Loud boiler noise

[RichardS]

Alpha 240E combi boiler. When starts up (HW or CH) I get an amazing noise that sounds like a cross between a jet engine and a really bad trombone player. There is excessive vibration of the boiler itself and the pipes.

The longer the boiler remains fired up the more the noise subsides and then stops. I don't think it's the pump because that keeps running (quietly) after the boiler stuts off.

Any clues on what the problem is or, failing that, how I can make it play a decent tune

richard.

 

[Agile]

Is this noise associated with the flame burning?

What does the flame look like as it makes the noise compared with when its quiet?

Does it sound like a 1945 Meshermitt fighter going into a powered dive?

Who installed or last serviced the boiler?

Tony

 

[RichardS]

The noise builds up quite quickly a few seconds after the flame ignites and dies down almost instantly as the flame goes out. The flame is blue at all times.

I'll give a quailified 'yes' to the Meshersmitt sound - assuming the sound effect guys in the movies got it right. I wasn't around to hear the original

The last service was by a Corgi-Registered friend of a friend about 18 months ago.

richard.

 

[Agile]

I would say that the boiler main heat exchanger is badly scaled with limescale.

To make matters worse neither the installer nor the servicer set the CH power output to match the radiator output.

What I was hoping you would say is that as the rads warm up and the flame modulates down towards minimum the noise subsides.

You did not say what pressure you are operating it at. To reduce the problem until its fixed you might be able to increase the presssure towards 2 Bar with the rads hot.

Tony Glazier

 

[RichardS]

Sorry, misunderstood about the flame. The noise does subside as things warm up - if we put the CH on then it's only noisy the first time the boiler fires unless there is a long time between subsequent fire-ups.

System pressure is on the green part of the gauge marked as number 1 when cold.

Thanks for your help and advice Tony.

richard.

 

[amadpirate]

what is the solution to this?

 

[45yearsagasman]

what is the solution to this?

If you have a valid question then start a new post of your own to save confusion.This is 5 years old.