A condensing boiler is a heating device that is designed to provide efficient heat and hot water to non-domestic customers using gas or oil. It is a highly efficient device that uses a secondary heat exchanger to extract additional heat from the exhaust gases produced during combustion, resulting in minimal waste and maximum energy efficiency.

Businesses looking to invest in a new boiler will find that condensing boilers are an excellent choice. Compared to traditional boilers, condensing boilers are much more efficient and can significantly reduce energy bills over time. They also produce fewer emissions during operation, making them a more environmentally friendly option.

Additionally, condensing boilers are often more compact and easier to install than traditional boilers, which is especially important for businesses with limited space. With their high efficiency and easy installation, condensing boilers are becoming an increasingly popular choice for businesses of all sizes.

Overall, if you’re a business looking to invest in a new boiler, a condensing boiler is a highly efficient and cost-effective choice that can help you save money on your energy bills while also reducing your environmental impact.

What is a condensing boiler?

A condensing boiler runs on gas or oil and has been designed to help improve energy efficiency. This is done by converting water vapor condensation into heat; they’re able to recover some of the lost heat from waste gases. The only difference between a condensing boiler and a non-condensing boiler is the amount of useable heat it produces; plus the fact they can achieve over 90% energy efficiency.

How does a condensing boiler work?

Your boiler will use either gas or oil as fuel and it will begin to burn when lit. As it does so, it inputs the heat from the burner into a primary heat exchanger. The hot air travels through the heat exchanger and is kept here for as long as possible to bump up the temperature. It will then take this heat away to your radiators.

The heat also travels through a secondary condensing area, which is something other types of boilers don’t have. As it does so, the warm air condenses, causing droplets, or water vapor to occur -which are then collected and taken away to be disposed of via a drain. This is one of the main advantages of a condensing boiler as no other boiler will have this amount of efficiency.

Condensing boilers are designed to recover more heat before it is lost. In an older boiler, you could probably expect heat that leaves the flue to be over 200 degrees Celsius. With a newer, condensing boiler, it’s reduced significantly to around 55 degrees Celsius. Condensing boilers are great at recycling that heat to increase the temperature of the cool water that returns.

Condensing boilers vs non-condensing boilers

Condensing and non-condensing boilers both burn fuel, such as gas, but the main difference is that the energy efficiency of condensing boilers is up to 99% efficient while non-condensing boilers are only up to 78% efficient.

Condensing and non-condensing boilers both burn fuel, such as gas, but the main difference is that the energy efficiency of condensing boilers is up to 99% efficient while non-condensing boilers are only up to 78% efficient.

Advantages and disadvantages of a condensing boiler

Below we will be discussing the advantages and disadvantages of a condensing boiler.

What are the advantages of a condensing boiler?

Boiler efficiency – through recycling waste gases back into the system, a condensing boiler can have around 90% energy efficiency
Environmentally friendly – Produces fewer carbon emissions and condensing boilers do not let gases escape into the air.
Space Saving –  Often compact designs with various venting options

What are the disadvantages of a condensing boiler?

They are more complicated. These condensing boilers can shut down in extreme weather because their exterior pipe might freeze.
They are expensive to maintain.
They are corrosive.

Is a condensing boiler right for me?

Choosing the right boiler for your home can be an overwhelming decision. A new boiler can last around 10-15 years, so it’s important to find the right one to suit you and your lifestyle. Before purchasing a new boiler, it’s important to think of factors such as your heating and hot water requirements and any future home improvements you may be considering.

How much do condensing boilers cost?

Are you looking to buy a new boiler and wondering how much condensing boilers cost? The price (boiler costs only) is determined by a few things:
Size (kW output)

How long do condensing boilers last?

For an average household, boilers will last up to 10-15 years. Though it’s important to understand this timespan is conditional.

What size condensing boiler do I need?

The boiler size or power output is measured in kilowatts (kW).
The boiler size you require is largely determined by the number of radiators, bedrooms and bathrooms in your home.

What is a Condensing Boiler FAQs

What is the difference between a combi boiler and a condensing boiler?

A combi boiler combines the functions of heating and hot water supply in a single unit, eliminating the need for a separate water storage tank. While a condensing boiler refers to the technology used to maximize energy efficiency by recovering heat from flue gases, resulting in higher efficiency compared to non-condensing boilers.

How do I know if I have a condensing boiler?

To determine if you have a condensing boiler in a commercial setting, you can consider the following factors:

Look for the Flue: Check the flue system of your boiler. Condensing boilers typically have a visible flue pipe that expels the exhaust gases. The flue pipe of a condensing boiler is usually made of plastic or stainless steel, and it is designed to be cooler to the touch compared to non-condensing boilers.

Efficiency Rating: Condensing boilers are known for their high energy efficiency. Check the efficiency rating of your boiler. Condensing boilers typically have a high seasonal efficiency rating (SEDBUK rating) of 90% or above.

Age of the Boiler: Condensing boilers have gained popularity in recent years due to their efficiency benefits. If your commercial boiler was installed within the last decade, it is more likely to be a condensing boiler. However, it is essential to note that older boilers might have been replaced with newer condensing models.

Documentation and Manufacturer Specifications: Review the boiler documentation, manuals, or consult the manufacturer’s specifications to determine if your boiler is a condensing type. These documents often provide information about the specific model and its condensing capabilities.
Consult a Professional: If you are still uncertain about the type of boiler you have, it is recommended to consult a qualified heating engineer or commercial boiler technician. They can inspect the boiler, analyze its specifications, and provide a definitive answer based on their expertise.

Are all new boilers condensing boilers?

In the commercial sector, it is important to note that not all new boilers are condensing boilers, although the majority of them are. The energy efficiency regulations and building codes in many countries require the installation of condensing boilers in new constructions or boiler replacements. These regulations aim to promote energy efficiency and reduce carbon emissions. However, there may be exceptions and specific cases where non-condensing boilers are still installed, such as in certain industrial applications or specific building requirements. Therefore, it is advisable to consult local regulations and seek professional advice to determine the specific requirements and options for new boilers in your commercial setting.

Are condensing boiler fumes harmful?

Condensing boiler fumes are generally not harmful when the boiler is properly installed, maintained, and operating correctly. However, it is important to note that any combustion appliance, including condensing boilers, produces combustion byproducts that can be potentially harmful if there is a malfunction or improper ventilation.

Condensing boilers produce flue gases, primarily consisting of water vapor and small amounts of carbon dioxide (CO2) and other trace elements. The condensation process in these boilers helps to extract heat from the flue gases and maximize energy efficiency. The resulting condensate is acidic but is typically safely drained away.

To ensure safety, it is crucial to follow proper installation, maintenance, and ventilation guidelines for condensing boilers. This includes regular servicing by a qualified technician, adequate ventilation to allow proper air supply and exhaust, and ensuring that the flue system is correctly installed and functioning.

It is recommended to have carbon monoxide (CO) detectors installed in the vicinity of any gas appliance, including condensing boilers, as an additional safety measure. These detectors can provide an early warning in the rare event of a combustion issue or gas leak, which could lead to the production of harmful fumes, including carbon monoxide.

If there are concerns or suspicions about the safety of condensing boiler fumes, it is advisable to consult a professional heating engineer or technician who can assess the specific installation and provide guidance based on local regulations and safety standards.