The Shower Doc has parts you require complete with a drawing and write up on how to set up.
Link here http://www.showerdoc.co.uk/shower-spares/dolphin/heater.html
Dave
January 2011
I have exactly the same problem, any details of where i can find the parts would be much appreciated.
Derek
December 2010
Can you give me the contact details of this chap in Kent?
I need a replacement contacter switch.
Hanneke
July 2010
I have just replaced a Dolphin riviera mk iv heater block that was refurbished, via ebay!. A chap in kent seems to have the know-how. As for the contactor switch I dont know.