Honeywell Rth8500d

I had an old White Rodgers model 1F56W-361 that I replaced the RTH8500D Honeywell.
Y - Y
W - W
Rc + RH - R + Rc
(Heating and cooling)
But the unit only works with batteries. The question is:
There were two other son a white and black which have been recorded. Any ???????? ideas
Is this from a power source that would work without batteries or batteries RTH8500D also backup.

Thank you
Alex

Anyone who has installed the cable probably just installed a cable 6 son. You can certainly make these a source of energy as long as they are available from your control transformer.

WARNING: Make sure the output voltage of your transformer is the same as what is required by the thermostat.

Reading the manual for this stat ( http://www.honeywellcentral.com/ssi/pdf/ ... ) give cross-wiring diagrams to help make this transition.

Good luck!

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