How much is a new boiler?

Boiler Installations from Avenue Heating

What is the cost of a replacement boiler in 2021?


There are various reasons you may consider replacing your boiler, whether that be due to moving house, extending your property or adding a new bathroom. Trying to work out costs and budget for your new boiler can be difficult due to there being so many variables and factors that dictate what boiler is most suitable for your home, such as the type of boiler, the size of boiler, the type of system you currently have and what are your plans for your property, both long and short-term.

In order for you to have comfortable levels of heat and hot water in your home, it is likely that your boiler is the most important item providing this and it is vital that you choose the right boiler for your home’s requirements. Based on a multitude of brands, sizes and types available, the cost of just a boiler on it’s own can very from as little as £400 for the cheapest boiler, right up to around £3,000 for a top of the range, quality boiler, such as a Viessmann Vitodens 222. Considering that about half of all of what each of us spends on our energy bills from our boiler usage, having a more efficient new boiler, may mean that you are able to make savings against your energy costs though energy savings. For example a detached home, with a energy rated G boiler, could make savings of around £350 a year. So holding out for your inefficient boiler to last another year, when you add on the cost of any repairs it may need during that time, may end very quickly working out economically unviable to keep it!

When your new boiler is specified, it will have been done so by carrying out an assessment of a number of factors, such as, your water demands, how may people living in the property (even their ages!), your plans for the property, such as future extension plans, the available water pressure from the mains water supply and any requirements you may have personally, such as having the ability to provide a number of bathrooms with water at the same time. In the UK the most popular boiler to be fitted is a combination boiler. A combination boiler, otherwise known as a combi boiler, provides both heating and hot water instantly on-demand from a single boiler unit, most commonly wall-hung. Having a combi boiler fitted in your home has many benefits; they are efficient and very good space-saving solutions and mean there is no need for a separate hot water cylinder. The downside for combi boilers, is that they struggle if there are multiple bathrooms trying to use hot water at the same time. This is due to combi boilers having a limit to the amount of hot water that they can provide at any given time. If you have a home that has more than two bath/shower rooms, it is most likely that a system or conventional boiler is more suitable. For more information about the different types of boilers please click here!

When we talk about the size of your boiler, what we are referring to is the power output of a boiler, measured in kilowatts per hour (kWh), meaning the larger the kW the great the capacity for that boiler to produce heat. All boiler manufacturers offer a whole range of different models of boilers, with different outputs, sizes and pros and cons for each. This is where it is crucial to get an experienced engineer to assess your property and provide you with enough information to make an informed decision as to the exact boiler that is most suitable for your home. Seeking out an experienced engineer is so crucial here because if you size your boiler too low or too high, both can have a negative affect on the performance of your system, the obvious being that your home won’t heat adequately. The less obvious, if your boiler is over spec’d, will be that your boiler will have to work harder to modulate down or even burn unnecessary fuel, defeating the object of choosing an energy efficient boiler! The only time that you should look at installing a boiler that is too large for your property, is if you are planning on extending your property in the short to medium term, which will mean you install a boiler that can handle your future requirements.

When looking at installation costs for your new boiler, a replacement boiler installation, on a like-for-like basis for your existing boiler, will be the most cost effective way to go. If you are wanting to change the location of the boiler or alter pipework for any reason, this will increase the cost of the installation. A request to have a combi boiler fitted is a common one, however, it can be a complicated and expensive process. In order to have a combi boiler, your water tanks will need to be removed, pipework altered, possibly a new gas supply will be needed and new controls are likely to be required. This additional work will take your average boiler replacement (including VAT) from around £3,000 to £4000, depending on whether a new gas supply is required, it could be anything from £200 (if the gas meter is close to your boiler), right up to even an additional £1000 (if your boiler is in your loft, for example).

If you decide to install your boiler in a different location, it may mean that you require a vertical flue, which could add an additional £300-800. A flue is a large pipe that comes out of the top of the boiler and take the products of combustion from your boiler to the outside, working much like a car exhaust. In the vast majority of time, a flue can be terminated horizontally, but if a vertical flue is required, it will take more time and money. Another flue consideration, is whether you need a plume kit. A plume kit, is an extension to your flue that helps to direct the products of combustion of your boiler away from windows, doors or your neighbours property. A plume kit could cost an additional £100-150. A qualified gas engineer will be able to advise you here to ensure that you comply with Gas Safe regulations.

Along with the costs highlighted above, there are also optional extras, such as if the system needs to be flushed, whether a Smart control is opted for, such a Nest thermostat, a magnetic filter is opted for and if an extended warranty is selected. Each of these could be anything from £200 up to around £1200, if you have a large property that requires a full heating system flush (also called a power-flush).

At Avenue Heating, we have been replacing boilers for over fifteen years and can promise the service you will be provided with, the attention to detail and expert knowledge we have, will leave you with feeling that you have been provided with a high-quality, professionally installed boiler.  If you would like to discuss your new boiler requirements with a free no obligation quote, CLICK HERE or call us on 0203 137 3333 to discuss your specific boiler needs.

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