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New thermostat wiring Q

In the process of installing a new wireless thermostat (pro1aq t955w) for use with my existing boiler - single stage/single zone Slantfin SE-140.

The boiler currently has a thermostat connecting to the T & TV terminals on the control board. If I'm understanding the new thermostat wiring correctly, I'll need a relay of some sort in the loop to take the energized output from the new thermostat and bridge together the T/TV terminals.

Yes/No? Any suggestions?


  • drhvac
    drhvac Member Posts: 190

    yes, if you only have one zone and no zone valves, you will need a relay. w from your stat would go to the coil of the relay, and the t & tv terminals would go across the n.o contacts.
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