Triton Shower leaking from shower head

silversue_2

Hi, I have a tricky problem with a Triton Aquatronic 1+. Firstly the shower continued to pour water when it was switched off. After 20 mins the water stopped but there is now a constant dripping down the shower hose and out of the shower head. I have replaced the Pressure Relief Device (still drips); replaced the stabiliser valve seal (still drips); tested the solenoid coil and reading is 3.525. I'm guessing I need to replace the 'solenoid valve assembly' complete which would require a plumber. Could anyone confirm it sounds like the solenoid or suggest anything else I can try?

I reckon it may be cheaper to replace the shower unit altogether if I need to call a plumber and probably have to wait longer.

Thanks in advance for any advice