by DONFRAMAC »
Tue May 22, 2007 1:22 am
The 2 local firms, and one professional on this forum, said it would return because the old type of plastic used 10 years ago, breathes air in thro' the tube-wall molecular structure, despite being water-tight;-- then the air promotes growth of algae, a mucky mid-brown colour;-- I have seen it in the header in the loft-- looks like cumberland sausage;-- only one downstairs radiator was affected then, so I renewed it.
I also had 2 dripping isolator valves to renew at the same time, so they could have been air-suckers, and a pump-valve nut was dripping, and got nipped tight.
At the moment the brown stuff in the header has not formed sausages, but coats the walls to about 2 cms-- soft squishy stuff. I have a few weeping isolator valves to seal-- ptfe tape may do it.