Should My Boiler Be Well Ventilated?

Should My Boiler Be Well Ventilated?

Posted on June 11, 2021

If you have a condensing boiler then you probably don’t need to worry about boiler ventilation. And if you have had a boiler replaced since April 2005, then you will more than likely have a condensing boiler.

The reason why condensing boilers don’t need to be well-ventilated is because they have a balanced flue pipe – Which gives it all the ventilation it needs. Great news if you’ve got your condensing  boiler tucked away in a cupboard!

If your home has an older boiler which is non-condensing, you will need to be conscious about ventilation – Or better still, replace it with a new condensing boiler!

Why do some boilers need ventilation?

Gas boilers need oxygen to help them to burn gas and keep certain parts of the boiler from getting too hot.

Most modern boilers seal off the combustion chamber, where the gas is burned, from the room. This type of boiler gets the air it needs through a balanced flue pipe which removes waste gases as well as getting the air boiler needs. Hence, they don’t need to be ventilated.

Some older, non-condensing boilers are not room sealed and have an open flue. The open flue pipe takes away the waste gas, but it doesn’t bring in any oxygen, which means they do need to be well ventilated.

If you have a room-sealed, condensing boiler with a balanced flue, then you probably don’t need to worry about ventilation for your boiler. If you’re unsure what type of boiler you have and whether or not it needs ventilation, speak to your installer or a Gas Safe registered heating engineer.

A balanced flue pipe – What is it?

With newer, condensing boilers with balanced flue pipes, boiler ventilation isn’t something you need to worry about. All boilers installed since April 2005 will be condensing boilers with balanced flues.

Balanced flue pipes have two tubes:

  • One to take waste gas away from the boiler and into the atmosphere
  • One to let oxygen into the boiler.

The balanced flue pipe with these 2 tubes gives a condensing boiler all the ventilation it needs. Older boilers have a conventional flue pipe which only gets rid of the waste gas – They don’t allow oxygen back into the boiler. Hence why older boilers will need ventilation.

My boiler is in a cupboard – Does it need ventilation?

If your boiler isn’t an open-flue boiler, and is room-sealed, then it’s absolutely fine for it to be fitted into a cupboard – You shouldn’t have any concerns about ventilation in this case.

However, it is worth considering whether a heating engineer will have easy access to a boiler in a cupboard when it comes to services, maintenance and repairs.

Here are a few standard regulations to consider when fitting a boiler into a cupboard:

  • The door of the cupboard must be able to open
  • There should be a 30cm gap between the top of the cupboard and the top of the boiler
  • There should be a 10cm gap between the boiler and the bottom of the cupboard
  • There should usually be at least 60cm between the front of the boiler cupboard and another wall to allow for services, maintenance, repairs and replacement
  • In order to meet some of these regulations, some cupboards may not have a top or bottom
  • If you are considering hiding your boiler in a cupboard, always make sure you check the manufacturer’s instructions and recommendations

All boilers manufacturer’s instructions should be followed as they can allow for departures from the standard gas regulations and building regulations. If you are in any doubt then take advice from them and a gas safe registered business.

Do I need a condensing boiler?

A room-sealed, condensing boiler can be a real benefit to your home for a number of reasons.

  • You don’t need to worry about ventilation, as a condensing boiler with a balanced flue pipe gets all the ventilation it needs. A balanced flue can only be fitted to a condensing, room-sealed boiler
  • Because added ventilation around the boiler isn’t necessary, it’s harder for the heat around your radiators to escape – Keeping your home warmer for longer
  • The part of the boiler that burns the fuel is sealed off from your home, which is much safer.
  • This also means they give you added flexibility in where they can be situated, such as a bathroom, bedroom or garage (you can’t do this with older boilers that aren’t room-sealed)
  • They’re more efficient and reliable

Want a new boiler quote?

If you currently have an older boiler and are considering upgrading to a condensing boiler then contact us today to see how we can help. You can also head to our website for a free new boiler quote.