30 units of electricity = 30 kW , a lot of power! This amounts to approx 5 kW of power per hour for 6 hours. If the water is somehow bypassing the tank and not heating up, then the element has been glowing red hot like a heater's bar, and has probably burnt itself out by now. Unless you are handy with d.i.y.projects, you will have to get an electrician/plumber to check the installation for the sake of safety. Trying to save a call out fee could cost you dearly in destroyed property, and peoples' lives even.
30 mths ago