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Combi Vs Conventional Boilers: Pros And Cons

Combi vs Conventional Boilers: Pros and Cons

Choosing the right heating system for your home is crucial. Getting this right will mean you do not overspend on energy bills and have a system that keeps up with the demands placed on it. For most homeowners, this choice comes down to having a combi or conventional boiler fitted. While you might think that they are mostly the same, they are in fact very different. This means that finding out more about them before deciding which to install is a must.

But what pros and cons do each come with?

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Combi boilers explained

Before we look at the pros and cons of a combi boiler, it is first helpful to understand how they work. This is because you can then begin to decide if it is right for your needs. In simple terms, this type of boiler provides on-demand heating and hot water. It does not come with any tanks or cylinders, as everything it needs to work is found inside the boiler. Top brands for combi boilers include Worcester Bosch, Baxi and Vaillant.

But what are the advantages and disadvantages of these boilers?

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Combi boiler pros and cons

Let’s start with the positives this type of boiler comes with! As it does not need any external tanks or cylinders, it is a very compact heating solution. This makes it ideal for properties where space is at a premium. The on-demand nature of combi boilers means that you always have hot water when you need it. These boilers are also pretty simple to install and offer decent value for money. When combined, this can make them better if you are on a budget or need your boiler installing quickly.

But what cons do they come with? Perhaps the biggest is that they are only really suitable for small to medium-sized properties, with only one main bathroom. Larger homes or those with multiple bathrooms will probably find a combi can’t meet their hot water requirements. Combi boilers also need decent water pressure to work efficiently. For this reason, they are not ideal for homes with low water pressure.

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Conventional boilers 101

Now we have looked at combi boilers, we turn our attention to conventional boilers. As the name suggests, this type of boiler was the sort most people had, before the combi came along. The difference between the two lies in how they work and what they come with.

A conventional boiler, for example, will need tanks in your loft and a hot water cylinder to work. But why is this? In simple terms, the cold water tank in your loft delivers water down to the boiler when needed to be heated up. After this is done, the hot water is kept inside the cylinder to be used. As with combi boilers, the best manufacturers include Baxi, Vaillant and Worcester Bosch.

Conventional boiler pros and cons

This type of boiler has a few plus points to recommend it. Firstly, it is the best choice if you are replacing an old conventional boiler. This is because the pipework is already in place to connect another conventional boiler up easily. These boilers also have high-efficiency levels which are important for many homeowners. Due to their design, they are also great for meeting the hot water demands of larger properties, larger families or homes with multiple bathrooms.

But what downsides do they come with? The first is that they do not give instant hot water in the same way as a combi. As the water has to be heated from cold first, this can mean a delay in getting hot water sometimes. If you need all the pipework fitting to connect these boilers up, this can be costly and long-winded. Conventional boilers also need lots of space to house the tanks, cylinder and boiler. This is not always feasible in every property. Lastly, the cylinders these boilers use need very good insulation to keep water warm. This insulation can be expensive to have fitted, which could put some people off.

Combi or conventional boiler - which is the best choice?

The short answer is that there is no ‘best’ choice as such – it all depends on your personal circumstances and what you require. A combi boiler is better for smaller homes with only one bathroom, for example, or those who need on-demand hot water. They can also be best for properties who do not have space for conventional boilers or are on a tighter budget.

Conventional boilers are often best for larger homes with multiple bathrooms which need hot water. They can also be more efficient and easier to install if you have a conventional boiler already. The most sensible thing is to think carefully about which type is most suitable for you and your property before buying.

Michael Cornish