Gas boiler replacement and the process of buying a new boiler is something nobody wants to do. But, when you need to, you'll want to get it right. This is the ultimate guide to new boiler replacements.
The boiler is a key part of any modern home, supplying hot water to your outlets and your home’s central heating system.
If you have a broken boiler, you'll start to smell and your house will be cold.
Traditionally, shopping for a new boiler replacement has been complicated, expensive and exhausting. But, we fixed that, by taking the entire process online.
In this boiler replacement installation guide, we summarise the most important factors any savvy boiler buyer should know.
PS We fit new boilers with gas-safe installation nationwide. Simply answer these questions, get your fixed price and you could get it installed as quickly as tomorrow.
Boiler Replacement Key Points:
Boiler installation costs and timelines depend on a variety of factors including the type of boiler e.g. combi or system, as well as whether you want to move your boiler to a new location.
All new boiler quotes with Heatable include new boiler installation, parts, labour and VAT.
You can pay for your new boiler in monthly instalments and with zero interest.
A 12-year boiler warranty is available for certain models.
Next-day boiler installation is available (subject to installer availability).
New boiler prices are fixed, so won't change, get your custom boiler quote here.
New Boiler Costs
This question is perhaps the first one that comes to the mind of anyone thinking about a new gas boiler replacement installation.
For an absolutely massive and excessively long guide, check out our new boiler costs bible.
Gas boiler replacement with Heatable starts from around £1,950 - supplied and fitted*
*Based on simplistic, like-for-like combi boiler replacements in the same location.
However, for illustration purposes here's a quick guide to what some of our starting prices are for different types of combi boiler installations (2024):
New Boiler Replacement Type | ~ £Cost |
Combi Boiler Replacement | £1,950 |
System/Regular Conversion | £2,545 |
Back Boiler Conversion | £2,795 |
To get a more accurate, up-to-date price for your home, head to https://heatable.co.uk/compare/boiler-quotes
The reality is that no new boiler installation is pocket change.
But, for a modern, efficient boiler that is going to be supplying your home with hot water, comfort and Pantene Pro-V cleansed locks for years to come, it’s well worth the investment.
Boiler replacement costs can vary a lot and this depends on a variety of factors, which can be summarised as follows:
The type of boiler you have installed e.g. combi or system
The model you choose e.g. mid-range vs. premium
If you want to move your boiler to a different location
If you want to convert from one boiler type to another
Any extras you purchase e.g. smart thermostats, filters etc
For example, a straightforward combi swap (replacing your current combi with another) is going to be cheaper than converting from a system to a combi boiler.
This is because these installations are more complex, requiring more time, more labour and typically more materials. More everything.
It also depends on the model of boiler you choose, we offer more value-orientated brands such as Alpha, as well as premium, award-winning boiler brands such as Worcester Bosch and Viessmann.
The good news is that we offer multiple ways to pay for your replacement boiler, including cash and new boiler pay monthly deals.
Read our more in-depth complete guide on new boiler costs.
Boiler Replacement - What's included in your new boiler installation?
When you get your new boiler via a Which approved boiler installer like Heatable, you will get all of the following as standard:
The new boiler itself e.g. combi, system or conventional boiler
All required parts including boiler flue and pipework
A complete system cleanse to help prevent corrosion of your new system
Extras including a boiler filter - help to prolong the life of your system
A wireless, programmable room thermostat
A 10-year parts and labour warranty on your new boiler fitting
Why should you replace your boiler with Heatable?
We are a Which? approved boiler installer
All our new boiler replacement quotes are offered at a fixed price - once quoted, they'll never change
Next day boiler installation is available nationwide (subject to availability)
Up to 12 year warranties on some of our boiler installations
All engineers fitting your new gas boiler are registered as Gas Safe
Over 10,000 happy customers – an average score of 4.9 on Trustpilot (that’s better than the market leader).
Price match guarantee – if you find a cheaper new boiler quote, we will match (must be like for like)
Multiple payment options - interest-free boiler finance available
What do Heatable customers have to say?
Feel free to read over 10,000 customer reviews for Heatable on Trustpilot.
In the meantime here are a few videos from some of our happy customers:
Boiler replacement factors to consider
Since a new boiler installation is by no means a cheap process, it’s important to consider some key factors before making your decision. These include:
What size boiler do you need? (kW output)
When considering boiler size, it typically refers to the boiler’s power output and not the dimensions of the boiler.
A boiler's power is measured in kilowatts (kW), so put simply, the greater the kW, the greater the capacity of the boiler to meet your property's hot water and heating requirements.
Typically, boiler manufacturers will offer their boilers in a range of different sizes. Your boiler installer (or, our online process) will determine what size you need from the number of radiators in your house.
For instance, if you live in a small bungalow, then a small combi boiler is probably going to be recommended.
Curious to know which boiler brand performed worst? Find out in our report of the worst boilers.
However, if you live in a large, lavish home with many rooms, then a large-sized boiler will be required to meet the heating demands.
Here are some examples of recommended boiler kW outputs based on your home’s estimated demands:
What size boiler for… | 1 Bath/Shower | 2 Baths/showers | |
2 Bedroom House | 26kW | 29kW | |
3 Bedroom House | 29kW | 35kW | |
4 Bedroom House | 29kW | 35kW | |
5 Bedroom House | 35kW | 35kW |
Location of the new boiler
Where do you want your replacement boiler to be installed? It usually makes financial sense to install it in the same location as your old boiler as it makes the job more straightforward.
However, if you want to move your boiler to a different location, that’s also possible, but you should be prepared to pay more.
Moving your boiler requires more labour and materials e.g. a new flue installed and new pipework re-routing through your home.
It can also make one hell of a mess.
Learn all about combi boilers in our what is a combi boiler guide.
Energy efficiency of new boilers
Securing one of the most energy-efficient boilers will ensure you help reduce your carbon footprint, save money on your heating bills and keep you feeling all warm and fuzzy on the inside.
All the boilers offered by us at Heatable are modern A-rated boilers, which can be purchased with a smart thermostat, such as Nest to ensure you reduce energy wastage even more.
In fact, according to the Energy Saving Trust:
If you replace your old boiler with an A-rated boiler and set of heating controls (you can even operate it remotely via an app on your phone) you could save about £340 and 1,500kg of carbon dioxide a year.
Replacement boiler installation timelines
It’s important to consider how long your replacement boiler installation may take, as some are more complicated than others.
A regular combi swap i.e. replacing your old combi boiler with a new combi boiler in the same location takes on average around a day.
However, if you are converting to a new condensing boiler type e.g. from a combi to a system boiler, it'll probably take a couple of days.
If you live in an average-sized home, see our guide on choosing the best boiler for a 3 bedroom house.
When to replace your boiler?
On average, boilers last around 10 years (that's a decade, to you and me), so if your boiler is getting on a bit, it’s a good indication that it might need to be replaced.
In addition to that, there are a variety of other reasons you may want to consider replacing your boiler, these include:
Old, inefficient Boiler
10+ year-old boilers are G-rated and only have an efficiency rating of around 70%. This means for every £1 spent, 30p is being totally wasted. Modern boilers (like the one's Heatable install), are 90%+ efficient.Beyond Economical Repair (BER)
Often a broken boiler can be incredibly expensive to repair e.g. if components such as a PCB or heat exchanger need to be replaced or repaired, then it may be more cost-effective to get your boiler replaced.Moving your boiler
If you are unhappy with your boiler's current location, then it may make sense to get a new boiler installed in the new location since it will be covered with a brand-new warranty.The current boiler doesn’t meet hot water demands
If you are finding your boiler is failing to meet your hot water and heating requirements, it may be time to replace your boiler with a model with a higher power output.
Have issues with your combi boiler? Read our boiler problems and solutions for quick troubleshooting guidance.
Types of gas boiler replacements
If you are on the hunt for a new boiler, there are three major types to choose from, these include the following:
Combi boiler replacement:
The compact design makes them ideal for properties with limited space.
Do not need a hot water storage cylinder.
Do not need a cold-water tank.
Typically, not suitable for larger properties with multiple bathrooms/or high hot water demand.
It may not be suitable for areas that suffer from low mains water pressure.
Regular (heat only) boiler replacement:
Good choice for properties with multiple bathrooms and high hot water demands.
Ideal for areas that suffer from low water pressure.
Good choice for those with older/traditional heating systems that cannot tolerate high pressure.
Since they require a cistern tank, they demand more space and limit gas boiler replacement options.
A cistern in the attic is prone to freezing during winter and if it leaks can be problematic.
System boiler replacement:
Recommended for properties with multiple bathrooms/hot water outlets.
Does not require a cistern tank in the loft.
Internal components make installation easier.
It may not be suitable for areas that suffer from low water pressure.
It may not be suitable for older central heating systems that cannot tolerate high water pressures.
If you are swapping from a combi, you need to consider where you will store the hot water tank.
Learn more about the different types of boilers.
Got an emergency? If your boiler is busted and you have no hot water, you may be interested in our emergency boiler installation guide.
If you recently found out that you have a condemned boiler it can be a bit of a shock, if you are still considering what to do, refer to our guide on whether to replace or repair your boiler.
Which boiler brands can you choose?
At Heatable, we offer different types of boilers from a range of popular boiler brands, all of which are highly efficient and award-winning or those with an incredible reputation.
The boiler brands we offer include the following:
Worcester Bosch Boilers
Holding a royal warrant, Worcester Bosch is a household name when it comes to boilers.
Several of their new combi boilers have been awarded a Which? Best Buy Award for 10 consecutive years.
Combine that with their excellent guarantee offer, customer service, and easily sourced parts and you have the best boiler brand in the UK.
Read more about Worcester Bosch boilers.
Viessmann Boilers
Dominating the European boiler market, Viessmann has a 5-star reputation thanks to their superb German engineering and simple, crisp designs.
Viessmann boilers have won plenty of awards in the past and have a reputation for being technically superb.
Read more about Viessmann boilers.
Alpha Boilers
Alpha Boilers is a budget-option brand that has been increasing its market share in the UK-wide boiler market over the last few years.
They are a fantastic option for the buyer who is looking for a reliable and affordable heating solution with a whopping warranty (10 years exclusive to Heatable).
Read more about Alpha boilers.
New boiler replacement finance options
If you are unable to purchase your boiler replacement outright, you may be able to take advantage of boiler finance.
If you meet the lender's eligibility criteria, you can potentially pay for your boiler in monthly instalments over 3, 5, 7 or 10 years.
Pay monthly boiler replacement finance summary:
No deposit required (up to 50% optional)
Make overpayments with no penalty
Spread the cost over 3, 5, 7 or 10 years
Interest rates from 9.9% APR
Pay monthly financing plan examples (with our most popular boilers):
Worcester Bosch Greenstar i Boiler Payment Plans:
Fixed prices from £1,950 (get your quote online)
APR | Deposit | Loan Amount Term | Term | Monthly Payment | Interest Payable | Total Payable | APRDepositLoan AmountTermMonthly PaymentInterestTotal Payable |
9.9% | £0 (0%) | £1,780 | 10 Years | £22.98 | £977.36 | £2,757.36 | |
9.9% | £780 (Max) | £1,000 | 10 Years | £12.91 | £549.09 | £2,329.08 | |
9.9% | £0 (0%) | £1,780 | 3 Years | £56.98 | £271.25 | £2,051.25 | |
9.9% | £780 (Max) | £1,000 | 3 Years | £32.01 | £152.39 | £1,932.39 |
Alpha E-Tec Boiler Payment Plans:
Fixed prices from £1,695 (get your quote online)
APR | Deposit | Loan Amount Term | Term | Monthly Payment | Interest Payable | Total Payable | APRDepositLoan AmountTermMonthly PaymentInterestTotal Payable |
9.9% | £0 (0%) | £1,595 | 10 Years | £20.59 | £875.78 | £2,470.78 | |
9.9% | £595 (Max) | £1,000 | 10 Years | £12.91 | £549.09 | £2,144.08 | |
9.9% | £0 (0%) | £1,595 | 3 Years | £51.06 | £243.06 | £1,838.06 | |
9.9% | £595 (Max) | £1,000 | 3 Years | £32.01 | £152.39 | £1,747.39 |
*finance examples are to be used for illustrative purposes only. Get a finance quote online for final figures.
Read more about boilers on finance in our comprehensive guide.
New Boiler Replacement FAQs
Can I speak to someone about buying a new boiler?
We have designed the entire process to be online and make it as easy as possible, however, please feel free to use our online chat function (bottom right) if you have any questions about a new boiler replacement.
How often should you replace your boiler?
If your boiler has been well maintained i.e. serviced annually and is in good shape, it can last between 10 and 15 years.
However, if your boiler is very old and is a non-condensing G-rated model, it may make financial sense to have it replaced sooner.
For example, according to the Energy Saving Trust upgrading from an old G-rated boiler to a modern A-rated boiler could save you as much as £300 a year on your bills.
Related reading:
Are there government grants to replace boilers?
At present there are two main government boiler schemes available in the UK, these are the Energy Company Obligation Scheme (ECO) and the Boiler Upgrade Scheme (BUS).
The ECO4 scheme is only offered to those who meet the strict eligibility criteria, while the BUS offers £5,000 towards the cost of installing renewables only, which only includes biomass boilers i.e. it can’t be used for new gas boilers.
What is the average cost of a new boiler replacement?
There are many variables that can impact the final costs including the type of boiler, the model of the boiler and whether you want your boiler moved to name a few.
However, a standard like-for-like combi boiler swap/replacement costs anywhere from £1,500, all the way up to £3,500, including installation, depending on the type of boiler you'd like, its warranty length, how complex the required installation is, and what the labour costs are in the area which you live.
How to get a new boiler 👻
You may need a new boiler.
You may need it fast and with affordable monthly payments.
You may even need it from a company with top-end local engineers, with 10,000 Trust Pilot reviews to back them up. Plus a Which? Trusted Trader award for good measure.
You may need a new boiler quote from us, Heatable 😘
