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Outdoor Temp Sensor

HankSnowHankSnow Member Posts: 2
edited November 14 in THE MAIN WALL
I just had my boiler replaced - Well Mclain CGA-8. The previous boiler had an outdoor temp sensor however the tech didn't seem to think it was needed with the new one. The control module does have an input for the sensor.
Is there any advantage in adding the sensor in terms of reducing overall gas usage? I live near Edmonton Alberta.



  • EdTheHeaterManEdTheHeaterMan Member Posts: 1,061
    edited November 12
    Yes, there is an advantage to staging the water temperature in the radiators based on the outdoor temperature. We have been doing it for years. Now that this technology is so affordable with tiny microprocessors that can be added to basic heating controls for next to no cost to the control manufacturer, we are seeing this technology everywhere.

    There are still some old-timers (Like Me) that have a difficult time operating our cell phone without the help of grandchildren. That said, the man you spoke of just decided for his own convenience to make his life easy by telling you that they don't do that much. see below

    The savings will vary from job to job, but it may be as little as 4% or as much as 25%. Can't say where you will fit in.
  • EdTheHeaterManEdTheHeaterMan Member Posts: 1,061
    There is not much information available on the outdoor sensor for your control. I'm not too sure that there is any benefit to using the sensor in your case. In most cases where an outdoor sensor is attached to a control, there are adjustable parameters to cover the use of the outdoor reset function. The WM boiler control module you have has no such settings that are field adjustable in the installation and operation manual. Your contractor may be correct in this case.

    For more information, contact Weil McMclain tech support directly for more information. If you find something interesting, we would like to know about it here.
  • Big Ed_4Big Ed_4 Member Posts: 1,486
    Yes, get it to work . Why fire the boiler for the coldest day of the year all year long .Go for less fuel usage and comfort . Flatten the curve for comfort . The on and off you will notice if not `programed for what BTU is needed for that given time ...
    I have enough experience to know , that I dont know it all
  • EdTheHeaterManEdTheHeaterMan Member Posts: 1,061
    @Big Ed_4
    Does that outdoor sensor have a reset function on the WM control? Are there any adjustments to adjust the reset curve?
    The last one I came in contact with was ambiguous as far as the function of the ODS. The economy dial is only addressing boiler temperature according to the manual.

    If it was my job, I would call WM tech support and ask John or Gary about the outdoor sensor/control function. (If they are even there anymore)
  • HankSnowHankSnow Member Posts: 2
    I spoke with WM and got the instructions for the outdoor sensor and now have it on order. I'll give an update once installed. Thanks for all your help so far.

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