I live in a flat where there is no gas supply and subsequently I am limited to an electric boiler. The problem I have is that the tank was fitted with a pump quite a few years ago but the hole for the pump into the tank was placed just in the way of one of the immersion heaters (bottom one). So, when the plumber came around to replace the immersion heaters he couldn't get the immersion heater to fit into the tank as there were pipes from the pump (I think) in the way. The person who had fitted the previous immersion heater had bent it in double to be able to get it to fit in.
The plumber that came over to do the work this time tried to bend the immersion heater also to be able to get it into the tank but was unable to do so (he informed me that the material used to make immersion heaters had changed by law to a tougher material which is why they were unable to bend the new one).
Anyway, they found a new shorter element - 7" - and was able to fit this into the tank successfully. This element is connected to the overnight Economy 7 heating system so the next and subsequent days I was expecting hot water in the morning. However, the water is at the best warm but mostly tepid. I checked the temperature it was set to and it was on the highest setting.
So my question is, is this element too small for my tank? The plumber had told me that even though this was a shorter element, it was just as powerful as the 11" one he was replacing. Can anyone advise me as to what I can do???