Which new boiler should I buy?

Boiler Installation

October 29, 2021

Which new boiler should I buy?

Planning to buy a new boiler?

Or maybe you are replacing your existing model. Whatever the reason, choosing the correct boiler is essential to ensure that you find one which will suit your home and provide efficient heating year-round.

When it comes time to purchase a new boiler, many things need consideration before making that final decision on which one will be best suited for your homes, such as the price of the boiler, energy efficiency and the size of the boiler. In this blog post, we are going to focus on choosing the correct size of boilers for your home.

Choosing the Correct Boiler Size

To ensure you purchase the correct boiler  size for your home, there are a few things that need to be considered before making any purchases: 

1) To find the correct boiler size, you need to know how much heating capacity your house needs. The first step in finding out this information is to measure the square footage of the floor space. If you are not sure which method works best for measuring then follow these simple instructions:

  • Take a tape measure and find the length of each wall in inches. Multiply that number by itself to get square footage for just one room then add together all the rooms where you want central heating installed. This will give you an approximation of how much space there is under your roof which needs to be heated throughout the winter months. Then multiply the total of these room measurements by the ceiling height.

This will give you a rough idea of how much heating your home needs and whether or not it is feasible to have central heating installed, but still won't determine which boiler size is correct for installation in your home. It is important to note that boiler size cannot be determined by the square footage of your home. You can use this method to get a rough idea, but you need to bear in mind it will not be correct and should therefore only be used as a guide for sizing. For a more precise calculation, we suggest you contact a local plumber who will be able to provide you with the correct information.

2) If you are looking for a boiler size to use in your home, the ideal option is the "A-rated" model. This means that it has an energy efficiency rating of 90% or above and will be able to provide efficient heating all year round without costing too much on bills. If an average-sized family of three or four people is living in your home, likely, a boiler providing between 14 and 20 kilowatts (kW) is needed for central heating. However, if more than four people are living in your

3) Another factor that needs consideration when choosing the correct boiler size is the cost of installation. If you are on a budget, it may be worth considering getting a smaller model installed as this will help keep costs down and still provide efficiency all year round. The most common type of heating appliances used in homes today are either Condensing or Non-Condensing boilers but there's also room heaters that are used to heat just one room in the home. Condensing boilers are known for their high levels of efficiency and ability to provide year-round heating. However, they do come at a greater cost than Non-Condensing models which can be significantly cheaper but still provide good central heating.

How Much Does it Cost?

A new boiler may seem like the last thing you need right now, but it is an investment that will last for many years to come and save you money on bills along the way. The cost of a new boiler can vary depending on which type you choose, whether or not installation is required and the size of your home. A simple online search such as "heating installations" in Google should provide results so you can find a local plumber to give you an accurate quote. It is important that you do not attempt the installation yourself and always consult with a professional so as not to void any warranty on your new boiler should something go wrong after it has been installed.

Installing the Boiler in Your Home

A boiler's location in your home is just as important as its energy efficiency rating. Placing a boiler too far away from the point where hot water will be used can affect performance and waste money on bills, so it needs to be tucked away in an area with easy access to cold running water for when you need more hot water during showers or baths. A good example of this is in the basement or lower ground floor, where you can easily run a pipe to feed water into the boiler and access cold water for flushing out waste on demand.

It is also worth having someone come and survey the area of your home where you plan to place a new boiler. They will be able to advise on how much space there is for installation, which type would work best in that location and what else needs to be considered when choosing the correct size.


Choosing the correct size is essential if you want your boiler to last for many years and provide efficient heating throughout, but it's also important that you get advice from professionals before finalising any purchases. Whether or not central heating will be suitable for your house depends on many different factors and should be assessed by a professional first to avoid any problems down the line.

Our professionals at RARE Heating and Plumbing Services will be happy to help you find the correct boiler size and give you a quote a new boiler installation qoute in Marylebone. Give us a call today to find out more about our heating services in Camden, Hampstead, Golder’s Green, Westminster, Highgate, Maida Vale or any other part of London. We offer a timely, fuss-free 24-hour service delivered by professional engineers who are fully licensed and insured.

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Have a look at our outstanding reviews to see how we treat our customers and their homes.

We had a problem with our boiler and complex heating system that other plumbers refused to touch. Paresh took it on, and fixed it very quickly. The visit was swift and easy, and he was very sensitive to our shielding requirements.
Michael Quicke
Having previously used Rare to do a full system installation, including new heaters, storage tank, new boiler install, bathroom fit & kitchen appliance install and new piping throughout the home, I called upon them again to service our boiler this winter. Pareshs engineers were punctual, they called 15 mins before arriving and methodically explained the work they work going to carry out, serviced the boiler, drained the radiotors and also treated them. They ensured everything was fine and more importantly assured us the system was in perfect order for the winter and made a few adjustments. More importantly then that the engineers completely cleaned up and washed down the working areas leaving our home spotless. Highly recommend this company for all your plumbing needs.
Amit Halai
Paresh is unusual for a London tradesman -- he comes when he says he will come, he charges what he says he will charge, and the workmanship is always first class. I cannot recommend him highly enough.
James Robertson
Helped me with underfloor heating issue - I am so lucky to have found them! Great customer service, so knowledgeable - can't recommend them highly enough.
Becky B
I called Rare on Christmas Day with an urgent boiler problem. The team was very responsive, professional and polite - the issue was fixed quickly and fortunately they saved us from spending Christmas in a cold home with no warm water! Thanks again!
Yorick Duizendstraal
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