I have a 16 zone IRO and I am only using 9 of the zones. 8 on the left side and 1 on the right side. I only have 1 common wire. I put it on the left side and everything works fine for the first 8 zones. The 9th zone won’t fire up and of course I assume it’s because the right side doesn’t have a common wire. I tried to cheat and ran a write from the left common to the right and that didn’t work.
Any suggestions or do I need that second common?