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T8400B T Stat

You may want to check the va rating on the t-former powering these t-stats and also chect to see if there is any voltage drop. What is the actual voltage on the t-stats when not calling for heat? Are the Stat lines excessivly long?


  • Bob Sweet
    Bob Sweet Member Posts: 540

    The 8400 power stealing T Stat, been having issues with displays going blank at intermitent times.

    6 T Stats in all, wired to simple 6 zone controller, customer just called to inform me that when he turned one T Stat on, all 6 went blank. This isn't the first time this has happened, eventually they seem to reset themselves and work fine, curious if you have any insight to this problem. Thanks
  • carol_3
    carol_3 Member Posts: 397

    Haven't heard of this before and I'll see what the engineer says. In the meantime, let's remember that a thermostat isn't a load and has a very small amp draw. As I remember, these stats do 80 milliamps. Of course, each controls a load that does have an amp draw. I'm on vacation, for the rest of this week, so expect to hear from me next week.
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