Hi Echo thanks for coming back to me. I've tried taking a couple of more photos and tidied up the wiring a little, so I hope that you can see better. The junction box has 2 x 2 port valves (grey and black 4 cores) both that seem to be on the cental heating pipes, a cylinder stat (white flex-red, black and grey) , and a central heating pump (white flex - twin and earth). The pump next to the junction box is a water pump wired to a spur elsewhere. The wires in the terminals are a follows
Term 1 - neutrals for pump and both valves
Term 2- live for pump
Term 3 - brown from valve-grey wire
Term 4 - brown from valve-black wire and black from cylinder stat
Term 5 - red from cylinder stat
Term 6 - orange from both valves
Term 6 - grey from both valves
Term on its own with red, yellow and red is the old room stat.
I'm pretty certain that I had separate hot water and heating controls before as when I advanced one of them the other I don't think came on.
Thanks in advance for any help.