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When people want to buy a new boiler or replace an old one with a more eco-efficient boiler, they may feel confused by all the choices. As for saving money and energy, you’ll mostly see condensing boilers. Therefore, many people are curious: what is a condensing boiler, how do they work and how are they different from other boilers?
This piece will discuss condensing boilers in great detail, covering how they work, the different kinds available, their pros and cons, and various other topics.
What is a Condensing Boiler?
During the first oil crisis in the 1970s, makers had to rethink their choices and find a way to make boilers that used less energy and cost less. They fixed the problem by running boilers at lower temperatures and changing the temperature of the water inside the boiler to match the temperature outside. There were many tests before the first condensing boiler came out in the 1980s.
How is a Condensing Boiler Efficient?
Non-condensing boilers are only 70–80% efficient, but condensing boilers have more modern technology that makes them up to 95% efficient. Their condensing technology uses a heat exchanger to collect water vapour from the exhaust fumes and warm up the water flowing through it. This reuses the latent heat of vaporisation that would have been lost. It is important to remember that for a condenser boiler to work at its best, the temperature should be around 55 °C.
Condensing boilers are very popular these days. Because they save energy and money, making them an excellent choice for lowering energy bills. The government of the UK also encourages homes to use boilers that use condensing technology.
How Does Condensing Boiler Work?
Up to 30–50% of the heat that non-condensing boilers make when they burn fuels like gas and oil is lost because the combustion gases escape into the flue. Getting rid of these waste fumes is essential because they can be dangerous. But these leftover fumes have heat in them that can warm your house. This is where gear for condensation comes in handy.
No matter what boiler it is, it has either one big heat exchanger or two smaller ones. That helps pull water vapour out of the waste gases and heat the water moving around. Thus, it will bring back the latent heat of evaporation that would have been lost. A non-condensing and condensing boiler takes in the same amount of heat. But because it can reuse the heat from the water returned to the boiler, it uses less fuel to heat the same space.
Advantages and Disadvantages of a Condensing Boiler
A condensing boiler can save money and reduce carbon footprints. However, with benefits, it also has some drawbacks that you might want to consider. Let’s discuss them in detail:
Pros | Cons |
Saves on your energy billsThe main benefit of a condensing boiler is that it works more efficiently, as was already said. Putting the heat from the waste gases back into the system can make your central heating system up to 90% more efficient. The economy can go up to 95% if you buy a combi boiler. | Expensive to maintainWhile condensing boilers have many operational benefits, they can be challenging for homes to maintain. Because they are so complicated, fixing them requires technical know-how, which means calling a Gas Safe licensed engineer. Their fees can be pretty high. A non-condensing boiler, on the other hand, is less efficient but costs less to fix. Don’t get a new condensing boiler unless your old non-condensing boiler has completely broken down. They are more expensive to keep and fix. |
Lowers carbon emissionsNot only does a non-condensing boiler lose gases and make your heating system less efficient. But it also puts CO2 into the air, which increases your carbon footprint. If you want to help the environment by lowering carbon emissions, buying a condensing boiler is always a good idea. | A complicated systemA condensing boiler is difficult to understand because it works so well and uses modern technology. When water condenses, it releases acidic water through a condensate pipe, which can rust or freeze in harsh weather. |
Safety and spaceA condensing boiler gets rid of waste and keeps you safe. This appliance is small, sleek and saves room. Because it doesn’t need an extra hot water storage tank. So it’s easy to fit in a kitchen drawer. Also, the system is completely shut and gets air from outside through a flue. This differs from non-condensing boilers, which bring air inside the room. This safety feature makes it less likely that something will get sucked into the boiler. | Prone to corrosionCondensing boiler parts are made of metal, which makes them prone to rusting. Because they release salty water, knowing if they can stop water from freezing is essential. Remember that the anti-freeze part can easily damage your boiler if you use it too much or too little. Because of this, you need to know how to use the anti-freeze function and check the pH level every year or two. |
How Do I Choose the Right Condensing Boiler?
This is the most common question that knocks out many homeowners. This is due to their lack of knowledge about condensing boilers and their benefits. But don’t worry; we will provide the essential factors to consider before purchasing a condensing boiler to simplify your decision-making process.
Here Are Some Key Points to Know
- You can choose from three main types of boilers for your home’s central heating system: combi, system, and regular/conventional boilers. Many people want to know if condensing and combi boilers are the same. The short answer is no, all combi boilers evaporate. Not all boilers are the same. There is a difference between them.
- When you decide to buy a boiler, you should consider what fuel it uses. Depending on where you live, you might be able to get oil, gas, or electricity. The type of fuel available where you live will determine how well and how much your boiler costs. Learning about the different fuel types is essential to choose the best one for your needs.
- Consider the pros and cons listed above and decide for yourself if you need a condensing boiler. Have you considered how difficult this method is to understand?
- Once you know the basics, compare the types’ features. How do I do that? Let’s have a look at these:
Wattage Output
The most important thing about a boiler, whether condensing or not, is its power number, which is given in KW. After you know how much you will be using it, pick the right power for your home. It’s easy to figure out: the output rate goes up as demand increases.
Warranty
It’s essential to think about a warranty. Anything can go wrong after you buy a boiler, from fitting problems to complications with how it works. Don’t forget to ask how long it lasts and what it covers.
Efficiency Rating
It is essential to examine the boiler’s efficiency number, which shows how well it can turn fuel into sound energy.
Customer Review
Customer reviews are critical to read because they tell you about other customers’ experiences and what to expect. Both the maker and the technician can be read about on Trustpilot.
Are All New Gas Boilers Condensing in the UK?
As of April 2005, all boilers built or changed must be gas-condensing and have an efficiency grade of 90% or higher. However, a Gas Safe Engineer may sometimes tell you to place a non-condensing boiler if the building is specific.
So, you should talk to a professional before changing or installing a new boiler. They will come to your home, look at it, tell you which boiler is best. And they will ensure you get a solution that works well and doesn’t cost too much.
Factors That Show You Have a Condensing Boiler
If you’re not sure if your boiler is condensing, you’re not the only one. Many people have trouble figuring out what kind of boiler they have. You will get a guidebook when you buy it. In case you can’t find or don’t understand the instructions, here are some things that might help:
- Start with easy things- Find out when your boiler was installed. If it was installed before 2005, it’s likely a non-condensing boiler that needs to be updated.
- Next, look outside your house for the flu. A boiler that doesn’t condense water is made of metal.
- Last, make sure that steam is coming out of the flue. A condensing boiler has plastic pipes and steam.
How To Choose Condensing Boiler According to Your Need and How Long Will It Last?
Picking the perfect boiler size for your home depends on the number of rooms or bathrooms. In this case, 24–30 kW would be the best size for a home with two to three bedrooms or bathrooms. If you have a bigger house with five to six bedrooms, 35 to 42 kW is the right size.
A boiler usually lasts between 10 and 15 years. But this can be stretched based on how often it is used and how well it is taken care of. You should get a cover when you buy a new boiler. For a complicated condensing boiler, this will cover the cost of fixes and upkeep in the future.
Cost of Top Branded Condensing Boilers
Brand | Boiler Type | Output | Cost |
Baxi | Combi Boiler | 24 kw | £633- £711 |
Baxi | System Boiler | 12 kw – 24 kw | £640- £1055 |
Idea | Combi Boiler | 24 kw | £880 |
Idea | System Boiler | 15 kw | £790- £925 |
Viessman | Combi Boiler | 30 kw- 35 kw | £1049- £1226 |
Viessman | System Boiler | 19 kw- 35 kw | £1015- £1298 |
Worcester Bosch | Combi Boiler | 28 kw- 30 kw | £859- £2000 |
Worcester Bosch | System Boiler | 12 kw- 35 kw | £825- £1405 |
Vaillant | Combi Boiler | 28 kw- 30 kw | £880- £1400 |
Vaillant | System Boiler | 25 kw- 30 kw | £1059- £1190 |
Installation Cost of a Condensing Boiler
The cost of installing a gas boiler will depend on the type of fuel used. A gas boiler is usually between £1500 and £2200, while an oil boiler can be as high as £2500 or more.
Conclusion
Lastly, a condensing boiler is the best choice to replace your boiler or buy a new one. We hope our comprehensive guide helps you understand what a condensing boiler is and how it works. It also provides information on how much it costs and its pros and cons. Knowing what a condensing boiler is and how it can improve your life can be especially helpful if you live in the UK, where cold weather can be rough.
Also, the government supports condensing technology to save energy and reduce carbon emissions. The UK government has developed a free boiler grant scheme for low-income households. Now everyone can enjoy advanced and comfortable heating. If you have an old non-condensing boiler installed before 2005 you can be eligible for this scheme. And you can get an A-rated condensing boiler for free.
