Boiler Replacement Guide | Get help arranging your new boiler installation

Quick guide summary

How do I go about arranging a replacement boiler? We give you all the information you need.

We give you six easy steps to arranging a replacement boiler, from working out which type of boiler you have to getting a price and finding someone to fit it. Just a little research will help you to find the right product, the right installer and get the best value. We guide you through the key topics and tools on our website to get you answers that suit your circumstances. Once you are ready, we help you decide who you want to fit your boiler. Do you go with a national company, a local installer or do it all online? We cut through the industry fog and give you four options based on industry operator along with the advantages and disadvantages of each.

Overview of boiler replacement

Follow our step by step guide...

Knowledge is power! We equip you with the knowledge to find the best boiler and the best person or company to fit it. Follow our 6 easy steps to researching your replacement boiler, getting a installation price and finding an installer.

Review different industry operators

You can use a national company, regional company, local heating company, buy a boiler online, unknowling use a sub contractor network or go with a local sole trader. We review all the market operators and the advantages and disadvantages of each.

How to use this Guide

Follow our 6 steps to a replacement boiler

Review industry operators

Consider pros and cons

Decide who is best for you

Six easy steps to a successful boiler replacement

Follow our step by step guide to arranging your replacement boiler installation. If you know which boiler type you have and which boiler type you want and where, then you can skip Step 1 and Step 2. You might want to take a side step at Step 3 to our Boiler Information Hub and research related topics such as heating controls, accredited installer schemes and flexible ways to pay.

Open up a new tab for your research & return to this page

1) Do you have a combi, heat only or system boiler?

Use our Guide to Boiler Types to work out which boiler you have - combi, heat-only or system

2) Do you want to change boiler type or move location?

Use our Guide to Boiler Swaps, Moves & Changes to work out whether you want to change to a new boiler type and the pros and cons of relocating it

3) Get the knowledge you need to find best value

Use our Guides to Combi Boiler Prices; Heat Only Boilers Prices; System Boiler Prices to compare boilers by price and warranty. Research other topics via our Information Hub such as Flexible Ways to Pay for a new boiler.

4) Get a fitted price with our quote calculator

Use our Boiler Quote Calculator to get a bespoke estimate for a fully fitted boiler installation (i.e. includes materials & labour). For full central heating system costs with radiators try our Guide to Central Heating Costs.

5) Find a local heating company & book a survey

Use our Find a Local Heating Company search to book a boiler survey. NB if you use the Boiler Quote Calculator under Step 4 you will automatically move onto our local company search.

6) Review different types of installers

You can go with a national company, regional company, local independent company, sole trader or a sub contractor via an online company. Review all the market operators below and the pros and cons of each.

Which type of boiler installer should I use?

We have grouped the different types of boiler installer together under four headings according to their characteristics: 1) National and Regional Companies; 2) Local Independent Companies; 3) Sub contractor networks (including online companies); and 4) Sole Traders. There are advantages and disadvantages to using each. The right operator for you will be based on many factors and at the end of this section we give you some guidance based on your priorities and common perceptions of the market.

National and Regional Companies

British Gas is probably the only national company that employs the majority of its installation workforce. There are a number of large regional companies that operate in a similar way.


  • They are easy to contact with long call centre opening hours
  • They have a large network of employed surveyors who can call at a time to suit you
  • They offer flexible ways to pay and spread the cost
  • They can offer cover for your whole central heating system to ‘top up’ the boiler manufacturer’s warranty


  • They are often more expensive because they employ surveyors/sales persons as well as installations teams
  • You are unlikely to speak to the same person twice
  • If the surveyor is not an ex-installer, the quality of advice will not be as good as someone who has experience in installing boilers and heating systems

Local Independent Companies

Local heating companies are often well established, family run businesses in your area. Many employ between 2-8 gas engineers to install and repair boilers. (Find your local heating company on our network of installers).


  • Local businesses often deliver a very personal service with the business owners involved in the day to day running of the operations
  • They keep costs down by the business owner or one of the installers carrying out the survey
  • Many now offer flexible ways to pay via a finance facility, the same as regional and national companies
  • Many are accredited with boiler manufacturers and can offer free extended boiler warranties
  • Some of the larger independent companies also offer heating system cover to ‘top up’ the boiler cover from the manufacturer
  • They are passionate about their business and provide job opportunities in their area


  • Their office hours will likely be shorter
  • They may not be able to carry out daytime quotes, but can often attend at evenings and weekends

Sub contractor networks

The industry has evolved over the last 10 years and sub contractor (sometimes self-employed) networks offer a way for heating companies seeking to geographically expand their boiler installation services to reach further afield. These networks offer flexibility as sub contractors can be called upon during busy times but let go during the summer period. 2017 saw the launch of some interesting new business models in the heating industry, primarily that of ‘online quoting’ I.e. a surveyor never visits your home. A quote is generated based on information you have submitted online. This is usually followed by a phone call and then by you submitting some photographs. Other models provide prices in the same way but from a network of different installers.


  • Like the established national and regional companies, they offer long call centre opening hours
  • Similarly they employ surveyors to carry out boiler quotes at a time to suit you.
  • They offer flexible ways to pay
  • For time-poor individuals, online quotes are quicker than getting three companies around to quote
  • They often offer next day boiler installations


  • Surveyors travel large distances to carry out boiler surveys. This makes the job more expensive.
  • Sub contractors can also travel large distances to fit a boiler, making job overheads high
  • With so much of the job carried out by parties outside your area, it does not support your local economy
  • Getting a return visit in the event of a problem may prove more difficult as someone will likely have to travel a long way to attend
  • For online quotes, photographic evidence is usually required which may alter the online price
  • When jobs are priced without a site survey there is a risk of under-quoting. This could lead to corner cutting by the subcontractor in order to finish the job in the time they are given, not the time it would normally take.
  • A price orientated network only triumphs the cheapest, not necessarily the best value.


Sole traders comprise either a lone installer or installer + apprentice. They do not have premises and rarely any kind of administrational support. They work from their vans.


  • Often cheaper than regionals and nationals
  • A good local fitter will deliver good value


  • More difficult to get hold of as no office support
  • Not likely to offer finance
  • In the event of sickness, your job will be postponed as there are no other fitters available to step in

Top Tips - How do you make a choice?

It depends on your priorities and perceptions, for example:
  • You like the sense of support you get from a national or regional company
  • You like to use local businesses and support the local economy
  • You think only big companies offer longer boiler warranties and/or finance
  • You think using a sole trader will be cheaper
  • You think bigger companies are more reliable
  • You need a boiler installed tomorrow!
  • You want to cover your boiler and heating system for breakdowns after its installed
All of these are important factors in your decision making, however it is rarely quite so black and white:
  • All national, regional and some local companies have an office facility whereby you can always contact someone and get support
  • Supporting local businesses is very important and many have invested in their businesses to operate like much larger businesses, such as using cloud-based job management software.
  • Many local companies are now FCA registered and can now offer ways to spread the cost of a new boiler via a mainstream finance company
  • Many local companies are ‘registered installers’ with the main boiler manufacturers – such as Vaillant, Worcester and Baxi. As such they have undergone training on their boilers and can offer long warranties to their customers, sometimes longer than the national and regional companies.
  • Sole traders and local companies are often cheaper, although many regional and national entities have become more competitive in recent years.
  • Online quote companies are installing boilers faster than ever. This might be important in the middle of winter, but for the rest of the year it’s still best to get three quotes from people coming into your home.
  • Many national and regional installers offer free 'top up' cover for the rest of your system for the first year. However this is not as valuable as you think, particularly if there are many hidden exclusions. You can buy comprehensive cover from a mainstream provider such as Aviva, British Gas, Corgi or Homeserve and the package might be better than that on offer as part of the installation offer (see our Guide to Boiler Cover for best buys and hidden exclusions to look out for). Some local companies offer top up cover so that you can use the manufacturer's warranty for the boiler and get the rest of the system covered separately.

What would you like to do next?

Use our calculator to get an estimate of boiler installation cost


When to swap, change or move your boiler


Ways to pay for your new boiler installation


Other useful guides

Book a survey with a local heating company


Manufacturer smart controls v Nest and Hive


Guide to Heating Controls