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What this box for with the red light?

Danielll Member Posts: 1
edited February 9 in THE MAIN WALL
The thermostat stop working last night and the heating stopped working, this box has never been touched and always been on red however when we put in on green the heating sort of starts to work


  • PC7060
    PC7060 Member Posts: 330
    Hi Daniel, Where are you located? Can you send us a picture from a bit farther back that show the boiler (or furnace)?
  • kcopp
    kcopp Member Posts: 3,739
    From the looks of this its in the UK.
  • PC7060
    PC7060 Member Posts: 330
    kcopp said:

    From the looks of this its in the UK.

    That's what I thought from the electrics.
  • MrScott
    MrScott Member Posts: 2
    Can you get it (gently) off its mounting and take a picture of the back?  Seems like there might be labels back there.
  • JDHW
    JDHW Member Posts: 17
    The box is a receiver for a wireless thermostat (probably honeywell). When it is working normally it show nothing or a green light when calling for heat. I red light means not connected to the the thermostat. Have you changed the batteries in the thermostat?

    John W.
  • JimUK
    JimUK Member Posts: 0
    I'm a home owner not a pro, but am in the UK.

    Yes, that is the receiver ( aka"Relay Box" ) for a RF linked room thermostat.

    The room stat and receiver combination are available under a few brand names.

    I think the box to the left in the picture is the timer programmer ( time intervals, not different temperatures ) also seen with various brand names.

    As suggested, the red light indicates a loss of communication from the room stat.
    The Relay Box probably then operates in a "fail safe" mode; which might depend on options set when installing it.

    The room stat will have some indication of problems, low battery, internal fault, loss of RF communications.
    If it just needs fresh batteries then RF communications should resume ok, it should not need a re-binding procedure ( but ... ).

    If the relay box behaves as mine does, then pressing the button on the box gives "a temporary overide" of the relay position.
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