I've been on this forum before with the problem of sludge. My living room rad doesn't heat up properly we've narrowed it down to sludge in the system, having re decorated recently we managed to remove 5 of the 13 downstairs rads (all 5 being doubles). The system is gravity fed and is about 20 years old. We've used sentinel X400 and it improved things slightly but its still not brilliant. I've been looking at using Fernox DS 40 as its meant to be more powerful, I'm not interested in power-flushing, mainly due to the fact i have flushed the majority of the rads already, and it seems like money for old rope.
Also would DS40 alleviate the problem of boiler kettling?
Cheers.
Also would DS40 alleviate the problem of boiler kettling?
Cheers.