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New Honeywell VisionPro 8000

I installed this in April to replace an original VisionPro, which I use with a remote indoor sensor, with my Peerless 211A.
On Friday, I had an error message on the thermostat screen, alerting me to a remote sensor problem.
I managed to get a replacement thermostat, and sensor, before Johnstone supply closed.
I first changed the remote sensor, and found the temperature readings off the numbers. Then replaced the thermostat itself, and all seems to work alright, except for one feature: the display which I set up to be on continuously, is only on by demand when I touch it. This leads me to believe that the voltage powering the thermostat is lost somewhere in the wiring between. This would maybe explain the message, because of the batteries being depleted could not power the remote sensor, (as I had a C-wire, I did not think about the batteries).
Does this display problem point to a no power for the T-Stat problem? It works adequately now, but maybe only on battery power.
Im wondering how to check this problem out, as the boiler is controlled by a "fan center"!--NBC


  • Fred
    Fred Member Posts: 8,541
    edited November 2015
    Bad transformer or loose connection maybe? Probably is running on battery and Display won't run continously to conserve battery power.
  • KC_Jones
    KC_Jones Member Posts: 5,431
    If you don't have power it won't let you turn this feature on. So if it's unavailable I would say it's not getting power. Have you tried checking voltage at the thermostat between I think it's R & C?
    2014 Weil Mclain EG-40
    EcoSteam ES-20 Advanced Boiler Control
    Boiler pictures updated 2/21/15
  • ChrisJ
    ChrisJ Member Posts: 14,956
    Whenever I forget to turn my boiler's power back on my VP doesn't stay lit and that's a reminder for me. Turning the power back on causes the VP to light up within a few seconds.

    I'd say missing common would be my first bet from your description. As was said you can't have the continuous backlight without a common and obviously the system is working so your R and W must be good.
    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
  • Now continuing on this diagnosis, and I find I have 24 volts between R (transformer hot side and C), but I didn't know if there was enough current, so I replaced the fan center.
    I also hooked up another transformer to R and C, on the bench standalone to see if some wiring problem behind the fan center, could be suspect. Still no continuous backlight.
    Next stop Honeywell tech support. In the early days, Bill@honeywell would have quickly pointed me in the right direction, but he is alas no longer there.--NBC
  • 6 months ago, I tried the eco bee thermostat, and when I hooked it up, the relay chattered on the old fan center, which makes me think there was something wrong with the fan center transformer, and now I think it may be the wiring behind the fan center.--NBC
  • I tried putting the jumper from Rc to R back in, and bingo, the backlight is continuous!--NBC
  • ratio
    ratio Member Posts: 3,512
    IIRC the stat itself operates off of Rc, implying that the C must come from the same xfrmr. Using the C from the Rh xfrmr won't work out very well, & could even let the smoke out.
  • hvacfreak2
    hvacfreak2 Member Posts: 500
    And just to make things interesting there are now 2 completely different 8000 series stats on the market.

    Mechanical Enthusiast

    Burnham MST 396 , 60 oz gauge , Tigerloop , Firomatic Check Valve , Mcdonnell Miller 67 lwco , Danfoss RA2k TRV's

    Easyio FG20 Controller

    JUGHNE Member Posts: 10,798
    Even the 5000 series state to connect the common from the cooling transformer if 2 xfmr. But nothing mentioned about keeping the jumper in place if only 1 xfmr. (I'm always tempted to remove it because with it there the 18 ga wire is a pretty snug fit).

    And I always try to have a common at t-stat, so thank you NBC for doing the leg work for us on that one. ;)
  • Honeywell tech support were no help on this. I even registered to join their forum, but have not received any confirmation after 4 days that I can post my question.
    This is what make this forum so valuable. Dan and Erin could make a service available to all the companies for questions pertaining their products. rude troll-like bashing letters could be screened out.
    It's obvious that these companies are ill equipped to provide these tech support options, and therefore need help from those who can do a better job.
    As more and more products are sold directly to the end user, in a DIY install, there will be a great need for this information. In addition, the products are becoming so much more complicated.
    The next problem with a Visionpro 8000, is one which controls a hot water boiler for heating, as well as a big A/C unit. in heating mode, this thermostat is not getting power, so I suppose i should run a common wire from the boiler transformer, after checking the polarity.--NBC
  • ChrisJ
    ChrisJ Member Posts: 14,956
    I think I remember discovering this a while back but I forgot.
    I accidentally dropped the stupid jumper and couldn't find it so left it off because I don't have any cooling. I quickly realized the backlight wouldn't work so made a homemade jumper.

    I completely forgot, I'm sorry NBC. :(

    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment