I have an 11 zone system. I have two control boxes that have 4 valves each in them. Should there be a valve for each zone or could one valve pull double duty? I think I am missing a box. Zone 6 does not work. In one box the valves control zones 3,5,7,8. The other boxes valves control zones 1,2,9,10. Zone 4 works fine as well as zone 11. I see the blue wire for zone 6 but it is in both boxes. Is it most likely I am missing a box or is there a way the wiring went bad?