Evening. I've been having bother with the thermostat on my hot water tank immersion so I changed it on Sunday. The original one, (Backer and not very old), was replaced when I put a new tank in last year, the electrics were all done by a registered electrician. Problem was it was tripping out because it was too hot. No problem, reset it and it was fine for weeks. Anyway, I got fed up with all the resetting malarkey and changed the stat. Lo and behold, it wasn't hot enough, so I turned up the stat last night only to find tepid water tonight when I got home. A penny has dropped here, has the stat been wired up in reverse...? Every time I turned the old one down, it seemed to be just as hot or hotter. Now, when I turn it up, it IS a good bit cooler. Is this possible before I tear what's left of my hair out...?