System has 6 zones. Zone 1 starts fine, but does not stop. Runs through all 6 zones, then everything shuts off EXCEPT zone 1. Found out when I came home after a few hours and the water was running all the way down the block. I had to go into the box and turn off the in-line shutoff valve.

What are we looking at here? Cheap & easy fix, or tough and expensive? It seems the valve that controls zone 1 is not shutting off? Any tips would be appreciated!

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