hello people, i fitted a wood burner with a back boiler last year,when the fire gets going well the boiler starts to make a banging noise.this noise is the water boiling and flowing out the top pipe towards the neutralizer(it sounds allfull.the pump is running and the radiator's are hot but my question is,is this loud banging noise ok for the boiler or is there a chance this might split the boiler.it lasts for approx 10 mins until the fire dies down abit. any help greatfully received steve