Hi Robert, If the shower is less than 2 years old its still under guarantee. If it is not still under I think its broke. One thing you could try is go back to the manual you got when you bought it and look at installing it from scratch. Be sure to turn off the power to the shower in the fuse box and open the bleed value just above the filter. Its all in the manual. If you done have one il scan the page and send it to you.
Gareth, January 2011