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Advantages and Disadvantages of a Combi Boiler

Are combi boilers good? Here are some pros and cons.

viessmann vitodens 050-w combi

In this article, we will discuss the advantages and disadvantages of a combi boiler.

While a combi boiler is suitable for the vast majority of UK homes. There are some instances where it is not appropriate.

The question is more about the house that will be heated by the combi boiler. Whether it is appropriate for that home, or whether it would be better served by a boiler with a tank. As an example, consider a system boiler.

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What is a Combi Boiler?

Combination boilers are essentially high-efficiency water heaters and central heating systems that can heat and supply hot water to your home without the need for a separate water tank. They have a single appliance that performs these two domestic duties (hence the name “combi boiler”). Compared to other central heating systems, they are typically smaller and compact.

Who are Combi Boilers for?

Combi boilers are best suited for small homes, couples, or families because of their compact size and ability to heat water on demand. Although it is possible, gas and LPG models of combi boilers are more common today.

What Are The Advantages and Disadvantages Of A Combi Boiler?

Before diving deeper into the advantages and disadvantages of a combi boiler. Let’s start with how it works because this will ultimately determine whether or not it will work for you.

worcester 4000 combi boiler

The way a combi behaves determines whether or not it can meet the hot water needs of the home it serves.

Because a combi boiler cannot produce more water than what is supplied by the mains, a home with a higher hot water demand will put too much pressure on it.

A system boiler, on the other hand, can produce a large amount of water to multiple taps at the same time and store more than 100 litres of hot water in a tank.

How Does A Combi Boiler Work?

Combi boilers have two separate heat exchangers.

As part of one of these heat exchangers, a pipe runs through the radiators.

The hot water supply is connected to the other heat exchanger via a similar pipe.

When you turn on a hot faucet, your boiler will begin heating water for your radiators.

After a valve is opened, the water is directed through a network of pipes.

A combi boiler frequently struggles to heat both the water and the radiators.

As a result, the combi boiler will typically need to stop heating the water for your taps and radiators. Make sure not to use your hot tap for at least 10 minutes while your house warms up if you just got home and it’s cold.

Because of this, when you turn on the hot water tap, you might hear the boiler turn on or off.

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Advantages of a combi boiler

  • They consume very little energy; the majority of them have an efficiency rating of 90% or higher.
  • You may be able to save money on the installation of a combi boiler. This is because, unlike other boiler types, no tank is required. This means less pipe work and a shorter installation time.
  • Because of their compact size, combi boilers are excellent space savers. Some are designed to fit inside a kitchen cabinet.
  • Hot water is delivered using the same pressure as the mains. As a result, you can take a powerful hot shower without using a separate pump.
  • Water is heated as needed. As a result, running a bath or taking a shower does not necessitate waiting.
  • When necessary, water is heated. As a result, taking a bath or shower does not necessitate waiting for a water tank to heat up.

Disadvantages of a combi boiler

  • Water pressure frequently drops when more than one appliance requires hot water at the same time.
  • They are less cost-effective to operate in general. Especially if your home has more than one bathroom.
  • Combi boilers do not have a backup immersion heater. As a result, if your boiler breaks down, you won’t be able to heat your water.

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Can a combi boiler provide water to two taps at the same time?

They can, but not as well as a different type of boiler with a hot water tank. A combi boiler over 35kw will provide adequate water pressure to two taps, but it is not a good idea if this is a frequent occurrence or if you want to run two showers.

Should I buy a combi boiler?

If you live in a small to medium-sized home in the UK, a combi boiler should unquestionably be considered. Most of them are so quiet that you’d never know they’re there, and they’re designed to be neatly tucked away in kitchen cabinets.

However, unless your hot water needs have significantly decreased, we strongly advise you to consider a system boiler if you live in a larger house. If you want to get rid of your hot water tank to make room for a nice new cupboard, you could switch to a combi boiler!

Find out which combi boiler is the best for you

Comparing Boiler Quotes to Purchase A Combi Boiler

Because Compare Boiler Quotes works with a network of expert boiler installers who have been replacing and installing new boilers for many years, you can trust that all work done by our Gas Safe heating engineers is done safely and effectively.

When investing in a new energy-efficient boiler, you want to make the best decision and get the best price.

When you choose a new boiler from us, you will have a number of options and payment methods to choose from.

We always make sure you get the best deal with packages tailored to your needs, whether you decide to buy your new boiler outright or on boiler finance.

Please contact us if you would like more information on our boiler prices or to request a quote.

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