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Taco sr502 to Honeywell Smart Thermostat

chrito26chrito26 Posts: 3Member
I read through a bunch of these forums for adding a C wire. I can get the thermostat to power on but it never calls for heat. I have a two zone Taco SR502 board with two zones. One going to a hot water heater and the other to my gas furnace. Please ignore the quality of the wire ends. I have moved them in and out of my old thermostat trying to get this to work and they are longer than they need to be for the new thermostat block.


  • chrito26chrito26 Posts: 3Member
    edited April 2019
    Zone 2 - The farthest to the right top row is what I added. I ran a new wire down to the board as the existing was only a two wire. Curiosity is why zone 1 & 2 were different starting out with white on the opposite side. If I connect my old thermostat, a rotary dial old school model, it works fine with White going to W and Red going to R.
  • chrito26chrito26 Posts: 3Member
    edited April 2019
    OK, not sure how to close this but bottom line is ;)

    The schedule was overriding the heat setting. I turned off the schedule and it fired right up.
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