It could be a worn bearing in your pump. Try bleededing pump, flush system could be gunk build up. I had to get a new one and noise abolished, not bad for 12 years that old pump!
Hi everyone, wonder if anyone knows why my old baxi boiler make a series of bangs after shut down? There is then a short pause and then it reactivates and dumps some water in the surplus tank in the loft for five seconds. System is hot and working well otherwise. Boiler is over ten years oldbut...