My old instructor always said "read the instructions" But; really, most thermostats tell you the correct wiring on the back mounting plate, with thermostats getting so complicated I read the instructions, and I even keep a binder of instructions for different brands. Make sure to mount the thermostat on a centralized inside wall where it wont get bumped, or be influenced by false temperature variations, avoid outside walls and place it about 3 1/2 to 4 feet high.
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