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Thermostat and temp probe help

I've recently installed a 4-zone radiant heat panel (one zone priority) with a Taco control box that operates four separate pumps. I also installed a Electro Industries EB-WX-27 boiler. I'm planning on utilizing 2 of the zones under the concrete (one in the garage and one in the house). The 3rd zone may be used for under a portion of the 2nd floor to provide supplemental heat if required. The 4th zone will be used to melt ice from under the driveway outside.

I'd like guidance on a good thermostat with wifi capabilities so that I can monitor the system when I'm away for weeks at a time. From reading I'm aware that I should have two temperature sensors to go along with the thermostat as well and not to rely on air temperature above the concrete.

Can someone suggest temp sensors and a good thermostat given my installation equipment? I'd also very much appreciate a wiring diagram if possible. If there are places on this website where I can look for myself I'd certainly do that as well.

Thanks in advance, Darin


  • mattmia2
    mattmia2 Member Posts: 5,978
    I have a suggestion, if you are going to be away for weeks, you might want to size the system to use a propylene glycol antifreeze mix and run it with antifreeze so if something fails and you don't get there in time or can't fix it, it won't freeze up.
  • Tcatflyer
    Tcatflyer Member Posts: 3
    Yup, that's the plan. I've got it sitting here waiting to be diluted and put into the PEX. Not excited about the reduced heating capacity due to lower specific heat but better safe than sorry. Thanks.
  • Jamie Hall
    Jamie Hall Member Posts: 19,401
    For what it's worth, the loss in heat capacity isn't the problem with glycol -- it's that the heat transfer rates aren't as good, so it needs to run at a slightly higher temperature. Not usually a problem.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • hot_rod
    hot_rod Member Posts: 16,859
    A bit more pumping power required also with glycol fluids. Use the fluid derate factor usually shown on the bucket at different % of mix.

    I think Ecobee has some wireless sensors that can be used with their stats.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • Tcatflyer
    Tcatflyer Member Posts: 3
    From what I can see on Ecobee's website the associated sensors are air temperature sensors and not for measuring concrete slab temp.

    Thinking on that a bit more and considering the Taco control box it appears that I perhaps it's best to get separate wifi thermostats for each zone. I'm assuming the thermostat would have terminals for the slab temp sensor and then also terminals for power and wires that tell the Taco control box heat is required in that particular zone. Again that's why I'm also looking to see wiring diagrams if they exist on this website. But first I just need info and the thermostat(s) and sensors so I can get them on their way.

    From what I can tell all the wires to the thermostat (except the ones going to the slab sensor) would terminate on the taco control box. So it would get it's power from there and tell the control box when that zone needs heat. And in return the taco control box would tell the boiler heat is required (thru a relay). Sounds like the boiler has perhaps four different power use levels that it will self modulate by adding or subtracting heating elements in order to satisfy desired temperature output which is set by a small dial on the front of the boiler. Lastly if the off-peak controller tells the boiler it can't have power for some time there is another relay on the boiler used to turn it off. If all my assumptions are correct then in my mind this control scheme is complete and everyone should be able to do their jobs. Again this is from what I understand about reading here and there and not knowing the whole story. So I'm looking for a general schematic that shows how all the components are wired together.

    Thanks, Darin