We had a Mira Sport 8.5kw shower which has been fine since we moved in 5 months ago. Last week it just stopped getting hot, warmed up ever so slightly but barely tepid. Assumed it had been in since the house was built 13 years ago & it was just it's time to die, so got a new Triton (8.5kw again) and swapped it this morning. Got the new one in, switched it on and the new one does exactly the same thing! Powers up but doesn't get hot, barely warm. Any ideas? I'm stumped!