Hi, I have an existing 6mm TandE cable, at the consumer unit the sheath is white, at the other end, in the loft, the sheath is grey. The cable is dead. The cable is obviously joined somewhere. My question is, if the cable tests ok ie insulation resistance, continuity etc would you guys be happy to connect it to an 8.5kw shower or due to the hidden jb would you rather not? Many thanks.