Re: forced hot water heat question
frankjc ..... I agree with NashuaTech ..... you have to take this one step at a time or you get yourself running in circles.
NashuaTech is very knowledgable with this subject where I'm a novice.
Hopefully this won't add any confusion with my 2 cents...........
seems you have 2 zones .... assuming zone 1 is the main level ..... zone 2 is the upper level.
Zone 1 seems to work fine and the one in question is zone 2.
Since zone 1 is working fine ......... is it possible to disconnect the wires from the controller for zone 1 and attach the wires for zone 2 in it's place ?
Then turn up the thermostat on the main level .... the circulator pump for zone 2 should start and send warm water to the second floor.
If it does then you have determined the problem is likely associated to the R845 or the wiring.
If it doesn't then you have determined that the R845 isn't the issue.
Just a thought.
"" an ounce of perception -- a pound of obscure "