Hi, got a problem with the boiler making a banging noise when it finishes it cycle. BGas say it's the water heater on the way out but won't replace until it finally gives up the go. They suggested adding some silencer to the system to see if it helps. Have some Fernox Silencer but not sure which tank in the loft to put it in? One is clear with a lot of sediment at the bottom and the other is a bluey colour, which is which?
I have no idea if it needs one, the banging and clunking has only recently started happening when we had the cold spell. It does sound like the water is backing up. Take it the silencer would be a waste of money then, hpowever which tank is which in the loft?
From your point of view, the easiest way to tell which tank is which is to run the hot tap for a few minutes and then poke your head up the loft and see which one is filling. The one that is filling is for your hot water and the one that is not is for your heating.