raden wrote in message ...
In message , Winged Cat
writes
Hi,
My friend's 18 year old boiler makes a groaning noise whenever it
cycles on. The noise stops once the boiler cycles off. I am wondering
whether noise reducer gel would be beneficial in this situation.

Sexy boiler the Elan

Could it be a washer vibrating?

Difficult to tell without a more precise explanation of the noise

At what point in the cycle does this filly make a noise ?

Well thank you for your help everyone. This afternoon I drained down
and refilled, adding 1 bottle of inhibitor and 1 bottle of noise
reducer and incredibly the noise has stopped completely. I cannot
believe the noise reducer can be directly responsible for the instant
disappearance of the noise. I thought it was supposed to work like a
descaler which I would have thought would take some time to have an
effect.

My theory at the moment is that the drain down has dislodged some
smeg/limescale that had accumulated in some crucial part of the system
(causing the noise) and it has either been drained away or displaced
to some area where it's not doing any harm. I can't really think of
any other rational explanation.