triton electric shower

hi, im having a bit of trouble with my triton electric shower. its only just over a year old. when we first got it we used to have it the temperature on about number 5. but after a while it became too hot on this setting so we had to turn it down slightly, and gradually as time has gone on we've have to keep turning it dow, im guessing to a gradual drop in the water pressure. it got to the stage where its on the coldest setting and it was still red hot.the pressure has now got so low that im guessing the shower has some kind of cut-off which kicks in and cuts off the heat all together. i was wondering it this is caused by something slowly getting clogged and causing a reduced water pressure, and simply needs flushing through with something, or whether its a case of buying a new shower???? does anyone have any suggestions?

thanks

It might just need the shower head cleaning.
JonB

or the water input filter, if it has one.

im no expert, but if the head was blocked wouldnt that increase the pressure? i've no idea if it has a input filter, where would this be located?