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Taco 406 zone control with Taco HAFC fan controller

I have an oil fired boiler and two hydro air handlers with AC. I wired a Taco 406-5 zone valve controller for the boiler zone valves. I wired the hydro fan controller to the nest thermostat and used the common from the air handler to power the t-stat. The x-x end switch from the fan controller I wired to the R-W of the ZVC. Heat does not work. AC works fine. I noticed there is no wiring diagram for this scenario in the Taco control guide. Any ideas what the problem could be. Should the common to the t-stat land on Rc or Rh  Right now it lands on Rh. I was thinking of pulling the common from the ZVC instead of the fan controller. Any ideas are appreciated. 

Comments

  • HVACNUT
    HVACNUT Member Posts: 4,190
    Common doesn't land on Rc or Rh. It lands on C. The thermostat is getting powered from the fan control so 24v goes to Rc. W on the thermostat should energize a relay to close XX.
  • Big Ed_4
    Big Ed_4 Member Posts: 1,775
    Yes you went off on a tangent wiring the end switch to the fan .
    I have enough experience to know , that I dont know it all
  • Swoosh172
    Swoosh172 Member Posts: 2
    thanks for the comments. The fan controller has an end switch output that i'm wiring to the zone valve controller. Attached is the wiring diagram of the connections. Is this correct?