Been doing some work on the central heating system (moving/adding radiators), and have noticed that the system does not have an expansion vessel attached. It's a sealed system boiler, with a gravity fed hot storage tank (vented). My question is whether an expansion vessel should be fitted to such a system, and if so, where abouts it should be located? I did a test on the system by pressurising to 1 bar at cold, and checking what pressure it went up to at hot temperature - pressure went to near 2 bar.
cheers
cheers