Question about Honeywell Focus 6300B 5-2 Days Programmable Thermostat Heater

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I want to replace the old mercury termostat with new honeywell RTH2300B. I have only 2 wires. should I use W and R, is there any difference as which wire connect to R, which to W? I found that RTH2300B is not listed on honeywell website, is this a outdated model, I bought it today at HD.

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I had the same problem. The two wires were old thread covered rather than plastic insulation. Looks like they used to be red and black. No color code on the baseplate. I called honeywell and the tech said connect to "R" and "W" and it didn't matter which wire went to which post.

Posted on Nov 04, 2011

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R--red comming n the thermostat and white is heat going to the furnace!

Posted on Dec 21, 2009


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