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green light

lisasrg Member Posts: 1
has a Utica MAC-150 Combi which intermittently has a flashing display screen. The screen is green in color when flashing.

There doesn't seem to be any other issues with performance of the boiler...working / operating perfectly otherwise. Any idea what might be causing this?


  • kcopp
    kcopp Member Posts: 4,432
    bad connection?
  • hot_rod
    hot_rod Member Posts: 22,142
    Does the manual mention anything? Maybe it is a service due alert?
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 7,835
    edited May 2023
    The "Green '' appears to be the LCD backlight. Are there any numbers or letters on the display when this flashing occurs? Does the flashing have a pattern? Is the flashing consistent during the occurrence or is it random? (I understand intermittent, I was asking about when the intermittent flashing occurrence happens, does the flashing have a pattern during the event?)
    Edward F Young. Retired HVAC ContractorSpecialized in Residential Oil Burner and Hydronics
  • mattmia2
    mattmia2 Member Posts: 9,640
    Is there by any chance something pressing one of the buttons or one of the buttons stuck down or something leaking on one of the buttons?