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multiple (hot water) zone digital thermometers....

Does anyone know a way of possibly wiring a single digital display thermometer that has only one Supply lead and one Return lead onto multiple zones? I has hoping to purchase one thermometer and maybe wire in a multi position switch of some sort that had leads to & from each zone.


  • Jean-David Beyer
    Jean-David Beyer Member Posts: 2,666
    Think what you are asking.

    A thermostat measures the temperature where it is. As the resident philosopher at a company I once worked for remarked, "A thermostat acts to keep itself comfortable." If you have only one thermostat, you have only one zone. No matter how you wire up that one thermostat, you will have one zone. It might be more complicated than the usual way to operate a single zone if you had multiple zone valves or multiple zone circulators, but as a practical matter, you would have only one zone.
  • Plumdog_2
    Plumdog_2 Member Posts: 873
    It could be done

    But you would need a separate pair of sensors for each zone, and then tie them in to your display with a bank of toggles or a rotating switch of some kind. There should be something like that on the market already, I would think.
  • Jean-David Beyer
    Jean-David Beyer Member Posts: 2,666
    I really do not think so.

    If you have separate sensors, a separate one for each zone, and switches for each one so that only one circulator or one zone valve is enabled for each sensors, what happens (no matter what the thermostat is doing) to the disconnected zone valves or circulators? They are, most probably, off. Or in the case of some zone valves, perhaps they are on. In either case all but one is not being controlled by a sensor. You would have to hang around, noticing the temperatures of the various zones, and enable the sensor and circulator or zone valve, of the coldest zone. You might,  if the thermostat has a high enough contact rating, to enable the actuator of all the cold zones. But in that case, why bother with a thermostat at all? Just have a switch in each zone and turn it on if it is too cold, and turn it off when it is warm enough. Sounds like more of a nuisance than a convenience to me.
  • Paul48
    Paul48 Member Posts: 4,470

    Reread his original post.I think he just wants to be able to check the supply and return temps of each zone with a single readout. He wants to use a selector switch of sorts to choose the zone he wants to check.Although, I have no idea why he wants to set this up permanently.
  • Jean-David Beyer
    Jean-David Beyer Member Posts: 2,666
    I agree...

    You could interpret the individual posting to say it was intended to read the values of a system's multiple sensors, and have no intention to control the temperatures directly in the usual way.

    I also have no idea why anyone would wish to do that. It is such an alien concept to me that it never occurred he might have meant that. Why not just have plain thermometers and walk around and read them. How big is a house anyway?

    At the other extreme, why not run the sensors through an analog to digital converter into a computer, and wire outputs from the computer to run parts of the system? Maximum flexibility, though the complication might not be worth the trouble and expense, and might bring problems because of the added complexity.
  • SWEI
    SWEI Member Posts: 7,356
    As usual, it depends...

    on how far apart are the locations where you want to read temperature, and the type of sensors used. If they are 10k thermistors, you have quite a bit of range - but if they are platinum RTDs it may not be so simple.
  • john p_2
    john p_2 Member Posts: 360
    maybe alittle extreme but....

    that is exactly what I want to be able to do...monitor each zone temperature differentials (6) and remove my old dial thermometers that are hard to read. I'm sure there is a control out there for this just can't find it.
  • Mac_R
    Mac_R Member Posts: 117
    Here is your solution

    Honeywell Prestige HD Thermostat with the wireless focus Pro system.  With the Prestige thermostat you can get a Portable Comfort Control.  It is a little remote that you can view and change zone temps with.  You can also tell the system to use the remote as a thermostat in place of a wall mounted thermostat.  I have on of the Prestige HDs in my home with the remote.  When I put my daughter to bed we use the remote to keep her room at 72.  The rest of the house gets a little warm.  But her room stays at what we want. 

    The Prestige AIQ 2.0 has a board down at the system and only uses two wires to the stat.  Everything is done through Red Link Tech.  It also allows you to expand your system with a humidifier, dehumidifier, UV lamps, and fresh air exchange latter on if you have forced air. Simple to install and I think will do what I think you are asking for.
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