-installed brand. Excellent reliability, long parts availability and strong warranty. Our top recommendation for most Kent homes.
Worcester Bosch
From £2,200 fitted
Premium build quality and excellent customer support. A strong choice for larger homes and those wanting maximum reliability.
Glow-worm
From £2,000 fitted
Great value without compromising on quality. Made by the same group as Vaillant. Good choice for budget-conscious homeowners.
Ideal
From £2,000 fitted
British-made boilers with competitive pricing. A reliable mid-range option with good parts availability across Kent.
What Affects the Final Cost?
Several factors can push the price up or down from the ranges above:
Boiler location change
Moving a boiler to a new location means new pipework runs, which adds cost. Staying in the same location keeps costs down.
Flue routing
A standard horizontal flue through an external wall is included. Longer flue runs, vertical flues or awkward routing adds cost.
System condition
If the existing system has significant sludge build-up, a power flush before the new boiler is installed may be recommended to protect it.
Additional accessories
Magnetic filter (£80–£120), scale reducer (£60–£100) and smart thermostats (£100–£250) are optional but worthwhile additions.
Frequently Asked Questions
How long does a new boiler installation take?
A straightforward like-for-like combi replacement takes one day. A system-to-combi conversion or back boiler removal typically takes one to two days depending on the pipework involved. We'll give you a clear timeframe in your written quote.
Is a new boiler worth it?
In most cases yes — particularly if your current boiler is over 12 years old. Modern A-rated boilers run at over 90% efficiency versus 70–75% for older models, which can reduce your annual gas bill by 15–30%. Add in the reduced repair callouts and the peace of mind from a manufacturer warranty, and the payback period is typically 4–6 years.
Do I need a combi boiler or a system boiler?
For most homes with one or two bathrooms, a combi is the right choice — no cylinder, instant hot water, compact installation. For larger homes with three or more bathrooms and high simultaneous hot water demand, a system boiler with an unvented cylinder usually performs better. We'll advise on the right setup during a free survey.
What warranty comes with a new boiler?
Manufacturer warranties vary by brand and model — Vaillant offers up to 10 years, Worcester Bosch up to 8 years, Glow-worm up to 7 years. Warranties are typically conditional on annual servicing. We register the warranty on your behalf on the day of installation.
Can I get finance for a new boiler?
We don't currently offer in-house finance, but many homeowners use a personal loan or 0% credit card for boiler replacements. Some manufacturers also offer finance through approved installers — ask us when you request your quote and we'll let you know what's available.
Do you offer free quotes?
Yes — all our surveys and quotes are free with no obligation. Call 07415 078644 or send us a WhatsApp and we'll arrange a convenient time to visit and give you a fixed-price quote.