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Boilers 101: Different Types of Boilers

With the cold season approaching, you might be thinking about the best way to keep yourself and your home perfectly warm. Or, perhaps your current heating arrangement isn’t doing a good job anymore.

Either way, you need something to heat up your house, and one thing you must be hearing most about is a boiler. A boiler is a good heating system for your house, but which boiler is the best for you?

Keep reading to find out about the different types of boilers, how they work, and which one is the best for you.

How Do Boilers Work?

A boiler heating system basically works by circulating hot water or steam throughout the house to warm the space. Most new boilers use hot water, but some older versions use steam as well.

There’s a water tank that is heated to produce hot water or steam that flows through the pipes and radiator to heat up the house. The tank sits atop some kind of burner that uses fuel to burn and heat the water tank. Most commonly, this fuel is natural gas that is supplied to each house, but where this gas is not available, people use other fuel types as well, such as propane gas.

Types of Boilers

Fundamentally, all boilers work the same way as we’ve briefly described. However, that’s the extent of any similarities. If you’ve done any research on boilers yourself, you’d know that the market is full of all types of boilers, ranging in size, features, efficiency, and whatnot.

So, let’s take a look at the different types of boilers available.

Gas vs. Oil vs. Electric Boilers

This must be pretty self-explanatory from the name itself. Gas boilers use gas, oil-fired boilers use oil, and electric boilers use electricity. However, there’s more to them than that.

Gas-fired boilers use natural gas or propane to run. These are quite efficient, and most UK homes are fitted with this type of boilers. Oil-fired boilers are less common and are mostly found in areas where there’s a limited supply of natural gas. Depending on which type of oil is used, an oil-fired boiler can incur high operating costs as well as low maintenance and cleaning costs.

Electric boilers are the most energy-efficient of the three. They don’t burn or use any kind of fuel to heat the water. Instead, they use electricity. Besides being energy-efficient, they are also much safer as there isn’t any risk of a gas leak.

However, electric boilers can significantly drive up your energy costs as electricity is much more expensive than gas or LPG. You can read more about gas and electricity prices here.

Unvented hot water cylinder with the gas boiler
Sealed system boiler with hot water cylinder

Condensing vs. Non-Condensing

Another difference between types of boilers lies between the condensing and non-condensing boilers. Condensing boilers have different vent systems than non-condensing boilers.

They use waste heat to preheat cold water entering the boiler, and often in the process, produce concentrated water vapor. They use heat from the outside rather than inside the room. All these reasons are why condensing boilers are considered to be more energy-efficient than non-condensing boilers.

Non-condensing boilers usually run at higher temperatures as compared to condensing boilers and also waste a lot of heat in the process. However, condensing boilers also tend to have more complex controls with expensive installation and repair costs.

Sealed Combustion vs. Non-Sealed Combustion Boilers

Between these two, we always recommend going for sealed combustion boilers as they are not only more efficient but also much safer to use. Sealed combustion boilers only use the air outside to bring into the burner and then promptly direct all exhaust gases outside.

On the other hand, non-sealed combustion boilers draw in the heated air from inside to the burner as well and then send it out through the chimney. This results in the wastage of energy used to heat the house. Moreover, because of its closed-off design, sealed combustion boilers pose no risk of introducing combustible gases into your home, making it a much safer choice. Standard Efficiency vs. High-Efficiency Boilers

The most important thing you have to consider is whether your boiler is a standard efficiency or high-efficiency boiler. This can make a big difference in your energy costs and boiler operating costs. Standard efficiency boilers usually waste a lot of energy while converting that energy into usable heat for the house.

They burn more fuel to provide the same level of heating that is provided by a high-efficiency boiler. Because of this, high-efficiency boilers can help bring down your energy costs. However, they also tend to have a higher initial cost and require a slightly complicated installation. Other than that, since they use less fuel, high-efficiency boilers also tend to be more environmentally friendly.

Final Thoughts

A gas engineer can help you to determine which boiler is the best for you
Gas engineer signing the boiler paperwork

A good boiler can easily last you for a decade or two with proper maintenance and repair. Therefore, you should spend some time learning about the types of boilers and which one is suitable for you.

While you are purchasing a boiler do keep in mind some crucial factors, for instance, how big your house is, how many people there are, if you want to use hot water for other purposes besides heating, your budget, etc. Ultimately, all these factors will determine which boiler is the best for you.

If you’re not sure which boiler will work best for you, consult one of our experienced gas engineers. Our Gas Safety registered engineers will do a thorough inspection of your house and can help you determine which boiler will work best. Visit our website to book a session today.

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