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What Boiler Size Do I Need

When it comes to installing a new boiler, you’ll need to understand what size boiler you’ll need. There are many factors that determine the size boiler you choose and you’ll benefit from professional help when looking for a new boiler.

The reality is that you will need a certain boiler size and type to ensure you are able to meet your water demands. However, opting to use a professional installer will ensure you benefit from their advice and guidance when choosing your boiler. While every property is different, you’ll need to consider several aspects to determine your boiler size.

So, you will need to think about your living situation and whether you live with a large family or alone. Consider how many people use your bathroom or bathrooms at any one time. Creating a user profile that is based on your needs, you’ll be able to identify your water demands.

What Does Boiler Size Mean?

This is not about the physical size of the boiler but the actual power output of a boiler. This is measured in KW (Kilowatts) and this will be an important consideration when it comes to determining the type and model of boiler you require.

How Do I Determine The Right Boiler Size?

To identify the right boiler size, you will need to consider these following questions:

  • What boiler do you currently have? Is it an open vent, combi or system?
  • Are you considering changing the type of boiler completely? This might involve moving from a combi to an open vent?
  • Do you live in an old property or a modern property that has recently been constructed?
  • How many bathrooms do you have?
  • How much demand is there for domestic hot water?

If you pick the wrong boiler then it could take longer to heat up your property as well as your hot water cylinder if you have one. If it’s too big, you’ll have the problem of using more gas than required and with that comes an increase in energy use and expenditure. If you have the answers to the questions above, then it’s time to speak to the experts who can help you to find the right boiler for your property.

What Type Of Boiler Do I Need?

There is no specific type or size of boiler that is better than another but ensuring you choose the right boiler is still important. For modern condensing boilers, the boiler size is modulated in KW which is dependent on the load and that enables a high level of efficiency.

What Is Boiler Modulation And What Does It Mean?

Boiler modulation is the way in which the boiler alters its output to meet the heading load. As an example, if the demand for hot water changes or you opt to have another radiator fitte, the boiler will have the ability to alter the output in order to meet the new heating load. This can help to enhance the lifespan and the quality of the internal components.

So, if you live in a modern property that has three bedrooms and eight radiators, each radiator will have an output of around 1.5kw. If this is multiplied by eight then this means that the overall output will be a12kw. As a result, you should opt for a boiler that has a modulation range of 1-6 which will mean that it has the ability to operate within a range of between 4.8kw and 29kw. Boilers are designed to modulate and so, when you are considering the size boiler that you need, you’ll need to understand how modulation plays a part in the entire process.

Where Can I Install My Boiler?

So, along with asking what size boiler you need, you need to think about its location because you need to make sure it is suitable to fit into the desired installation location. You could opt to install it in a kitchen cabinet, loft or the airing cupboard

How Do Radiators Determine The Size Boiler I Require?

The majority of small properties such as apartments or one bedroom houses will have up to ten standard size radiators. The numbers need to be worked out in relation to your overall energy count. If you have a larger property that is older then there will be a larger hot water demand as the bigger radiators would need around 2kw.

What Other Considerations Are They When Determining Boiler Size

As discussed, there are a number of different aspects to your property that need to be identified before choosing your boiler size. One thing that will need to be considered is the type of boiler that your property currently has installed. If you’re choosing to make the switch from an open vent to a combi, you’re going to need to ensure that your pipework is suitable and safe. Along with this, you will need to take caution, especially if you are choosing to move from a non-pressurised system to a pressurised system as the pipework will be buried in concrete.

You can opt for a combi boiler which is a combination boiler. This type of boiler combines heating and hot water into one single unit. They work as and when you need them and so, there is no need to have separate water storage cylinders installed.

If you choose to install a sealed system boiler, the heating and hot water components are built into the boiler. It needs a pressurized unvented cylinder for storing hot water. This is different to a conventional boiler as you won’t need a cold water tank installed in your loft or attic.

Regular boilers are also known as Open Vent, Conventional or Standard Boilers. These all need a cold water tank as well as a hot water cylinder, these are usually stored in the attic and airing cupboard.

There are many things to consider when selecting your boiler size. Although we have covered the basics, there is more to think about and that is why you’ll need to speak to the experts. There are many different boilers on the market and they are all different in their own way. However, having a clear understanding of what you need will enable you to create a list of boilers that are suitable for your property and your needs.

Your boiler is an integral part of your home and is something that you will need to research and understand fully before making your decision.

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