Immersion Heater or Water heater

[it0000]

I do not live in the UK so not always familiar with the right term. My mother has a flat in London that needs a new immersion heater to heat hot water for bathroom and kitchen.. She currently has an electric one that is very old and needs replacing. I went to B&Q, Homebase sites to look for a new one but all I find are the parts, not the new tank. Am I looking under the wrong name (I tried water heater).
Also any recommendations for someone that will sell and install.

 

[bobbychocolate]

Try searching water cylinder instead of water heater.