I am removing an old stndard thermostat and replacing it with a honeywell programmable (RTH221B) thermostat. There are 4 wires red, blue, green, and yellow-There is a hook up for Y=, G=, Rh=, Rc=, W= can someone tell me what goes to what. I have tried and only the fan comes on... Pleeeaaassee help help help... thank you

On the old tstat,, what tag did each color wire go to?you should have written down what each color wire went to,, if you didn`t you will need to go down to the furnace end and see what each color is hooked to

It should be red wire to rh with a jumper from rh to rc
Green wire to g post
Yellow wire to y post
White wire to w post ( but this is maybe what someone used the blue wire )

Be sure to kill the power to furnace (breaker ) before attempting change

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