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Tekmar 256

I am buying a tekmar  256. I have 4 zones on a taco sr504  relay. Terminal  7 on tekmar  256, should be wired to R on thermostat. Should  I  connect all 4 red wires to terminal  7 on tekmar?


  • pedmec
    pedmec Member Posts: 208
    no. you will take 24 volts from 504 and use that voltage to create the voltage for the heat demand . connect the 24 volt to 8-9 with power on 8. then run #7 to one side of the x-x terminals on the sr504 and on the other side of the x-x terminals return to #9 terminal on the tekmar. this will initiate a boiler call with a call for heat. thermostat should go to sr504 on the zone thermostat terminals on top of sr504.

    or you can jump from 7 to 9 and have the tekmar control maintain a constant boiler reset temperature and when the zone calls it just will turn a zone circulator on. normally do that on larger systems.