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Common 24v C wire

Bill14174Bill14174 Member Posts: 2
Hello, I’m swapping out my old White-Rodgers series 80 thermostat for an Emerson Sensi Smart ‘stat. My old W-R ‘Stat did not have a common C wire; just red & white wires. There is an unused blue wire. Looking at my Honeywell RA832A, I see the red wire connected to the upper “T” terminal & the white wire connected to the lower “T” terminal. The blue wire was clipped off. Is there a terminal on my RA832A I can connect the unused blue wire as a common 24v C wire so I can wire up my Sensi Smart ‘stat?  I’d like to avoid using an additional 24v C Wire Adapter as a work around. 


  • HVACNUTHVACNUT Member Posts: 3,581
    Nope. You can use the adapter or change the relay to a Taco SR501 or equivalent the offers a 24v R-C terminal block.
  • Unfortunately, they don't give you a "C" terminal.

    I'd switch it out for a Taco SR501.
    Often wrong, never in doubt.

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  • Bill14174Bill14174 Member Posts: 2
    Thanks for the tips on Taco SR501!  If/when my RA832A fails I’ll swap it out. Until then I’ll stick with my 24v C wire adapter work around.  

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