Evenin' All,
A first for me today. Never before seen. I was removing an old brown three terminal choc block that had been recessed into a very old lime mortar brick wall inside a house. The cable ran to an outside high level light. When I removed the choc block it just crumbled like seaside rock. I couldn't believe just how brittle it was. It was only supplying a single outside light mounted on a wooden back mounting block. No overheating evident.
P.S. Add. The outside wooden mounting block for the light was screwed to the outside wall. The installer was a boat builder so the wood is probably marine grade "teak" or similar. Could the wood have given off fumes that worked their way through the hole in the wall to the chock block insulation and attacked it?
The cause? Chemical reactions?
Ideas please.
Z.
