GARYWC explained on 9/26/2016 :
I probably don't have the same thing as you do, but...
I think you are correct.
When it is hot outside you manually set it to the COOL position and it automatically uses the settings as below for the cool settings.
When it is cold outside you manually set it to the HEAT position and it automatically uses the settings as below for the heat settings.
If it's anything like mine:
HEAT uses the heating settings that you program in COOL uses the cooling settings that you program in OFF is just using the off setting where it is off
On mine, an abbreviated set of instructions are pasted on the inside of the front cover (escutcheon) and you can choose what time of day (morning, daytime, evening, night) and what temperature range you desire for those times as well as what exact time (in increments of some size I forget) you want M,D,E N to mean.
We write down the settings in a notebook because the battery runs down and the setting go wonky. It's easier to load them back in if you have them written down. I use the plus or minus two setting for wider sensitivity so that the furnace doesn't have to fire up and shut down as often as it would at the narrower setting.
I'm guessing that you don't have the booklet called "Owners Manual". It might be available online somewhere if you use Google and the model number you may find one.