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Thermostat can't activate shared pump to boiler

Alex488 Member Posts: 1
So I got an ecobee thermostat in one zone and a regular old school thermostat in another zone. They share the same return pump to boiler. For whatever reason, the ecobee stopped being able to activate the pump. When I turned temp up on conventional thermostat, everything was fine including green light on relay board turned solid green, pump starts, heat comes. When I turned temp up on ecobee, the green light on relay board flickered but didn't go on, no pump, no heat. For me to get heat in zone controlled by ecobee, I have to turn temp way up in the other zone so the pump is running. Does anyone know what issue I am dealing with? Btw, it's been having this issues on and off recently


  • Alan Welch
    Alan Welch Member Posts: 270
    Does each thermostat open a zone valve? You may have a bad end switch on the zone with the. Ecobee.
  • HomerJSmith
    HomerJSmith Member Posts: 2,511
    Insufficient data to make a analysis. Maybe the ecobee thermostat need a jumper between the R & RH. Did it work before and you are now experiencing problems or is it a new addition?
  • Jamie Hall
    Jamie Hall Member Posts: 23,650
    Batteries in the Ecobee?
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • krimm
    krimm Member Posts: 3
    edited February 2018
    We actually have the same setup but my ecobee cooperates well with our old thermostat, so far. Did you install it on your own? Maybe try asking for professional help?
    HVACNUT Member Posts: 5,888
    Is the Ecobee 24v powered or just R-W? You might need a common or a resistor.