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How to buy a new boiler

A new boiler is one of the most important purchases you'll make for your home. In this guide, we'll walk you through what needs to be considered and the choices available.

When the time comes to replace your central heating, you may be surprised at how much you have to consider. Help is at hand as we run through everything from the different heating types and brands to even the best place to position it in your home.

Do your research

Research is key if you want to know what central heating system is right for your home. Narrowing down the many choices available, from the boiler brands and models available should be your first port of call, especially if you want to make the most efficient and cost-effective choice.

Choosing the right appliance can also save you money thanks to newer technology having a higher energy efficiency rating, so you're paying less in energy bills.

What is the right type of boiler?

There are three main types of central heating to consider, with each suited to differing levels of heating demand and property type.

Combi boiler

Today combination boilers (or combis) are the most common type. They are often smaller than other central heating systems and combine two functions, heating and hot water.

Water is heated directly from the mains when a tap or appliance is turned on, so there’s no need for a hot water storage cylinder or a cold-water storage tank. As well as taking up a small amount of space, combi's are able to heat up a small amount of water incredibly fast.


System Boiler

Systems are very similar to combi, as they both are supplied water from the mains and the heating components are built into the unit. While they don’t need a cold-water tank, they do require a hot water cylinder to be installed to store heated water.


Regular Boiler 

This central heating system creates hot water for the central heating system and stores the rest into a hot water cylinder. If there is enough stored hot water, you can use multiple taps at once. This heating unit also requires a cold-water tank (often found in the loft). They’re a good choice if you have older radiators as a system or combi with higher water pressure could damage them.

Working out your heating and hot water output

Working out what type of boiler you need has a lot to do with the kind of property you have and the number of people living there. While an output rating that is too low will struggle to provide the necessary amount of hot water for your needs, one that is too high could lead to soaring energy bills. 

Below are three different property types and the heating systems that are best suited:

Small terrace house, 2-bed flat or bungalow 

This type of property would usually have up to two bedrooms, 1 bathroom and up to 10 radiators. For this, an output of between 24-27kW is required. A combi boiler is recommended as it will provide hot water quickly and, as it doesn’t require a water tank and has less pipe work, it’s perfect for tight spaces.


Medium terrace or semi-detached property

This type of property usually has between 3-4 bedrooms, 2 - 3 bathrooms and up to 15 radiators. To meet this demand, an output rating of 28-34kW is needed. A high output combi could deal with this (especially if you don't have a lot of spare storage space) but a system boiler is the best option, as its hot water cylinder stores extra hot water, giving you a constant supply to meet the demand.


Large semi-detached or detached house 

This type of property will usually have 4 or more bedrooms, 2 or more bathrooms and up to 20 radiators. Such a large property requires an output of between 35-42kW. While a system boiler could still be the solution, it may be necessary to go for a more substantial regular boiler with a hot water cylinder and enough room in the loft to store a cold-water storage tank.

Where to install your boiler?

Today’s boilers have been designed to be far more compact than previous models, allowing them to be mounted conveniently to walls. Freestanding units are usually narrower, meaning that they can be fitted between kitchen units. 

It is vital that gas and oil burners are installed onto an external wall, so that a flue can be fitted to emit potentially harmful waste gases outside. Electric central heating doesn't a flue as it doesn't produce waste.

If you are thinking about moving your boiler to a different location, you can read more about the costs associated.

Where to buy a boiler from?

We offer a wide range of brands, all of which offer a range of different features and up to 10 years manufacturer warranty. So, "How much to buy and install" differs from brand to brand, but generally, prices are:

Combi Boiler -   £1,600 - £3,200
System Boiler -  £2,300 - £4,000
Regular Boiler -  £2,000 - £3,600

To make sure that you choose the right central heating system for your home, it's highly recommended that you first undergo a home survey with a Gas Safe registered engineer. This can be completed in person or through a video call. 

They will perform a visual check on your current central heating system and fill out a quote booklet with a recommended boiler that will be a perfect fit for your home.

How can I fund my boiler?

There a number of payment options available to help you pay for a new heating unit. You can purchase a boiler on finance should you need to replace quickly (or due to an emergency).

We offer a range of finance plans, including interest-free, Buy Now Pay Later and 6.9% APR Representative options - ranging from 12 to 120 months. Of course, you can always opt for a straightforward cash purchase, which is payable on installation.

Looking after your boiler

Now that you have your brand-new central heating system, you'll want to look after it. The best way to avoid being left in the cold is by investing in one of our various boiler care plans. By making monthly payments into a plan, you won't have to pay for call out charges or, depending on the level of your cover, any of the potentially costly work carried out. You can just sit back, relax and stay warm knowing we've got you covered.