Triton aquatronic 4+ heat loss?

Hi all,
My shower went off with a bang and water with obvious signs of a burn up came out. The fuse had also popped. I replaced the fuse and it works fine again apart from the high heat setting button. It has three settings,cold,medium and hot. All the panel lights up ok but there is no difference between medium heat and hot. Is this repairable? I assume its something to do with the hot element? Many thanks for any replies.