EcoBee Smart Si Wifi Thermostat
Hey all, New to the site as a member, but a frequent reader of many of the posts here. I'm one of those that likes to tinker and tweak my trailer. And sometimes some of the mods lean more towar...
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Awesome! Thanks for letting me know that it worked for you. I'm actually a bit surprised how many searches on various groups turned up 'nope can't be done'...
So, I ran some tests on the weekend to see what was flowing. I have a Dometic DuoTherm board, and although it doesnt show it on the wiring it seems that the only hot wire that goes to the thermostat is a +7.5V. Not sure why they step down from +12V to 7.5V, but it seems the way that it is.
Ran the voltmeter between RC/RH and W & G while furnace was going and saw that Im getting about -12.5V on the return. So...
As it stands right now I picked up a 24VAC transformer and am planning to run juice from a concealed area to the Tstat, then picked up 3 x 90-290Q fan relays. So will run the tstat as a stock 24V but intercept the return feeds with the relays and tap into the existing setup.
However, I'm wondering if I can recommission the current red 7.5V wire to a 12V up in the control box (eg think there is an unused filter or solar 12V lead up there). Then would save me the whole relay steps.
Note: that is anyones goes the 24VAC route, it would work with ANY smart tstat requiring a common C wire. I likely wouldn't pursue this route if I couldnt easily fish the wires I need to keep it all concealed, but the way my setup is, I can pretty much do so without a relay box or transformer being seem.
This weekend if the project, so I'll share results.
Thanks again for letting me know your success with the Smart Si!
So, I ran some tests on the weekend to see what was flowing. I have a Dometic DuoTherm board, and although it doesnt show it on the wiring it seems that the only hot wire that goes to the thermostat is a +7.5V. Not sure why they step down from +12V to 7.5V, but it seems the way that it is.
Ran the voltmeter between RC/RH and W & G while furnace was going and saw that Im getting about -12.5V on the return. So...
As it stands right now I picked up a 24VAC transformer and am planning to run juice from a concealed area to the Tstat, then picked up 3 x 90-290Q fan relays. So will run the tstat as a stock 24V but intercept the return feeds with the relays and tap into the existing setup.
However, I'm wondering if I can recommission the current red 7.5V wire to a 12V up in the control box (eg think there is an unused filter or solar 12V lead up there). Then would save me the whole relay steps.
Note: that is anyones goes the 24VAC route, it would work with ANY smart tstat requiring a common C wire. I likely wouldn't pursue this route if I couldnt easily fish the wires I need to keep it all concealed, but the way my setup is, I can pretty much do so without a relay box or transformer being seem.
This weekend if the project, so I'll share results.
Thanks again for letting me know your success with the Smart Si!
