During our many engaging conversations in Colorado we talked about a "hot common" or "open common". I was talking to Fimco about a zone that was stuck on due to it having the common hot, I thought I miss wired a pigtail. He talked about an irritrol (I think?) controller that had a hot common. Fimco explained to me how it worked and also how the RM can create a hot common. Still cloudy. Any one up for rehashing this?