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outdoor sensor and thermostat

info43 Member Posts: 51
HI all
I have a gas steam boiler in a 3 story, 6 family building (WM EG-75) with a plain thermostat in the coldest apartment. I am looking to add an outdoor sensor so that the boiler will only turn on if both the thermostat calls for heat and if the outside temperature is under 60 degrees. Any suggestions on how I can do this? Thank you for your time.


    HVACNUT Member Posts: 4,595
    Yes, set the ODR warm weather shutdown mode to 60*. That will overide any heat call from the thermostat.
    Also, I would move the thermostat to the 1st. floor hall. If your not able to run new wires, wireless thermostats are available and can be programmed to lock so nobody can play with it.

    P.S. My Gammy wouldn't be too happy with no heat at 60*, slum lord. Lol :p
    EBEBRATT-Ed Member Posts: 12,015
    Honeywell T675A you can order it on line. It's a air temperature sensor and is adjustable from 0 deg-100deg. The control mounts inside the building. Drill a hole to the ouside it has a 5' capillary tube that will fit through an approx. 1/2" hole. Put the sensor on the north side of the building in the shade. They also make a wether dchield for the cap tube. Run two wire low voltage thermostat cable from this control to the boiler. Connect to R & B in the T675A

    At the boiler disconnect one of the thermostat wires and wire nut it to one of your new wires from the T675A. Connect the other T675A wire to the boiler where you removed the thermostat wire.

    you now will have a outdoor air lockout control
  • info43
    info43 Member Posts: 51
    edited October 2017
    Thank you both for the reply.
    HVACNUT said:

    P.S. My Gammy wouldn't be too happy with no heat at 60*, slum lord. Lol :p

    I guess I'm nicer than the city says I should be :smile:


  • nicholas bonham-carter
    nicholas bonham-carter Member Posts: 8,564
    You would be better off, and more correctly in compliance with the NYC interior temperature requirements with a remote sensor type of thermostat, such as the Honeywell Visionpro. Place the sensor in the coldest heated area of the building, and the control unit in a locked area near the boiler. This will maintain the minimum 62 degrees at night, and 65 during the daytime.
    Running a constant lower temperature is always more efficient, (in fuel usage), and comfortable than the outdoor lockout you are contemplating.—NBC
  • info43
    info43 Member Posts: 51
    @nicholas bonham-carter
    thank you, I like that idea and it should be more comfortable for my tenants.