Noisy Potterton Combi Boiler

[moggie 939]

My new Potterton HE Combi Boiler works perfectly well, but unlike our neighbours ity seems noisy on start up!

Each time the boiler fies up there is a very loud 'woosh' accomanied by a bang as it kicks in. This of course happens not just on the first fire up but evertime th T.Stat clicks on.

No problems with heating or hot water - just noisy. Engineer says they are noisy, but it is only mine. It is as if it is building up gas and suddenly exploding! It has been checked 3 times for safety and all ok.

Any ideas?

Thank you

[The Builder]

I must admit that I'd be concerned about anything quite that violent. It could be a precursor to eventual mechanical damage.
On the other hand, they are known for noise, as you know.

In your position, especially with a new boiler, I would speak to Potterton myself, for reassurance............

http://www.potterton.co.uk/28.htm

[Hymie]

I have a Potterton combi boiler which occasionally does exactly the same thing.

It is almost certainly due to the late ignition of the gas from the main burner. The ignition is only delayed by a second or so – but it is long enough for a build up of gas, that when ignited is like a mini explosion.

I believe that it is either due to the poor position of the pilot light (not igniting the main burner reliably); and/or the pressure switch not operating quickly enough – with the boiler airflow having reached full speed before the gas is fed to the main burner. The pilot light then does not ignite the fast flowing gas reliably.

[moggie 939]

Thanks The Builder and Hymie - I will contact Potterton