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Many people assume that only one type of boiler works for everyone. However, boilers are classified into different categories. The most well-known types of boilers in the UK are condensing and combi. In fact, they are popular for their advanced features.
However, both condensing and combi boilers are essentially the same. Like a system or regular boiler, combi is also a type of condensing boiler. In the UK, all non-condensing boilers have been banned by legislation since 2005. All modern boilers incorporate condensing technology. Thus, you won’t need to choose between a combi and a condensing boiler. If you are going to choose your next boiler. You’ll get both!
In this blog, we will share everything you need to know about combi vs condensing boilers.
Combi Boilers Vs. Condensing Boilers
Combi boilers are a type of condensing boiler. There is no comparison between combi boilers and condensing boilers. Because combi boilers comprise condensing technology. They are thus classified as condensing boilers.
Which One is Best- Combi or Condensing Boilers
Condensing boilers, including combi, are ultra eco-efficient boilers. They are made to use less energy during the heating cycle.
Thus, combi boilers are not better than condensing boilers. They are a type of condensing boilers, like regular or system boilers. Read further to get deep insight.
Understanding Condensing Boiler
A condensing boiler captures the heat from waste gases to warm up the water that returns to the boiler. This means it uses less energy to reheat water that cycles through your central heating system.
Here’s How It Works?
- A condenser boiler uses heat from burning fuel to warm your home’s systems. Hot water from a condensing boiler moves through your central heating system pipes.
- Once the cooling process is done. A heat exchanger warms the water before being pumped back into the boiler.
- The exhaust fumes are the power used to heat the heat exchanger. With less fuel needed, the hob works better, but how does that work?
- When the fuel is burned, the waste gas is extremely fast-cooled, and the water is heated. Rest assured that this heat will not be wasted. When waste gas condenses, it releases heat energy. This heat energy powers your central heating through your condensing combi boiler.
- Along with letting the cooling waste gases out into the air through the flue pipe, the water vapour from the flue gases is also collected and turned into a liquid. The waste water leaves the system using the boiler’s condenser pipe.
Hence, condensation is an innovation in boiler technology. That’s why it gained popularity.
As condensing boiler uses much less energy, it is an effective heating solution. It will lower your bills and reduce your carbon footprint.
How Much is The Cost of a Condensing Boiler?
The price of a condensing boiler depends on the complexity and quality of the model. However, average prices range from £500 on the budget end of the spectrum to almost £2,000 for top-of-the-range models from industry-leading manufacturers. These prices don’t include the cost of labour for boiler installation, which can range from £250 to £1,000. It also depends on where you are in the country. For example, London boiler installation prices will be higher than Newcastle’s installation pricing.
Which is The Best Condensing Boiler?
It depends on your needs. Some names, like Worcester Bosch, Viessmann, and Vaillant, are well known for being reliable, efficient, and having a diverse range of models.
What Is A Combi Boiler?
Combi boilers work by receiving signals from the home’s central thermostat. A signal is sent to the boiler, which starts when the temperature drops below a certain level. After that, heat is pumped through the central heating system again until the thermostat’s set point is reached.
The ‘combi’ part comes from when the hot water tap is turned on; a valve diverts the heating towards the water supply, providing hot water on demand without needing a storage tank.
Here’s How it Works
Regular boilers get cold water from a tank, often stored in the loft. The boiler’s heat then warms the water, which is stored in a hot water cylinder until needed.
However, a combi boiler gets cold water directly from the mains. Thus, they provide hot water instantly without the need to store it in a cylinder.
This means you can get hot water on demand, and it won’t run out like it does with other boilers. It also allows you to have additional space in your home without needing additional cylinders.
How Much is The Cost of A Combi Boiler?
Combi boilers cost similar to their condensing counterparts, and installation/labour will also cost similarly. The most inexpensive combi boilers may cost under £500. However, their power output will be significantly lower than that of more expensive models. That means they’re less likely to be suitable for larger homes or those with more significant heating/hot water requirements.
The Pros & Cons of Condensing, Combi Boiler
Pros | Cons |
Reduce energy bills: A condensing combi boiler uses less fuel because it releases heat from the waste gases. This means that it can lower energy bills. | Fixed hot water supply: A combi boiler might not be able to meet your hot water demand if your home has more than two bathrooms. |
Less Carbon Emissions: As they use less fuel. It means fewer carbon emissions. It makes condensing combi boilers an environmentally friendly option. | Trouble with old pipes: Sometimes, the existing pipes might not work with a new combi boiler. It would mean more work and higher installation costs. |
Hot water on demand: Combi boilers bring hot water straight from the mains to your faucets and showers whenever needed. | Not ideal for low mains pressure: Low pressure isn’t suitable for combi boilers. Because they work best with high water pressure. Thus, they are not the best option for properties with low pressure. |
Less space: Its compact design does not require a cold water tank or external hot water cylinder, freeing up space in your home. | |
Ease of installation: A combi boiler is relatively easy to install. Because it has fewer parts and a simple design. |
Regulations for Condensing and Combi Boilers
There are several essential regulations for condensing and combi boilers that you need to know about before purchasing/installing one. In short, there are principal regulations you need to be aware of, and they pertain to a condensing/combi boiler’s overall efficiency rating:
- Condensing boilers installed after 2005 (exact on-April 2005) must have the lowest SEDBUK (Seasonal Efficiency of Domestic Boilers in the UK) rating of B. Ratings are always preferable, however.
Can You Still Install A Non-Condensing Boiler?
As mentioned above, non-condensing boilers are banned from sale in the UK. New Boiler Plus legislation stipulates that only condensing boilers can be installed.
Non-condensing boilers were the most popular type of boiler before condensing technology came along. Boilers that do not condense send waste-burning gases outside, releasing carbon dioxide and losing money and heat. Instead, condensing boilers reuse the heat from the burning process.
If your boiler was installed before 2005, you may still have a type that doesn’t condense water. You should switch to a condensing combi boiler instead of these types. Because they are inefficient. The difference in how well it works will be clear, and the lower running costs are a bonus.
Moreover, the UK government has launched the Energy Company Obligation ( ECO4) Scheme to make it a top home heating solution. This scheme helps low-income households access this condensed technology. People with old, non condensing boilers can get a free condensing boiler for their home.
However, this scheme has specific eligibility criteria. So, make sure to check your eligibility here applyforgovernmentgrants.co.uk before applying.
Conclusion
After this in-depth analysis, we hope you are clear that there is no real difference except for the types of condensing boilers. Different types of condensing boilers exist, such as combi, system, and standard boilers. You should be ready to get a new boiler. Boilers that are condensing or hybrid are better than older, more traditional types. Both offer high-efficiency rates and can last long, provided they’re maintained correctly.
Condensing combi boilers are a good option for those with less space. They don’t require an extra water tank. So, they are the best heating solutions for UK homes.
Frequently Asked Questions
Yeah! The Combi boiler is part of a condensing boiler. All modern domestic boilers, including combi, systems, and regular boilers, use condensing technology to make them more energy efficient.
So when choosing the right boiler for your home, you don’t need to choose between a combi boiler and a conventional boiler as all combos are condensing.
Combi boilers work best in small to medium-sized homes. They provide instant hot water or heat.
And they don’t require extra water tanks or cylinders.
Although condensing boilers are very efficient, they also have some drawbacks. They cost more to buy and set up. The vapour pipes can freeze in cold weather and may need to be serviced more often.
Absolutely! Low-income households with non-condensing boilers ( installed before 2005) can get free condensing boilers under the ECO4 scheme.
