Bind – Gas Safe Registered Boiler Engineers, Somerset & Wiltshire

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Selecting the right size boiler is a pivotal step in ensuring your home stays warm and comfortable without breaking the bank. It’s not just about physical dimensions, but about finding the perfect match for your property’s unique heating needs. In this guide, we’ll break down the process into easy steps to help you on your way to deciding what’s best for you. So, let’s dive in.

Checking Your Water Flow Rate

Before diving into boiler sizes, it’s crucial to check your water flow rate. This simple test involves finding an unrestricted mains supply, like an outdoor tap, and timing how long it takes to fill up a 5-litre bucket – we’re looking for a decent 15/m flow which is a suitable flow rate for a system and combi boilers. Anything below 10 litres per minute is considered low pressure. A reading between 10-15 litres per minute is average and a flow above 15 is considered good.

Boiler Size and Modulation – What Kw Boiler Do I Need?

Boiler size, measured in kW (Kilowatts), refers to the output of the boiler in terms of heat energy. This determines which boiler is the right fit for your property. Remember, bigger properties with higher hot water demands typically require a larger kW output. Today’s modern condensing boilers also have a ‘modulated’ output, which means they adjust their energy output based on the load, ensuring superior efficiency.

Boiler Sizing By Property Types

Property Type No. of Bedrooms No. of Radiators Recommended Boiler Size
Apartment/Flat or House with up to 2 bedrooms 1-2 Up to 10 24kW-27kW
Apartment/Flat or House with 2-3 bedrooms and 1 shower 2-3 Up to 15 28kW-34kW
House with 4+ bedrooms and 2 showers 4+ Up to 28 35kW-42kW


The Role of Insulation

In addition to the size of your property and its heating demands, it’s crucial to consider the insulation of your home. Well-insulated homes retain heat more effectively, reducing the strain on your boiler and ultimately leading to energy savings. Adequate insulation can make a significant difference in the performance and efficiency of your heating system. So, before making a final decision on the boiler size, it’s worthwhile to evaluate and, if necessary, upgrade your home’s insulation for optimal results.

The Pitfalls of Choosing the Wrong Size Boiler

Choosing a boiler that’s too large or too small can lead to wasted energy and higher bills. It may also result in longer heating times. Fortunately, modern boilers are designed for efficiency, so it’s essential to match the size to your property’s requirements.

Let Bind Help You Find the Perfect Fit

If you’re still uncertain, don’t worry. Our team of experienced Gas Safe heating engineers with years of expertise is here to assist you. Use our online boiler quote tool, answer a few quick questions, and our intelligent system will recommend the exact size boiler tailored to your needs.
Bind’s next-day boiler installation provides homeowners with a quick and super-simple solution to their heating needs, without the hassle of waiting weeks to get a new boiler installed. We also offer some amazing after-sales boiler servicing and system checks too!


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