Ive understood the bit that I need an rcd for my underfloor heating, I plan on installing the Warm-Up wire type. But do I need to insall another rcd or does the one on the consumer unit count? What I wanted to do was spur off the socket ring main to power the underfloor heating and thermostat. If the rcd on the CU isnt the right thing do I need this http://www.screwfix.com/app/sfd/cat/pro.jsp?id=14770&ts=12012#