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Boiler calculators – A guest post from BoilerGuide.co.uk

At Best Heating we have our BTU Calculator to help you to get a precise calculation of the size and output of the radiator or heated towel rail you’ll need to heat your space. But what about your boiler? Do you not need to know how big and powerful that needs to be too? – Do you not need a ‘boiler calculator’?

This guest post from our heat loving friends at Boiler Guide outlines what you need to consider before purchasing a new boiler and what you should get together before you part with your cash.


Boiler Calculators

Heating boiler

Purchasing a new boiler can seem like a daunting task – it is after all an investment, so making sure you get the best option for your money is essential.

Luckily there are handy online boiler calculators to make this easier! Here’s our top tips on using these calculators and investing in the perfect boiler to keep your home cosy and your heating bills low.

Why does getting the right size of boiler matter?

If you have the wrong size of boiler installed you may find it over or under heats your home.

A boiler which is too small won’t be able to provide a sufficient amount of hot water for your radiators and taps – especially if you have a large property or high hot water demand.

On the other side of the scale, a boiler which is too large for your home will likely be wasteful, producing more heat that you could use. Not only will this hike up your energy bill, it will also mean your home is producing higher levels of emissions.

Factors to consider when choosing a boiler size

There are plenty of boiler calculators online (like this one) which will determine the best size of boiler for your needs. Here’s the information you’ll need to have handy to use them and why each question matters.

Insulation and heat loss

Unfortunately the UK is known for its leaky housing stock, but insulation can help to reduce the amount of heat lost dramatically.

By entering these details into a calculator, it can better understand how much heat may be lost from your home, and therefore how much a boiler would need to compensate for this.

It’s definitely worth looking into insulation for your property before investing in a boiler, after all heating your home to then lose it through your walls, floor, roof and windows/ doors is rather counterproductive!

Property type and size

This allows the calculator to identify how many external walls you have in the property and how large they are. Some calculators will ask you specifically for the number of walls, so make sure to identify if they are asking for all types of walls or external walls only.

Taps, baths and sinks

Your boiler will likely have 2 main jobs; supply hot water to your taps and also your radiators.

Simply count how many sinks, baths and showers you have (although some calculators may ask you just for the number of taps overall). You may also need to state how high your hot water demand is, so at this point it’s also worth considering if this is likely to change in the near future.

Making the correct calculations

There’s two main types of boiler calculator; quiz style online versions and a pdf sheet you can print to record and calculate figures manually.

Using more than one calculator and comparing the results can give you a better indication of a ballpark boiler size, so it’s worth trying multiple calculators.

This can be handy to work out rough costs in the planning stage, but we recommend you consult a qualified engineer before going ahead with a boiler installation, as they will be able to advise you best.

complex matahematics on a blackboard

Making your home heating as efficient as possible

Having a suitably sized boiler installed is just one way to ensure you are keeping your property’s heating as efficient as possible. Here’s some tips on making the most of your boiler and the heat it produces.

Have your property insulated to reduce heat loss

As we mentioned earlier, having your home insulated is one of the best ways to make the most of the heat generated by your central heating system. A good place to start is insulating your roof (cause of around 25% of heat loss) and also walls (35%) as they can provide the biggest benefits at lowest payback times.

Ensure you have the right radiators

The boiler size recommended by a calculator should be adequate for the number of radiators needed in your entire home but figuring out which radiators to opt for in each room is the next step. You can use BestHeating’s BTU calculator to do this easily and it will indicate the BTU (British Thermal Unit) / watt output you will need from a radiator (or radiators) to heat the room adequately.

Install a smart thermostat for more control

If you want to take full control of a new boiler or central heating system, smart thermostats can be a great option. They allow you to optimise your heating remotely, so you only use it when you need it. This can help to reduce wasted energy and cut your bills, so whilst they are an upfront investment they will pay for themselves over time.

Get your boiler serviced each year

Finally, and most importantly if you opt for a gas boiler, is an annual service from a registered engineer. Not only will the engineer make checks to ensure your boiler is working safely, they can also spot any problems (or signs of future problems) that are causing the boiler to be less effective.

So there you have it, a simple and straightforward guide from the experts at Boiler Guide.

Boiler Guide

BoilerGuide.co.uk is a go to resource for information and advice on boilers, central heating and energy savings. It also puts homeowners in touch with registered heating engineers to take the hassle out of finding reputable local companies.

Go and pay them a visit and discover help and advice on a load of home heating issues.

Stay safe and happy heating.

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