Both Water and heating valves opening when either system called for

[NikiInCambs]

Replaced the head of a Honeywell 2port valve on heating and wired into an old block (S) like for like. However, when either water OR heating called for, both valves open!
Ideas?

 

[John.g]

Brown wire from switched live, blue, neutral, grey wire from permanent live orange wire to terminal 10, the m.valve end switch connects the grey wire to the orange wire.

 

[Deleted member 120897]

What was the reason for changing the head? I take it this fault is new?