slug build up in pipes

BigMak

I've been working on my boiler lines, and I've notice that there is a lot of rust and slug in the lines. I have a very old boiler (steam conv to hot water), and expect some build up. its gotten to the point of black slimy slug is coating all the lines. I imagine there is a couple of inches of slug in the bottom of he boiler. I want to try and flush the system. given the age of the boiler, I don't want to do damage to it with something to harsh.

Suggestions?

Jamie Hall

Pure water. Flush, rinse and repeat.

But... that black sludge is most likely made up of a lot of magnetite and other iron compounds. Which had to come from somewhere... like the insides of the pipes and the boiler. You may be very close to a leak... or leaks...