How Much Does a New Boiler Cost?

  • Written by David
  • Last updated 10 February 2025

Boiler Replacement Facts

  • Replacement Costs: Replacing a boiler in 2025 will cost between £2,000 and £4,500, depending on the type and complexity of the installation.
  • Combi Boiler Replacement: Opting for a like-for-like combi boiler replacement is among the more affordable options, with an average price submitted to WhatPrice of £2,802.
  • Simple Like-for-Like Replacement: If you’re replacing an old boiler with a similar new model (e.g., combi to combi), the installation can often be completed in one day.
  • Avoid Peak Seasons: Install a boiler during off-peak times, such as summer, when demand for engineers is lower, often leading to reduced prices.

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New combi boiler installation

Installing a new boiler can be a relatively straightforward and hassle free experience, provided you do your research first.

It can be very tempting when you’re without heating or hot water to rush into accepting the first quote you receive, without carrying out a few checks into the company beforehand.

We’ll look at all the options to ensure you get the best price from a reputable heating engineer quickly, often the very next day – but first we’ll look at how much a typical boiler replacement will cost.

Average costs by boiler type

Combi boiler

As it requires the least components, a combi boiler is the cheapest. It is a compact, all-in-one unit that produces hot water on demand. Combi boilers are best suited to smaller homes with up to 3 bedrooms and one bathroom. The combi boiler takes its water supply directly from the mains.

System boiler

A system boiler is a better option for larger homes with a greater demand for hot water and more radiators but will cost more to install. In addition to the boiler itself, you will also need a hot water cylinder which will store additional hot water to meet the higher demand.  Like a combi boiler, the system boiler takes its water supply from the mains.

Conventional / Regular boiler

A traditional regular boiler will be comparable to a system boiler in terms of price. These systems also require a hot water cylinder but take their water supply from a feed tank which is usually stored in the property’s attic.

Boiler typeApproximate price range
Combi£600 – £3,000
System£800 – £3,500
Conventional/Regular/Heat-Only£800 – £3,500

Installed prices

Boiler typeInstalled Cost RangeWhatPrice Average*
Combi£2,000 – £3,000£2,802
System£2,500 – £4,500£2,967
Conventional £2,500 – £4,000£2,878
* Average of actual prices submitted to WhatPrice by homeowners who have had a boiler installed

Average costs by fuel type

The type of fuel that a boiler uses to produce heat will also influence the price you pay.

New gas boiler

Gas boilers tend to be the cheapest to run once they are installed and although cheaper to install than an oil boiler, they are more expensive than an electric boiler.

New oil boiler

An oil boiler will be more costly to install than electric and gas boilers, and the fuel needs to be delivered regularly and stored on your property in an underground container.

New electric boiler

An electric boiler is often the simplest and quickest type of boiler to install which results in lower installation costs. However, electricity can be an expensive way to power a heating system, unless you are generating your own free electricity via solar panels.

Boiler fuel typeApproximate price range
Gas£2,000 – £3,500
Oil£2,500 – £5,000
Electric£1,500 – £3,000

Additional costs of a new boiler

Labour costs will add to the cost of buying the boiler itself. These costs can range from approximately £500 for a straightforward, like-for-like boiler installation, all the way up to £3,000 for more complex and time-consuming the work.

Other elements that can make the job more complicated are the location of the boiler, how many engineers are needed to carry out the work, and the type of heating system being installed.

There are instances when additional equipment or accessories are needed to ensure the new boiler will work as effectively and efficiently as possible. This might include a magnetic filter to remove metallic debris that can clog the system over time, a smart thermostat, or a chemical flush to clean the system of old dirt and debris before connecting the new boiler.

If you need to replace radiators, flue, condensate pipe, or other general pipework as part of the installation, this will also add to the cost of a new boiler and possibly make the installation more complicated.

Worcester Bosch 8000 regular boiler

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Factors affecting boiler cost

Boiler brands

One of the biggest factors influencing the cost of a new boiler is the brand that you choose. There are several boiler brands out there, but the leading brands in the UK are listed below.

Alpha

Alpha has been manufacturing and installing heating systems for more than 55 years. Today they offer a range of Combi, System, and Regular (Heat-Only) boilers, air source heat pumps, and hybrid heat pumps for both domestic and commercial settings.

Baxi

Baxi is a brand owned by a parent company, BDR Thermea. They have been manufacturing in the UK since 1866 from their site in Preston. The product range includes boilers, air source heat pumps, combined heat and power (CHP) units.

Glow-worm

With a history dating back to 1934, Glow-worm has been producing heating solutions from its foundry in Derbyshire for more than 90 years. While the brand is proudly British, since 2001 it has been owned by The Vaillant Group which is Europe’s second-largest heating company.

Ideal

Ideal Heating has been producing central heating solutions for homes and businesses since 1906. The Ideal product range includes gas boilers, heat pumps and heating controls.

Vaillant

Founded by Johann Vaillant 150 years ago, the Vaillant brand strives for a ‘greener and more sustainable lifestyle’ for their customers, specialising in energy-efficient and low-carbon heating solutions. The product range includes gas boilers, heat pumps, hybrid systems, and the company is investigating hydrogen boilers as a potential, green alternative to gas.

Viessmann

Viessmann was founded in 1917 in Allendorf, Germany, as a heating manufacturer, but has evolved to become Viessmann Climate Solutions. The company focuses on sustainability in its products and initiatives which range from energy-efficient boilers to heat pumps and solar-powered systems.    

Worcester Bosch

Arguably one off the best-known boiler brands in the UK, Worcester Bosch began as Worcester (named after where it was based) in 1962. Now part of the Bosch Group, the brand has grown from a small engineering works to one of the market leaders in heating solutions. The product range includes boilers, heat pumps, and hybrid systems.

This table illustrates the approximate price of a boiler from each brand, excluding installation costs. It is important to note that these figures are estimates based on market research and will vary depending on the type of boiler you are installing and the supplier you choose.

BrandApproximate price
Alpha£650 – £1,200
Glow-worm£650 – £1,200
Ideal£700 – £1,500
Baxi£700 – £1,400
Worcester Bosch£800 – £1,800
Viessmann£1,200 – £1,800
Vaillant£1,200 – £1,900

Boiler size

Boiler size is measured in kWh and typically ranges between 24 and 42kWh. The more powerful your boiler needs to be, the more expensive it will be. But how do you work out how powerful your boiler needs to be?

The more bedrooms, radiators and bathrooms that you have, the more powerful the boiler needs to be so that it can provide enough hot water for all your needs. A boiler that is too small is likely to underperform and will be put under a lot of strain, leading to more frequent breakdowns and shortening its lifespan.

On the other hand, a boiler that is too powerful will be using more energy than necessary, increasing your heating costs.

House size

While it is important that a qualified heating engineer visits your home to recommend the right size of boiler for your heating and hot water needs, the table below gives a rough guideline.

Property sizeBoiler sizeApproximate price range
2-bedroom house / flat18kW – 27kW£600 – £1,800
3-bedroom house  24kW – 34kW£700 – £2,900
4+-bedroom house35kW – 43kW£800 – £3,500

How much could you save with an energy efficient boiler?

Replacing your old boiler with a newer more efficient model can help reduce your energy bills. Estimated annual savings are as follows.

Initial installation costs may seem significant, but the long-term energy savings often justify the investment in a modern efficient boiler.

Type of propertyYour old boiler efficiency rating & potential saving
DEFG
(78-82%)(74-78%)(70-74%)(<70%)
Bungalow (detached)£160£180£210£290
Detached house£220£270£340£490
Flat (mid floor)£65£75£85£120
Semi-detached house£180£200£220£320
Mid-terrace house£150£170£190£270
These are estimated figures provided by the Energy Saving Trust based on installing a new A-rated condensing boiler with a programmer, room thermostat and thermostatic radiator controls (TRVs) in a gas heated home from an older boiler with a programmer and room thermostat. Savings will vary depending on the size and thermal performance of your home. Figures are based on fuel prices as of November 2024. 

How to save on new boiler costs

Get multiple quotes

It’s important to get multiple quotes for boiler replacement as there can be significant variation between companies. Online installers can be a good starting place to get a quick idea of price and fast installation but be aware they will generally use sub-contractors.

Comparison websites are a good tool to help you find the best price and quickest access to a few installers but be mindful they may not be as local as they suggest. Multinational companies should be included in your search for the sake of comparison, but they’ll probably be more expensive than a local installer.

Try and find an accredited installer for reassurance of a good level of vetting from the manufacturer, product knowledge and longest warranty.

Choose the right boiler

Try to go for a like-for-like boiler swap as this will minimise the amount of labour required and the level of disruption to your home while the work is carried out. Of course, this might not always be possible due to boiler model/regulation changes (for example, if you are getting rid of a back boiler you will not be able to do a like-for-like replacement) but if you can, it’ll be the easiest and quickest install you can find.

Online installers are great for straightforward boiler replacements, especially combi to combi. Anything more complicated such as a full central heating system installation then it’s best to get a local installer to assess your requirements.

Time your purchase

During the colder months heating engineers are typically much busier and therefore charge more for their time. Scheduling your boiler replacement at the end of Spring or in early Summer will be a quieter time for heating engineers and when you’re most likely to get the best price. It will also cause the least disruption as you won’t mind if the heating is off!

Finance options

It is possible to spread the cost of a boiler replacement over a fixed period of time to avoid having to pay the entire cost upfront. However, it’s important to consider any interest or other fees that you will be paying as this will increase the overall cost, and you need to be confident you will be able to make the repayments for the whole period. Applying for finance can impact your credit score, and missing payments could damage your credit score.

Government boiler grants

There are government grants and other support schemes available to help those who meet the eligibility criteria to improve the efficiency of their home heating, including the Boiler Upgrade Scheme and the Energy Company Obligation (ECO). 

Government grants and schemes for boilers

Boiler Upgrade Scheme

The Boiler Upgrade Scheme provides eligible applicants with a grant to cover part of the cost of replacing an oil, gas, electric, or LPG boiler with a biomass boiler or a heat pump. The scheme is open to people in England and Wales and offers £7,500 towards the cost of installing an air source heat pump or ground source heat pumps, and £5,000 towards the cost of a biomass boiler.

The new heating system needs to meet certain efficiency levels. To apply for the scheme, you need to own the property you are installing the heating system into and be replacing a fossil fuel heating system. More detail about eligibility criteria is available on the government website.

The Energy Company Obligation (ECO) scheme

The ECO scheme was introduced by the government to address fuel poverty in the UK and reduce carbon emissions. There have been several versions of the scheme (ECO, ECO1, ECO2, and ECO3). ECO3 closed on 31st March 2022 with ECO4 covering installations between 1st April 2022 until 31st March 2026.

Under the ECO scheme, medium and large energy suppliers have agreed to promote measures that help fuel-poor, low income and vulnerable households to heat their homes. This might include improving their heating system or insulation levels.

Looking for a new boiler?

Get free quotes and compare prices with our simple enquiry form today

Boiler financing options

When considering boiler financing options, be sure to pay close attention to the detail before committing. Specifically, how much interest will you be paying, and over what period of time are you committing to make the repayments. Some companies offer interest free finance while others will refer to it as a monthly payment plan.

Overall, you may end up paying more than you would have if you settled the bill upfront, but financing options can provide flexibility and convenience.

Choosing a reliable installer

Life handover

Finding a qualified and reputable heating engineer to assess your property’s heating needs needn’t be too difficult, you just need to understand how the different types of online and offline companies and quotation services work to get the best out of them in the shortest time.

Online boiler replacement companies

Online installers such as Heatable, iHeat & BOXT have become very popular in recent years and for good reason, they offer a fast and efficient way of pricing and arranging a boiler replacement all through their website.

By asking a few very relevant questions about your property and lifestyle they can provide an accurate price online, you can then pick and book an installation date (often as soon as next day) without the hassle of waiting for an engineer to arrive, asses the existing installation and quote – which all takes time.

The downsides of this is exactly that, you never meet anyone from the company before the installation happens. You may be fine with that but sometimes it’s good to meet the installer face-to-face to build a rapport and ensure you’re comfortable with who will be coming into your property before proceeding.

Online companies also generally use subcontractors who are paid a fixed rate to install your boiler, these may be local to you but generally more often than not they won’t be.

The contractors will have been thoroughly vetted beforehand but it’s always best to check they’re Gas Safe Registered beforehand, If it’s an oil boiler then check the Oftec register.

If you’re going to use an online installer for your new boiler then check out their Trustpilot reviews, and read not only the positive reviews but also the negative ones to get a balanced feel for how they’re performing.

We’ve summarised their current ratings across Trustpilot and Google below.

InstallerTrustpilot ratingGoogle rating
Boxt4.8/54.0/5
Heatable4.8/54.4/5
iHeat4.8/54.9/5
Updated February 2025

Found this site useful? Please let others know on TrustPilot

Boiler price comparison websites

Websites such as Checkatrade, Rated People, Trustatrader & MyBuilder list tradespeople that are subscribed to their service, they all provide some degree of vetting before partnering with them and allow users to provide reviews about their experience using the company. This can be a very useful way of quickly finding boiler installers local to you whilst also reviewing their feedback.

You can call the tradespeople directly but one of the best ways to contact the listed companies is to enter your details on the website, they’ll generally offer a free quotation service which can be handy if you’re busy.

You enter your details which will be reviewed and forwarded to 3 or 4 companies that are looking for work and are willing to pay a small fee for your details, this way the installer will know they’re up against a few other companies for the job and will generally be fast to call you and keenly priced, they’ve paid for the privilege after all.

A couple of things to consider when using these services is that they may be local, regional or even national companies that respond to your job so take this into account when talking to them and the ongoing support they provide, and of course use the advice above about checking their Gas Safe or Oftec qualifications.

Using a service like this won’t cost you a penny, and won’t affect the price you pay as the fee the installers pay is small in comparison to the replacement cost. Only enter your details into one website though, or you’ll be inundated with calls.

Accredited local boiler installers

New gas boiler installation

Professional installation is crucial for safety and compliance with Gas Safe and Building Control regulations and one way to ensure you’re getting the best is to go through the boiler manufacturer’s website and find their accredited installers.

The four biggest manufacturers Worcester, Baxi, Ideal & Vaillant all offer this service via their website which will not only provide details of accredited installers near you but will often also provide you with a longer warranty than if you’d had one of those manufacturer’s boilers installed without using an accredited installer.

It also ensures the engineer is fully trained on the specific boiler in hand and that it’s also integrated with the latest heating controls, ensuring optimal performance and energy efficiency. Once installed, thorough testing and commissioning take place to guarantee the system’s functionality in accordance with the manufacturer’s warranty terms.

Using an accredited installer provides you with a good amount of leverage should the installation not go to plan for whatever reason, the accreditation is a valuable source of work for a lot of companies and will be keen to rectify any issues so as not to jeopardise it.

National energy companies

There’s only one truly nationwide energy company that still offers boiler replacements and that’s British Gas, many of the others now either refer you to one of the online companies or only install heat pumps.

Generally installation timeframes can be longer using British Gas and you’re likely to pay more than you would by using a local installer. On the upside you have the reassurance your installation is backed by a large company with well trained engineers, and the support and service to go alongside that.

One thing to note is that if you’re a British Gas HomeCare customer you don’t have to use British Gas for your boiler installation, you’re free to use whoever you choose.

If you have the time it’s always best to arrange a few quotes, try and find a couple of local businesses and then a regional or national installer to compare against.

Tips for the best boiler deal

  • Use online installers to get a quick idea of price and fast installation, but be aware they generally use sub-contractors.
  • Online installers are great for straightforward boiler replacements, especially combi to combi. Anything more complicated such as a full central heating system installation then it’s best to get a local installer to assess your requirements.
  • Use comparison websites to get the best price and quickest access to a few installers, but be mindful they may not be as local as they suggest.
  • Try and find an accredited installer for reassurance of a good level of vetting from the manufacturer, product knowledge and longest warranty.
  • Use multinational companies for a quote comparison compared to local installers, but they’ll probably be more expensive.
  • End of Spring / early Summer is the quietest time for heating engineers and when you’re most likely to get the best price and least disruption as you won’t mind if the heating is off!
  • Try to go for a like-for-like boiler swap, it might not always be possible due to boiler model/regulation changes but if you can it’ll be the easiest and quickest install you can find.

Found this site useful? Please let others know on TrustPilot

User submitted boiler replacement prices

Below you’ll find prices submitted from other WhatPrice users for boiler replacement costs either installed or been quoted, to give you an idea of how much you can expect to pay for a new boiler.

  • The average cost submitted to us by WhatPrice users for a gas boiler replacement is £2,833
Job typeDescriptionPriceUnitsRegionUpdated

Gas Boiler Installation

gas combi

£1,895

Total priceNorth East2025

Gas Boiler Installation

old boiler had failed, needed new one urgently. Had a new baxi combi and new flue fitted for £2450 inc. vat

£2,350

Total priceCymru Wales2025

Gas Boiler Installation

Heating

£2,400

Total priceYorkshire & the Humber2025

Gas Boiler Installation

new boiler

£1,100

Total priceYorkshire & the Humber2025

Gas Boiler Installation

Replacement of old Baxi boiler 45 yrs old, it developed a hole in its casing, brilliant boiler. New Worcester R15i installed £1000, not high spec (for 8 radiators) regular boiler went for like for like to avoid addition plumbing works by British (Scottish) gas. Works ordered and done a week later, lucky I guess at coldest time of year. Magnaclean through whole system carried out but did not resolve issue with any lukewarm radiators. Few ancillary replacements installed as issues getting heating to work (one whole day) but it did recover. One radiator value broken on the day not replaced. Follow up engineer explained that radiators don’t heat up at the bottom 25% as much as they do at the top and will always remain so ???

£3,500

Total priceScotland2024

Gas Boiler Installation

Boiler and flu
Limescale fighter
Full installation
Changing from an old system boiler to combi

£3,800

Total priceLondon2024

Gas Boiler Installation

replaced my old gas boiler for a new a rated vaillant condensing gas boiler, the process was painless and the price ok, they renewed all my radiator valves plus all new controls

£2,735

Total priceWest Midlands2024

Gas Boiler Installation

Worcester Combi Boiler Supply & Installation

£3,160

Total priceScotland2024

Gas Boiler Installation

Move location of boiler from utility to bathroom airing cupboard, new gas and cold water feeds to boiler. Install new Worcester Bosch Combi 28Cdi plus flue/drain. Remove existing boiler,tank/scrap and pipes. New wiring for programmed Drayton thermostat and TRV’s. New cold stop tap and 3 new cold/hot feeds to bathroom and kitchen basins. Left scrap to value £200

£3,425

Total priceWest Midlands2024

Gas Boiler Installation

New Vaillant Combi, wireless controls, magnaclean, powerflushing of the heating system, 7 year warranty included.

£2,898

Total priceSouth West2024

Gas Boiler Installation

Remove the existing boiler replaced with A rated boiler condensing combi boiler New boiler would be fitted on where the existing is. power flush the radiators finally the boiler commissioning and notification with Gas Safe labour cost materials & boiler all included on the quote. Potterton titanium boiler.

£2,240

Total priceLondon2024

Gas Boiler Installation

Worcester Bosch 28cdi Greenstar. Magnaclean, full system flush, TRV’s on radiators, Inhibitor, Danfoss wireless controls.

£3,295

Total priceNorth East2024

Gas Boiler Installation

New boiler, flush system, fit a magnaclean and supply 10 year warranty, house heats up in ten minutes, hot water is there in five seconds, we put up with the last combi 9 years.

£2,800

Total priceWest Midlands2024

Gas Boiler Installation

Replace systems boiler with high efficiency combi boiler Vokera with RF stat & programmer

£1,730

Total priceScotland2024

Gas Boiler Installation

vaillant boiler, with a new fernox filter and wireless room thermostat

£2,475

Total priceNorth West2024

Gas Boiler Installation

Replace standard boiler with new 18kw Worcester bosch condenser boiler, moving location slightly from one wall of corner to the other. Plus 4x thermostatic Radiator valves. Also installed outdoor tap.

£2,500

Total priceEast Midlands2024

Gas Boiler Installation

Combi boiler removed and another installed in its place. The engineer recommended a Vaillant Eco Tec Plus. We got 7 years warranty as well. 7 radiators powerflushed which took a whole day.

£2,400

Total priceSouth East2024

Gas Boiler Installation

Replace back boiler with new condensing boiler in different position

£4,350

Total priceNorth West2024

Gas Boiler Installation

Boiler replacement, new flue and run a condense pipe, change radiator valve add inhibitor refill system.

£2,633

Total priceSouth East2024

Gas Boiler Installation

replace combi boiler with the same in a newer version

£1,800

Total priceLondon2024

Gas Boiler Installation

Took out old back boiler and replaced it with a Vaillant 28 combi boiler. flushed system and installed a filter

£4,250

Total priceNorth East2024

Gas Boiler Installation

We had a new combination boiler fitted , the previous one had a leaking heat exchanger which also mucked up the electric control board , we had a new Heatline 24kw A rated boiler fitted with a replaced wall thermostat, system was cleaned out with a chemical & some type of magnetic gadget, chemicals were than put in,

£1,800

Total priceSouth East2024

Gas Boiler Installation

supply and fit Worcester 37cdi combi boiler 6 radiators bungalow 5 rooms

£4,230

Total priceNorth West2024

Gas Boiler Installation

had a boiler upgraded, engineer was helpful and gave a lot of info and requirements, highly recommended old unvented cylinder and floor standing boiler removed upgraded with condensing boiler.

£2,700

Total priceNorth West2024

Gas Boiler Installation

Fitted an old combi boiler for a new vaillant one.

£2,050

Total priceLondon2024

Gas Boiler Installation

Replace existing combi boiler with Worcester boiler, fit thermostats to nine rads and fit one new rad.

£4,000

Total priceSouth East2024

Gas Boiler Installation

Replace gas boiler and 19 thermostatic radiator controls and add one new radiator

£3,975

Total priceSouth East2024

Looking for a new boiler?

Get free quotes and compare prices with our simple enquiry form today

Boiler fit only prices

New boiler installation

You can buy a boiler from a supplier and then find a heating engineer to fit it for you, this can save you money but be aware if anything goes wrong with the boiler then it can be harder to arrange support from the original installer, not always but it is something to consider. We would advise you find an installer before purchasing the boiler as they generally prefer to supply the boiler themselves. Once you find a willing engineer ensure they are Gas Safe Registered and that they’ll notify Gas Safe of the installation, when this happens Gas Safe will notify your local building control who will issue a Building Regulations Compliance Certificate.

These are example prices from WhatPrice users for heating engineer labour charges to fit a boiler for you. The actual cost will vary with ease of integration into the existing system and the type of fuel required. E.g. a simple replacement of an old combi boiler for a new one with little modification will cost less than if your property has never had a boiler in that location.

  • The average cost submitted to us by WhatPrice users for fit only of a gas boiler is £812
Job typeDescriptionPriceUnitsRegionUpdated

Gas Boiler Installation

Changing old convectional boiler to combi. Relocation was into the new loft. ran a new 28mm gas line, powerflush and magnaclean installation, labour only

£1,850

Labour onlyLondon2024

Gas Boiler Installation

Old and broken one replaced with new combi boiler. I thought I paid a lot but actually what i paid seems cheap! Very professional, polite and tidy engineer.

£535

Labour onlyEast of England2024

Gas Boiler Installation

Combi swap with all relevant certificates

£735

Labour onlyEast Midlands2024

Gas Boiler Installation

remove old cylinder and tank. install a new combi boiler in the kitchen with wireless thermostat. I provided the boiler. I think is on the high side but I paid as he will do it the next day (took 2 days)

£922

Labour onlyLondon2024

Gas Boiler Installation

Change old british gas boiler for new (supplied by myself and change 3 radiators (one new supplied by myself).

£822

Labour onlyEast Midlands2024

Gas Boiler Installation

Like for like combi boiler replacement in same location (supplied by me) Supply and fit magnaclean filter.

£1,100

Labour onlyLondon2024

Gas Boiler Installation

I had a conventional boiler replaced with the same conventional boiler but bigger 30KW

£1,300

Labour onlyLondon2024

Gas Boiler Installation

Change from gravity fed to combi-system. remove 3 header tanks and all plumbing in loft. new boiler in same location as old. price includes labour, waste disposal and copper. provide cold feed and waste for washing machine.

£1,000

Labour onlyWest Midlands2024

Gas Boiler Installation

REMOVING AND FITTING A NEW MAIN COMBI BOILER

£915

Labour onlyNorth West2024

Gas Boiler Installation

Replaced old combi boiler with new condensing combi boiler in same location in kitchen (easy access). Included new flue kit of course, but core supply of gas, water and electricity were already there as it was a replacement.

£490

Labour onlyLondon2024

Gas Boiler Installation

Remove old combi boiler and replace with condensing vaillant combi.

£600

Labour onlyNorth West2024

Gas Boiler Installation

change vaillant combi to combi, and run 22m gas pipe from meter, power flush system

£560

Labour onlyLondon2024

Gas Boiler Installation

Take out old combi boiler. Fit new combi boiler. drain down system and test. 4 Bed house, 12 Radiators. All done within 6 hours.

£450

Labour onlyEast Midlands2024

Gas Boiler Installation

the price is for replacing an existing combination boiler with a landlords safety certificate.

£590

Labour onlyLondon2024

Gas Boiler Installation

Replace old heat only boiler with new Vaillant Eco tech heat only boiler. Flue and associated pipe work

£515

Labour onlyLondon2024

Gas Boiler Installation

Remove old non condensing combi and ft Glow Worm condensing combi. Condensate drain added, system flushed and protector added. All work carried out and notified by Gas Safe Engineer.

£600

Labour onlyLondon2024

Warranty, Service & Maintenance

Buying a new boiler is a significant investment, but it should continue to provide your home with heating and hot water for several years to come. Of course, things can and do go wrong from time to time, which is why boiler manufacturers will usually include a warranty period.  

Standard warranty periods tend to range from 2 to 10 years depending on the brand and model of boiler that you choose. Obviously, the longer the warranty, the greater your peace of mind. Some manufacturers will give you the option to extend the warranty for an additional fee. 

Whatever the length of your boiler warranty, however, it’s important to note that in most cases you will need to have the boiler serviced annually by a qualified engineer. If the boiler is not serviced regularly, the warranty may no longer be valid.  

Aside from keeping your warranty intact, annual servicing is a good idea in general as it will keep your boiler running efficiently (which means keeping energy bills to a minimum) and prevent expensive breakdowns. Some manufacturers offer annual servicing packages either as part of a promotional offer, or you may be able to pay on a monthly basis to avoid having to part with the annual servicing fee all in one go.  

Looking for a new boiler?

Get free quotes and compare prices with our simple enquiry form today

FAQs

A combi boiler swap is the cheapest and fastest boiler to install, according to our figures you can expect to pay around £2,802 for a combi replacement.

Yes, many suppliers offer financing options such as 0% interest-free credit, pay monthly plans, or buy now, pay later schemes. Check with your installer for available offers.

A straightforward boiler swap can generally be done in 1-2 days, if any other system changes are required such as new pipework, radiators or a new tank then anything from 2-5 days is reasonable.

Most new boilers come with a warranty of 5 to 12 years, covering parts and labour. The longest warranties are generally found by using an engineer accredited by the manufacturer. Ensure your boiler is serviced annually to keep the warranty valid.

A conventional boiler heats water that is stored in a hot water cylinder. The tank is often placed in an airing cupboard usually off the landing. There is also a cold water storage and an expansion cistern in the loft. The advantage of this is that a large volume of water (at a reasonable pressure head) is available, the disadvantage is that the hot water is not available on demand. Heating up the large volume of water in the tank has a cost disadvantage if only a small amount is needed (a combi boiler is better in this case), but the systems are relatively cheap to maintain and good for larger homes that have high hot water demand. Many older systems that are in need of replacing are conventional boilers.

A combi boiler differs in that the water is not stored in a tank anywhere (cold or hot), but rather supplied on demand when you need it. The term combination comes from the fact that it provides hot water for washing and hot water for heating.

The advantages are that they save space (no pipework or tanks in the loft) and hence are easier to install (for a professional). Also, by heating only the water you want you can save money and be more environmentally friendly. The disadvantage is that the flow rate from the boiler can be slower depending on mains pressure and boiler size. A more powerful combi boiler could provide hot water at mains pressure and also sustain a decent flow rate through more than one tap at a time again depending on mains pressure.

It used to be the case that combi boilers were better suited to smaller houses (where the likelihood of more than one tap being used was reduced). However, there are new types of combi that have a small storage tank that means that can cope with a higher flow rate.

A condensing boiler uses advanced technology to maximize the efficiency of the heat it produces. When burning fuels like gas or oil, gases are released through a flue. In a traditional non-condensing boiler, these gases are released into the air, and their heat potential is wasted.

In contrast, a condensing boiler captures and reuses the hot gases by directing them through a heat exchanger into what’s called the primary circuit. Depending on the type of boiler, this primary circuit then distributes the heat to either the heating system (radiators) or the hot water supply. In a combination boiler, the hot water is usually heated through a secondary heat exchanger known as a plate-to-plate system. In a heat-only setup, the domestic hot water is heated and stored in a cylinder within the property.

The required heat output of your boiler is determined by the total requirement of all your radiators and your hot water needs. Allowance needs to taken for the heat loss through the walls, floor, windows and roof of your house. Therefore, if a property has undergone a serious insulation makeover (cavity walls, double glazing, draft reduction, loft insulation) you may find your need a smaller boiler capacity. The specific calculation/estimation will be done by your plumber.

Depending on the type of boiler you are replacing, yes, it is possible to save money by upgrading. If your boiler is more than 10 years old, is non-condensing, and/or is not A-rated for efficiency, you could make savings on your energy bills by switching to a brand-new model. You could maximise these savings by also improving your home insulation and, if you have one, your hot water cylinder.

A smart thermostat is connected to the internet which means you can remotely control your home’s temperature via a tablet, smartphone or desktop computer. They give more detailed insights into your energy usage and give greater control over your central heating usage. For example, using an app on your phone, you could turn your heating up, down, on or off, from anywhere in the world.

Whether you should install a smart thermostat or not depends on your lifestyle and how you choose to use it. The enhanced controls and insights can give you the tools to minimise your energy usage and identify when/where you are using the most energy.

Simple boiler installations, e.g., replacing a combi boiler with a new combi boiler in the same location could be completed in as little as four hours. However, installing a new type of boiler is likely to take longer, and if it is being installed in a new location this will again add time to the job. For particularly complex installations, the work may take 4-5 days to complete.

In most cases it is not necessary to replace radiators when installing a new boiler. However, if your radiators are particularly old, damaged (rusty, leaky) or inefficient, or you are switching to a new heating system, you may want to consider upgrading, as newer radiators may be more energy efficient.  

Generally you can choose to have a boiler installed in any room in your home, but there are B Building Regulations to consider for safety and environmental reasons. A qualified installer will be able to explain your options. 

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