FWIW, my daughter had the same problem in her house with 2 zones. One of the controllers that operate the zone valves was hung up and wouldn't shut off so the furnace and circulator wouldn't shut off. I rapped on the controller with the handle of a screwdriver and it shut off. It made a scraping/whining sound while moving so I figured it was toast. A replacement of the controller head, not the whole valve, was the cure. It's been a few years and so far so good. You may want to identify the relevant zone valve, remove the cover, then have someone turn the thermostat for that zone up and down while you see if the controller operates.
Last edited by DFBonnett; 11-29-2016 at 07:28 PM.