Hey everyone have a quick question regarding a honeywell VR8300A3500 Single Stage Heat Gas Valve and the introduction of a Ecobee3 wifi enabled thermostat with a "C" wire. just want to make sure i am understanding this correctly and have drawn out the right circuit. The TH/TR stand for TH- Thermostat and TR is the common correct? below is my drawn out circuit along with a picture of the valve and diagram of the valve. Thanks. Also i have a 24v hightemp switch in series as shown. enter image description here

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  • just want to make sure this will work the way it is currently drawn. Thanks
    – Anthony F
    Jun 22, 2016 at 23:09
  • What is the + in the diagram? Typically, TR represents the terminal that the transformer connects to, while TH is the terminal the thermostat connects to.
    – Tester101
    Jun 23, 2016 at 2:16

1 Answer 1


The only goof is that the 24V from the transformer is AC so it really doesn't have a + or - side to it -- it's more or less a "hot/neutral" thing instead. Otherwise, what you have drawn out will work just fine.

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