How Does A Combi Boiler Work

Combi boilers are gas powered and can be very energy efficient when used correctly. And since there is no water storage tank, they are also ideal for smaller properties. For larger homes with high demands for heating and hot water, a system boiler might be better suited. If you're thinking about a combi boiler for your home, here is everything you need to know about how they work and how they can improve your home.

How does a combi boiler work?

A combi boiler is a gas powered appliance that heats water on demand. The central heating system is linked to a thermostat. When the internal temperature of the home drops below a set point, the central heating fires up and the combi boiler starts to pump heated water around the system. Once the desired temperature is reached, the boiler automatically switches off.

With the hot water system, the combi boiler turns on when the hot water taps are turned on. Rather than storing hot water in a cylinder and using this throughout the day, the hot water is heated instantly and on-demand. While this is a more energy intense way of heating water, it also means there is no waste. If you don't use any hot water in a day, then the system won't use any gas.

Combi boilers work by taking water directly from the mains. It passes the water through a heat exchanger, which is like a coiled pipe. The water passes through the pipe and the hot flue gasses pass over the pipes, heating the water inside. Cold water passes into the heat exchanger and hot water passes out.

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Is my home suitable for a combi boiler?

If you're considering a combi boiler for your home, there are a few things you need to consider. For starters, what is your current boiler system? If you already have a combi boiler installed and simply want to replace it, this will be a much easier task than changing your boiler system.

You should also consider the size of your property. A combi boiler will heat hot water on demand for your central heating and hot water taps. But if you have more than one bathroom in your home and need to power multiple showers, for example, you might be better with a systems boiler.

And finally, think about your water pressure. A combi boiler uses the mains water to produce your hot water. If you're not happy with you current water pressure, you might also be unhappy with hot water from a combi boiler. Using a system boiler with a tank in your attic might be more suited as this will increase your water pressure using gravity.

Advantages of combi boilers

There are many advantages to choosing a combi boiler for your home. Here are just some of the things to consider as you make your decision about modern combi boilers and if this is the right choice for your new boiler.

Lower energy bills

You could enjoy lower energy bills and heating bills thanks to the energy efficiency rating of many modern boilers. Since you only pay for what you use, you'll be rewarded for efficient use of your central heating system and could save money.

With smart controls, you could turn your heating system on and off while you're away from home, so you never need to worry about leaving the central heating on when you're not home and wasting energy. Saving energy is a big concern for many home owners as energy prices are increasing rapidly.

Hot water tap on demand

If your hot water runs out when you have a system that heats a hot water cylinder, then you'll have to wait for the cylinder to refill with hot water again. This can leave you feeling limited in the length of time you can use the shower, for example. Smaller cylinder may also struggle with some tasks, such as filling a bath. With a combi boiler, you'll enjoy instant hot water when you need it, so no more worrying about using all of the hot water.

Mains water pressure

A combi boiler takes water from your mains water supply, which means you can enjoy excellent water pressure. If you already have good water pressure, you don't need to worry about adding a hot water cylinder to your attic just to improve pressure. And since there are fewer components in a combi boiler, repairs by a Gas Safe registered installer will be much easier.

Straightforward installation

Replacing a combi boiler like for like is a lot simpler than switching to a new system. Getting a new boiler installed or replacing a regular boiler with a combi boiler can be more straightforward as there are fewer pipes involved.

If you're looking for a new combi boiler, ask your heating engineer about the options available to you. Replacing an old boiler with a modern boiler could help you to save money on bills and enjoy more reliable heat and hot water in your home.

Can boilers heat water and radiators at the same time?

Inside the combi boiler, the primary heat exchanger heats the radiator water while the secondary plate heat exchanger will heat the hot water. The combi boiler is capable of doing both at once, and some will be better at this than others. If you have high hot water demands, speak to your heating engineer about choosing the best combi boiler for your needs.