What does the colour of your boiler flame mean?

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The colour of the flame is indicative of the state of your boiler, so let’s have a look at what the different colours mean and the action that should be taken.

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A blue flame

A healthy boiler will have a blue flame, which means that it is getting enough air supply for it to burn or combust at the right temperature. Think back to your school science lessons and the triangle of heat, fuel and air that a fire needs to burn. The blue flame is letting you know that your boiler is receiving the right amounts of these three elements.

Think of your boiler flame as you would a Bunsen burner flame from your science class experiments. Cut off the air or the fuel and the flame will go out; have the right amount and you will see a strong, blue flame.

Red and yellow flames

If you see a red or yellow flame, this is the time to call out a heating engineer. A red or yellow flame means that your boiler is not getting enough oxygen, which can lead to a build-up of soot and lower the temperature of the flame.

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The consequences are that more soot is produced, which will turn the flame a yellow colour, and you are at greater risk of carbon monoxide poisoning, which is produced when the flame burns this colour. Red and yellow flames are a warning sign that your boiler is in ill-health and you may need the services of a boiler installation Gloucester company such as hprservicesltd.com/gloucester-boilers/boiler-installation-gloucester.

What to do if your flame is not blue

If your blue flame is burning with sparks of red or yellow or the pilot light is going out, you will need a professional to look at your boiler. You should also check for any eye irritations, soot build-up or strange smells. The exceptions to this rule are gas fires and gas log fires, which are designed to replicate the look of a cosy home fire.

A boiler that does not combust properly and burn at the right heat not only costs more in fuel but also increases the carbon monoxide risk. Check your flame and test your carbon monoxide alarm.

Finally, make sure you have your boiler serviced regularly.