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Taco sr502 to Honeywell Smart Thermostat
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.