Nomenclature for RS Series
2 = Non-Programmable, Economy Series
3 = 5-2 Day Programmable, Economy Series
4 = Non-Programmable, Value Series
5 = 5-2 Day Programmable, Value Series
6 = 7-Day Programmable, Value Series
Application
0 = Standard Thermostat
Number of Cooling Stages
Number of Heating Stages