Heating, Air Conditioning, Fridge, HVAC/Thermostat Hookup


I want to change my cooling only manual thermostat to a programmable.  I bought a Honeywell TB8220U.  On my old thermostat I have two sets of wires coming to it (R,G,W each set).

Old thermostat: R1 goes to "R", G1 goes to "Y", and W1 is not hooked up.  R2 & G2 are not hooked up and W2 goes to "Y" (with G1).

New thermostat has way more hookups, and I'm not sure if I should just hook it up the same or if it should be different with more hookups.

Old thermostat does not have option to just turn on fan which I would like to do.  Not sure if that matters.

I have a some concerns with your set up. If you wire it up as it is now, the fan will not come on with a fan only command.  The fan will only come on with a call for cool.  Normally the red goes to R, which is the 24v power in.  Yellow goes to Y, which is a call for cool. The Green goes to G which controls the fan.  You might get lucky and wire R1 to red, G1 to G and W2 to the Y.  Just set up the stat for conventional use.


Heating, Air Conditioning, Fridge, HVAC

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Craig HVAC Expert


I have been in the HVAC field for the past 18 years. I can help with most HVAC questions. I work on commerical buildings for the most part, and have yet to find anything I could not troubleshoot and repair, when repairable. I work on small 1 ton units to a 2500 ton chiller. Troubleshoot air flow, elect, and control problems. I attend regular classes to keep up with the latest and greatest.


I work on commerical sites, hospitals, gov't buildings. I can troubleshoot just about anything in the HVAC business.

5 years trade school, VFD training classes, Liebert factory training, some York and Trane factory training.

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