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Boiler Advice

Changing to a combi boiler and is it a good idea to convert?

Changing to a combi boiler and is it a good idea to convert?

You might be considering switching from a boiler with an immersion heater, a hot water tank or a conventional boiler. What are the costs and is it possible?

This guide will answer most of the questions you have about changing from your existing heating system to a combination boiler. It also addresses potential limitations of changing to a combi boiler, when it is not a good idea, and how much a new combi boiler costs.

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Should you change to a combi boiler from a conventional boiler?

First, why switch to a new combi boiler?

People typically switch from an old traditional heating system to a combi boiler or system boiler heating system because of three factors:

  • Modern combi boilers are much more energy efficient and the A-rated models can achieve 94% energy efficiency.
  • Combi boilers are space-saving because they don’t need separate tanks like hot water cylinders
  • These are usually much simpler and less expensive to maintain and repair.

A combi boiler which is short for combination boiler is a boiler that provides both hot water as well as central heating in a single compact unit.

Combi boilers provide hot water almost instantly by turning on your central heating or using your hot water tap.

This unique feature is not available in boilers that use a hot-water tank which can run out if used too much. In such cases, you would need to wait for the water temperature to rise before you could use it.

When you turn on your tap, cold water passes through the boiler and the heat exchanger heats the water and transfers heat from the hot burning gases to the fresh cold water.

Combi boilers offer more flexibility than conventional boilers. You don’t have to place the boiler too close to a large storage tank.

They are therefore preferred by people with limited space in their living areas

How much does it cost to convert to a combi boiler?

Combi Boiler

Like most things, conversion costs from a system or conventional boiler depend on many factors.

Depending on the complexity of your installation, a change from a traditional boiler with a tank to a combi boiler installation costs anywhere from £2,200 to £4,000. However, if you have a back boiler and need a full replacement, expect costs over £4,000.

It is a good idea to get several boiler quotes before you make a decision on changing to a combi boiler.

The following factors can impact final new combi boiler costs:

  • Which type you are changing to a combi boiler from
  • Make or boiler brand
  • The boiler comes with a warranty.
  • If you need the boiler moved to a different location on your property.
  • The boiler’s location and are things like scaffolding necessary which could increase the cost.
  • Anything extra you may want such as radiators, pipework, power flushes or thermostats

Benefits of switching to a new combi boiler

A combi boiler can be used in most UK homes, making them the most widely-used domestic boiler.

However, they are not always the best especially if you have a larger home and require a back boiler replacement. Here are some things you should keep in mind as you consider your options.

If you don’t have high hot water demand or heating requirements, a combi boiler may be a good choice. Here’s why:

Efficiency of the Combi Boiler

According to boiler ERP efficiency guidance, modern gas combi boilers are very energy-efficient. Modern combi boilers are actually A-rated which means that they run at approximately 90% efficiency.

This means that for every £1 spent, only 10 pence are lost. That is a huge improvement on old non-condensing systems like back boilers that run at only 70% efficiency. Similar can be said for boilers over 10 years old that have not been serviced or maintained.

The efficiency difference does not only mean that the best combi boilers are more efficient for the environment, as they emit less greenhouse gasses like carbon dioxide. However, it also means that they use less fuel and will save you money on your energy bills.

Compact combi boilers can fit in kitchen cupboards

A combi boiler is the best choice for those with small spaces.

Some more compact combi boilers can even be described as kitchen cupboard fit boilers.

Conventional boilers are generaly take u much more space and require hot water stored in a a hot water cylinder to be able to give you it when required and as you can imagine, this takes up considerable space.

Combination boilers are also less expensive than traditional boilers, and they work well in smaller and larger properties.

They are also easier to install, service and repair. This can impact installation costs and other costs.

Which size boiler is best for you? A combi boiler is the best choice for you. It all depends on how many radiators are in your home.

If you’re looking for the right type of boiler to fit your home, read our expert boiler installation page for more information.

Less chance of breakdowns in winter

Many argue that combi boilers are more reliable because they don’t have as many moving parts. They also have longer life spans and are therefore easier to look after.

Our guide will help you to understand the various types of boilers.

Who is a Combi Boiler not suited for?

Combi Boiler

Combi boilers are the most popular type of domestic boiler in Britain and are therefore suitable for all properties.

A standard combi boiler will not work in larger homes, which are usually small to medium-sized.

Homes with low water pressure may struggle due to the fact that they rely on the water pressure for the mains supply. If this is low then the combi boiler will not work as well as another type.

A combi boiler might not be able maintain hot water for multiple bathrooms at the same time if they are located in different rooms.

A combi boiler might not be recommended for properties that are very old or have low pressure from the mains.

What is involved in converting to a combi boiler?

A conversion, which is essentially a replacement of a combi boiler, can be more difficult than a regular one. Converting from an older system to a new combi boiler installation takes more time, materials, and labor. This can impact the final cost.

This job is extremely difficult and illegal for the novice.

It is therefore crucial to have your boiler installed by a licensed Gas Safe engineer.

The following are the things a Gas safe engineer does when he/she swaps from an old boiler/system to a combi:

  1. Clean the central heating system.
  2. Removal of the existing conventional boiler and storage tank.
  3. Remove associated controls
  4. To determine if there are any problems with the existing pipework, inspect it.
  5. New combi boiler installation including any extras or pipework
  6. Magnetic filters and limescale reducers or silencers after a power flush or chemical flush
  7. Smart thermostats can be installed to help reduce energy waste.
  8. To ensure that the combi boiler is running properly, it will be tested. The gas engineer can also give tips for best use and maintenance of your combi boiler.

Combi boiler conversion conclusion

A combi boiler conversion is a big job, but it may be one that saves money in the longer term. Changing to a combi boiler replacement from a conventional boiler is arguably one of the best investments you can make in terms of keeping your gas bills lower, but only if your home is suitable.

Speak to a Gas Safe registered engineer if in any doubt or get a new combi boiler quote online now with our recommended boiler installation company which specialises in the replacement of your existing boiler to a combi.

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