Hello all,

I have a 5 zone baseboard hot water heating system, using Taco 571-2 valves. 4 of the zones work fine, but the 5th zone only works when the power head switch is set to "open". If the switch is set to "auto", the pump / furnace won't fire up, but as soon as I push the switch to "open" (with much resistance) everything turns right on. I've swapped other power heads onto this valve and it does the same exact thing, yet they work fine in "auto" mode on the other 4 valves.

Is it possible that I have a valve that is stuck? The heat flows fine with the head set to "open", but won't that mean that it will continually run even after the room has heated to the desired temperature?

Also worth mentioning: with the power head attached and set to "auto", it doesn't work, but if I remove the power head, the pump kicks on right away. I'm guessing that if the valve is closed, it won't want the pump to turn on?

 

Sure, anything is possible!

Yes. If you lock the valve open, and the boiler fires, it will continually heat the space. Taco valves do fire the boiler when you manually open them. Others do not...

Sure... you don't want the pump running with all the valves closed!