Remove the unit from the wall; the model number should be on a tag on the back. The Operating Manuals for many White-Rodgers thermostats can be found in PDF form HERE, however they are not indexed by model number so you will have to download each file in turn until you find the one you want. All of the file names beginning with "0037-" seem to be W-R products.*Disclaimer: I am not a lawyer, despite the handle. Words to live by: "Every creative act results from a sudden cessation of stupidity." -Edwin H. Land, inventor of the Polaroid Land Camera "The problem can always be solved with the materials in the room." -My college Physics Lab Professor