I have recently installed a sealed central heating system with a Worcester Combi boiler and although the majority of the system and boiler runs very quietly there is one pipe that gives a constant water rushing sound. The pitch of this sound can be adjusted with the TRV on the radiators near to the pipe, but I cannot stop it. In addition when the heating is up to temperature some of the rad valves give off a hammering noise until you adjust the valve.
Can anyone help please??