A combi boiler is a type of boiler that provides both hot water and central heating from the same unit. It is called a combi boiler because it is a combination of a water heater and a central heating boiler in a single compact unit. Combi boilers heat water directly from the mains when you turn on a tap, so you won’t need a hot water storage cylinder or a cold water storage tank in the roof space.

Here is how a combi boiler works:

  1. When you turn on a hot water tap, the boiler senses the demand for hot water and ignites the fuel.
  2. The fuel is burned in the boiler’s combustion chamber, which heats up the water in the primary heat exchanger.
  3. The hot water from the primary heat exchanger is then circulated through the radiators in your home to provide central heating.
  4. Any excess hot water from the primary heat exchanger is passed through the secondary heat exchanger, which heats up the cold water from the mains.
  5. The hot water from the secondary heat exchanger is then piped to your hot water taps.

Combi boilers are very efficient because they only heat the water that is needed. This is in contrast to older boiler types, such as system boilers and conventional boilers, which heat water that is stored in a cylinder. This wasted heat can account for up to 30% of the energy consumption of a boiler.

Combi boilers are also very compact and can be installed in a small space, such as a kitchen cupboard. This makes them ideal for small homes or apartments.

What is a combi boiler?

A combi boiler is a type of boiler that provides both hot water and central heating from the same unit. It is also known as a combination boiler or a compact condensing boiler. Combi boilers are becoming increasingly popular in the UK as they are very efficient and space-saving.

Combi boilers work by heating water directly from the mains when you turn on a hot water tap. This means that they do not need a hot water storage cylinder, which can save space and improve efficiency. The hot water from the mains is heated up in the boiler’s heat exchanger and then piped to your hot water taps.

When the boiler is not providing hot water, it can be used to heat your central heating system. The hot water from the heat exchanger is circulated through your radiators to provide warmth.

Combi boilers are very efficient because they only heat the water that is needed. This is in contrast to older boiler types, such as system boilers and conventional boilers, which heat water that is stored in a cylinder. This wasted heat can account for up to 30% of the energy consumption of a boiler.

Combi boilers are also very compact and can be installed in a small space, such as a kitchen cupboard. This makes them ideal for small homes or apartments.

Here are some of the advantages of combi boilers:

  • They are very efficient.
  • They are compact and take up very little space.
  • They are easy to install.
  • They are relatively quiet.
  • They are available in a variety of fuels, including gas, oil, LPG, and electricity.

Here are some of the disadvantages of combi boilers:

  • They can be more expensive to purchase than other types of boilers.
  • They may not be suitable for homes with high demand for hot water.
  • They can be more sensitive to fluctuations in water pressure.

Overall, combi boilers are a very efficient and convenient type of boiler that is ideal for small homes and apartments. However, they can be more expensive to purchase than other types of boilers and may not be suitable for homes with high demand for hot water.

Are combi boilers gas or electric?

Combi boilers can be gas or electric. Gas combi boilers are the most common type of combi boiler in the UK. They are powered by natural gas or LPG and are very efficient. Electric combi boilers are less common, but they are becoming more popular due to their environmental credentials. They are powered by electricity and are very clean-burning.

Gas combi boilers explained

A gas combi boiler is a type of boiler that provides both hot water and central heating from the same unit. It is also known as a combination boiler or a compact condensing boiler. Gas combi boilers are becoming increasingly popular in the UK as they are very efficient and space-saving.

Gas combi boilers work by heating water directly from the mains when you turn on a hot water tap. This means that they do not need a hot water storage cylinder, which can save space and improve efficiency. The hot water from the mains is heated up in the boiler’s heat exchanger and then piped to your hot water taps.

When the boiler is not providing hot water, it can be used to heat your central heating system. The hot water from the heat exchanger is circulated through your radiators to provide warmth.

Gas combi boilers are very efficient because they only heat the water that is needed. This is in contrast to older boiler types, such as system boilers and conventional boilers, which heat water that is stored in a cylinder. This wasted heat can account for up to 30% of the energy consumption of a boiler.

Gas combi boilers are also very compact and can be installed in a small space, such as a kitchen cupboard. This makes them ideal for small homes or apartments.

Electric combi boilers explained

An electric combi boiler is a type of boiler that provides both hot water and central heating from the same unit. It is also known as a combination boiler or a compact condensing boiler. Electric combi boilers are becoming increasingly popular in the UK due to their environmental credentials. They are powered by electricity and are very clean-burning.

Electric combi boilers work by heating water directly from the mains when you turn on a hot water tap. This means that they do not need a hot water storage cylinder, which can save space and improve efficiency. The hot water from the mains is heated up in the boiler’s heat exchanger and then piped to your hot water taps.

When the boiler is not providing hot water, it can be used to heat your central heating system. The hot water from the heat exchanger is circulated through your radiators to provide warmth.

Electric combi boilers are very efficient because they only heat the water that is needed. This is in contrast to older boiler types, such as system boilers and conventional boilers, which heat water that is stored in a cylinder. This wasted heat can account for up to 30% of the energy consumption of a boiler.

Electric combi boilers are also very compact and can be installed in a small space, such as a kitchen cupboard. This makes them ideal for small homes or apartments.

Benefits of combi boilers

Combi boilers are a type of boiler that provides both hot water and central heating from the same unit. They are becoming increasingly popular in the UK due to their many benefits, including:

  • Efficiency: Combi boilers are very efficient, typically achieving an efficiency rating of 90% or higher. This means that they waste less energy, which can save you money on your energy bills.
  • Compact size: Combi boilers are very compact, taking up much less space than traditional boilers that require a hot water cylinder. This makes them ideal for small homes and apartments.
  • Instant hot water: Combi boilers heat water directly from the mains, so you don’t have to wait for hot water to come from a storage cylinder. This is ideal for homes with multiple hot water outlets, such as kitchens and bathrooms.
  • Easy to install: Combi boilers are relatively easy to install, making them a good option for homeowners who don’t want to spend a lot of money on installation.
  • Low maintenance: Combi boilers require very little maintenance, making them a low-cost option to own and operate.
  • Environmentally friendly: Combi boilers are more environmentally friendly than traditional boilers, as they produce less emissions.

Overall, combi boilers offer a number of benefits that make them a good choice for many homeowners. If you are looking for an efficient, compact, and easy-to-use boiler, a combi boiler may be the right choice for you.

What temperature should a combi boiler be set at?

The ideal temperature for a combi boiler depends on a number of factors, including the size of your home, the number of people in your household, and the climate in your area. However, as a general rule of thumb, the heating flow temperature for a combi boiler should be set between 60 and 70 degrees Celsius. This will ensure that your home is warm and comfortable without wasting energy.

If you have a small home or live in a mild climate, you may be able to set your boiler to a lower temperature. However, if you have a large home or live in a cold climate, you may need to set your boiler to a higher temperature.

It is also important to consider the hot water temperature when setting your combi boiler. The hot water temperature should be set between 50 and 60 degrees Celsius. This will ensure that your hot water is hot enough to bathe and shower without scalding you.

If you are not sure what temperature to set your combi boiler at, you can always consult with a qualified heating engineer. They will be able to assess your individual needs and recommend the best temperature setting for your home.

How long do combi boilers last?

Combi boilers typically last for 10 to 15 years with proper maintenance. However, there are a number of factors that can affect the lifespan of a combi boiler, including:

  • The quality of the boiler. Higher quality combi boilers tend to last longer than lower quality boilers.
  • The frequency of servicing. Combi boilers that are serviced regularly tend to last longer than those that are not serviced regularly.
  • The water quality. If the water in your area is hard, it can damage the boiler’s components and shorten its lifespan.
  • The frequency of use. Combi boilers that are used more frequently tend to wear out faster than those that are used less frequently.
  • The environment. Combi boilers that are exposed to extreme temperatures or humidity may not last as long as those that are not.

If you want your combi boiler to last as long as possible, it is important to have it serviced regularly by a qualified heating engineer. You should also check the water quality in your area and take steps to protect your boiler from extreme temperatures or humidity.

What size combi boiler do I need?

The size of the combi boiler you need for commercial use will depend on a number of factors, including:

  • The size of the premises. The larger the premises, the larger the boiler you will need.
  • The number of people who will be using the premises. The more people who will be using the premises, the larger the boiler you will need.
  • The type of commercial activity that will be taking place in the premises. Some commercial activities, such as laundries and restaurants, require more hot water than others.
  • The climate in the area. If you are in a cold climate, you will need a larger boiler than if you are in a warm climate.

As a general rule of thumb, you should size your combi boiler to provide enough hot water for 3 times the number of people who will be using the premises. For example, if you have a premises that will be used by 10 people, you should size your combi boiler to provide enough hot water for 30 people.

If you are not sure what size combi boiler you need, you can always consult with a qualified heating engineer. They will be able to assess your individual needs and recommend the best size boiler for your commercial premises.

Should I get a combi boiler or heat only boiler?

Whether you should get a combi boiler or a heat only boiler depends on your individual needs and circumstances. Here is a comparison of the two types of boilers to help you decide:

Combi boiler

  • Pros:
    • Very efficient
    • Compact and takes up very little space
    • Easy to install
    • Relatively quiet
    • Can be used for both hot water and central heating
  • Cons:
    • Can be more expensive than heat only boilers
    • May not be suitable for homes with high demand for hot water
    • Can be more sensitive to fluctuations in water pressure

Heat only boiler

  • Pros:
    • Less expensive than combi boilers
    • More suitable for homes with high demand for hot water
    • Less sensitive to fluctuations in water pressure
  • Cons:
    • Less efficient than combi boilers
    • Takes up more space
    • More difficult to install
    • Not as quiet as combi boilers
    • Cannot provide hot water and central heating at the same time

If you have a small home or apartment and do not have a high demand for hot water, a combi boiler may be a good option for you. Combi boilers are very efficient and compact, and they can provide both hot water and central heating from the same unit. This can save you money on your energy bills and space in your home.

If you have a large home or have a high demand for hot water, a heat only boiler may be a better option for you. Heat only boilers are more affordable than combi boilers and can provide more hot water. However, they cannot provide hot water and central heating at the same time, so you will need to have a separate hot water cylinder.

Ultimately, the best type of boiler for you will depend on your individual needs and circumstances. If you are not sure which type of boiler is right for you, it is always best to consult with a qualified heating engineer. They will be able to assess your individual needs and recommend the best type of boiler for your home.