We now have a shiny new electric shower and only need the stored water for one kitchen tap and one tap in the bathroom. I'm aware that the boiler is still heating the whole tank, so what's the best way to heat, say, half a tank? I'm getting an immersion heater, so do they make them so that they don't heat all the water? I'd rather use the gas boiler if possible though. My cylinder thermostat is about two thirds down - would it help if I moved it up so that it cuts out earlier or would this create problems?
