I'm hoping to get some help with this before I call someone in just in case it's something I can do. I purchased a house recently. I saw it in February and the heat was working with the people living in it. I didn't get to take ownership until June. I turned on the system and it fired up the boiler, gave me a reading of the boiler temp and everything was sounding good. Then it gives me a fault and it reads bd. I was told it's the mixing valve switch not being turned on. I can't find any switch anywhere for it. If I move the valve on the box attached to the mixing valve, all the pipes get warm, but nothing ever heats my rooms.
On a side note. I have 2 zones. My second floor is on Zone 1 and Zone 2 is my first. I have a Vitotrol 300 on my first floor that never connects. It just does the little progress bar thing. Any help would be greatly appreciated. Thanks!