Noisy Glow Worm Ultimate Boiler

[diyken]

I have a Glow Worm Ultimate boiler about 8 years old on an older system. About a year ago it started banging, I guess it has sludge in it. I put in a Fernox cleaner and left it about a week then drained, flushed and refilled. The banging reduced but has now returned. A building control friend of mine has said a plumber told him to pour half a cup of washing up liquid into the header tank. He did and apparently the noise stopped. Can anybody tell me if this is sound advice? How would a heating engineer normally deal with this if it isn't a good idea?
Thanks in advance.

 

[ChrisR]

Washing up liquid corrodes your system! Corrosion inhibitors like Sentinel x100 and Fernox MB-1 have wetting agents in them.

 

[Gas2Air]

Deary me washing up liquid? If that doesn't work why not try Ajax?

Seriously have your system checked by an engineer for pipe configurations, mainly cold feed and open vent config in conjunction with your pump, check inhibitor levels, test water, check f/e tank, check boiler.

A good engineer will suss any fault that causes the banging.

What kind of banging is it? Where is it noisest? Does it continue or stop for periods of time?

 

[kevplumb]

bung it in a new boiler aint that expensive

 

[diyken]

Thanks for all those useful comments. Point taken about washing up liquid!! Gas2Air asks about the noise. It is definitely in the boiler and seems to coincide with the burner being on for a while and the water getting hot. It goes away for short periods but returns when the burner re-ignites. I had it serviced about a year ago but the noise wasn't too prominent then. Interestingly, when I cleaned and flushed the water came out fairly clean.
Thanks again folks.

 

[kevplumb]

water came out clean cos the sludge has baked on the heat exchanger hence the noise

 

[diyken]

Thanks kevplumb. Can you recommend a good de-scaler?