As of 2015, Rheem thermostat manuals can be found on the Rheem website. The site has a PDF document query that returns the appropriate documents for the model requested.
Rheem thermostat manuals may be necessary if the thermostat ever malfunctions or if the instructions for programming it are ever lost. Accessing the manual via the manufacturer's website is the best option as it ensures the documents are reliable. The PDF version of the manual can be saved to a computer or thumb drive for future use.This saves time if the manual is needed as it will be locally available, and a search for it will not be necessary.