I have a glowworm micron 50ff which is very noisy which I can only liken to it having indigestion in that it sounds like it has trapped air which is bubbling intermittently inside the unit. It has only stared this in the past couple of months. It is 4 years old.
Many thanks for the advice - I will give your suggestion a go.......
Paul
August 2007
sounds like your boiler is kettleing which is what happens when your heat exchanger is scaled up and the boiler gets hot.
it's caused by condensate water dripping on to a hot heat exchanger
you can buy a chemical for this that you add to the system and just leave it in and it cures it.
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