If I am in the shower more than about 5 mins the water stops flowing, do you no how to fix this.

Bev, January 2017

Is the red overheat light coming on? it may be that the filter needs cleaning. this may be something you feel happy to do yourself but might need a qualified expert to do for you. alternatively there is a pressure switch that can and does fail.
I would suggest however that you ask someone to come and look at this for you. opening the shower covers exposes the electrical supply and as you are asking this type of question it would suggest that you are not possibly aware of all the risks involved. Showers are dangerous to work on if you don't know what you are about and i don't want to see anyone end up hurt or worse

Kenny, January 2017

You would probably do a Google search for - say - "Red ring expressions 500 faults" and have a look ast results that come back.

You could find some forums dedicated to showers and ask there.

No, you want other people to do the leg work.

From experience, it sounds like the solenoid valve coil has failed.

See this page, which will list the part (its item 2): https://www.showerdoc.com/redring-expressions-500s-9-5kw-53673501-shower-spares

See also thi spage: https://www.showerdoc.com/redring-expressions-500s-9-5kw-53673501-shower-spares/question/on-off-on-off-90117

And finally this page: https://www.youtube.com/watch?v=NzJjzWqxesc

Anon, January 2017