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can zone valve controller turn on my IBC G3 boiler? (improper install i think)

fiddlermdfiddlermd Posts: 59Member
I have an IBC G3 20-160. I have 8 heating zones in the house plus DHW.
the installer ran 2 of my zones to the boiler directly (basement and mudroom) and the rest are run off a Taco 506 zone controller.
It seems that unless dhw, mudroom or basement are asking for heat, the boiler will not turn on. I see the pumps working and the Taco lights up various zones as they ask for heat but the IBC just sits still.
I don't understand the various terminology on the settings screen (set point, zone of, etc) so it's a bit difficult to diagnose but I am very technically savvy otherwise so wiring, voltmeters, etc are not scary.
In my common sense analysis, it seem that the taco has a wire running back to the boiler that sends a signal (i measured 26vac on it when all zones of taco are off and 0vac when any zone is on).. that signal should be registered by the boiler and turn itself on.
alternately, since I also have a boiler buddy, it would make sense for the inlet/outlet temperature of the boiler itself to cause it to switch on.. none of that is happening.. i saw boiler temps of <100 and it still won't turn on unless one of the 3 zones mentioned above are asking for it.
please help


  • fiddlermdfiddlermd Posts: 59Member
  • fiddlermdfiddlermd Posts: 59Member
    looking at the status of the set point, i see the following:
    heat output: 0MBtu
    boiler supply: 126f
    boiler return: 120f
    setpoint target: 170f
    regulated: 126f
    outdoor: n/c
    boiler max: 190f
    cycles/day: 21
    run priority: 0
  • kcoppkcopp Posts: 3,417Member
    Is the house comfortable?
  • fiddlermdfiddlermd Posts: 59Member
    edited January 2019
    not unless either mudroom or basement calls for heat.. i found the issue when i decided to turn off the basement thermostat. since the basement usually remains pretty warm due to all the piping, i figured "off" is as good as setting it low.. and then i came home to find a cold house.
    regardless of comfort, i want to make sure that if only one zone calls for heat, the boiler actually responds and i'm not just circulating cold water (which is exactly what happened)
  • kcoppkcopp Posts: 3,417Member
    Where does the end switch on the taco sr control go to?
  • Leon82Leon82 Posts: 653Member
    They probably could have linked 2 504 together and controlled dhw priority with them too
  • fiddlermdfiddlermd Posts: 59Member
    kcopp said:

    Where does the end switch on the taco sr control go to?

    goes to Therm. 4 terminal. if i'm reading installer menu correctly, #4 is not configured at all (Though i'm not sure if those correspond to the wires.. makes sense that it would)
  • lchmblchmb Posts: 2,961Member
    The bottom pair of contacts receives a 0-10VDC (default) or 4-20 mA signal from an
    external boiler controller for direct throttle control. The boiler’s own sensors act as high
    limits only. The user must enter maximum and minimum boiler supply temperatures.
    page 1-34 of your install manual.. have your installer come back and run the wire and set your limits..
  • fiddlermdfiddlermd Posts: 59Member
    i just set 4 to 'set point' and the boiler turned on immediately.. gonna test what happens when all the zones of the taco are off.
    i dont want my installer to come back cause i have a feeling he really doesnt understand this stuff well enough
  • kcoppkcopp Posts: 3,417Member
    edited January 2019
    Have a conversation w/ tech support. They may be able to connect you w/ a local area Mfg rep to fine tune this. The control is super flexible. Not sure if I asked or got an answer… where are you located?
  • fiddlermdfiddlermd Posts: 59Member
    so the newly enabled zone controller is nice now.. however, the 2 zones originally controlled by the boiler, since they're lower priority, are now going into the low 60's .. is there no way to just assign them equal priority to the zone controller? i just want a "if it calls for heat, boil some water" type of setup..
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