The majority of boilers work by burning gas in order to heat water. This circulates in turn around the hot water cylinder and central heating system, or, in the case of a combi boiler, sends the water directly to the taps.

During their function, excess heat is created along with some other unwanted by-products which have to be safely vented away by the flue. Therefore, a flue is an essential component of any central heating system, which raises the question, can you flue a boiler through a chimney? Here, we answer this question and look at why the flue is so important.

What Is Meant By A Boiler Flue?

A boiler flue in all essence is the chimney of the boiler. However, rather that soot and smoke being channelled outside the home, primarily it is water vapour and carbon dioxide that is emitted. Small amounts of other hazardous substances are also produced by boilers, such as nitrous oxide and carbon monoxide.

These, too, must be vented to the exterior of the property via a flue. When the flue is placed correctly in line with the regulations, all the unwanted gases will be sent safely outdoors, away from the property’s interior and safely away from the public and the ground.

How Do Flues Work?

Flues are pieces of pipework or ducting which move hot aim and gases from the boiler’s combustion chamber to the outside. With a condensing boiler, a flue is, essentially, a part of its heating system, since it’s the heat produced by the burning gases that begins to warm the water that is returning from the heating system.

As the incoming water gets hotter, the hot gases lose some heat energy to the water, and this is how water vapour inside the flue gases can return to liquid water, resulting in their name “condensing” boiler.

In the case of most modern boilers, the flue will horizontally pass through the wall on which the boiler has been mounted. A boiler located outdoors has a different kind of flue arrangement to keep it in alignment with regulations. There are also some boilers that have a flue which passes vertically through the roof. If a boiler is placed elsewhere than on one of the property’s external walls, a vertical flue will also probably be required.

Vertical flues require a cover on the top in order to prevent snow, leaves, rain, and other possible blockage causes from getting in whilst also ensuring the gases are able to safely escape. A horizontal flue won’t usually require a cover, but if it is near a tree, fitting a guard about it will prevent the leaves from falling inside. Blocked flues are dangerous since the gases have nowhere to escape to and end up back inside the property.

What Regulations Are There About Flues?

Since the gases that come out of flues are potentially hot and toxic, there are important regulations about where and how they are sited. Those rules prevent the dangerous gases from getting into either your own property or that of your neighbours, and to protect from hot gases which could scald somebody.

In order to ensure the minimum safety standard is met, the flue has to be located at a certain distance from air bricks, windows, corners, the ground, and openings. A more powerful boiler will often require a bigger clearance between objects and the flue.

Fortunately, as a homeowner, you won’t be required to know those safety measure specifics since your Gas Safe boiler and flue installer will understand them and apply them appropriately when installing your new boiler.

Is A Chimney A Suitable Flue?

The terms “chimney” and “flue” are often used interchangeably, so surely a chimney would be suitable for use as a boiler flue? The answer to this question is yes, but there are caveats to this. It’s important to have the right type of boiler to be compatible with a chimney as a flue, and it’s also essential to use the services of an experienced and fully qualified team of Gas Safe installers who have the necessary skills and expertise to do the job properly.

Here at Rowlen, we are specialists in the field of all aspects of boilers and heating systems, including creating boiler flues from existing chimneys. If you want to use your chimney as your boiler flue, don’t hesitate to contact our professional team now.

We can work with you to come up with the most suitable and safe design in line with the current safety regulations so that you can be confident that your boiler will function perfectly while keeping you and your family safe from hazardous gases that can be produced when your boiler is in operation. Call our team now and find out more about how we can help.