"Phil K" wrote in message
...
"Doctor Drivel" wrote in
:


Have a length of plastic pipe on the flow & return at the boiler to
reduce noises running through the copper pipes.

I wondered about that. Has anyone else here found that to make a
significant improvement? It would be good if someone made a special
vibration-dampening pipe for this purpose.

The vibration-dampening pipe is called plastic pipe.