The reason they even put these holds on these thermostats are on days that if you have a schedule running for when you're at work. What if you're off one day? What if you? What if it's a holiday? What if it's a weekend? Things like that, you could turn these holds on on the thermostat to tell the thermostat to either temporarily hold a temperature or permanently hold that temperature until you turn the hold off. In most cases, that temporary hold is still running the schedule. you're just telling the thermostat.
Hey, I'm a little hot in here today, you know I Just want to adjust the temperature I Don't want to change the scheduling I Don't want to do anything crazy I Certainly don't want to turn on the permanent hold, but you know it's a little stuffy in here right now and you can adjust the temperature to temporarily hold for that moment.
We personally believe that set back programming 7 days of the week is NOT a true energy saving idea. Especially with A/C in the southwest climates where the interior temperatures can reach 90 degrees with the system off for 6 or so hours each day. Why? Because while the interior temperature is rising so are the temps of the furnishings and personal property inside. Lets say by 5 PM the program dials the A/C to come on and reach 75 degrees for the time folks are now home from work etc. Now that compressor is running every minute for likely 3 to 4 hours before it hits the 75 degree mark.
We leave our A/C setting fixed all day and all night, 24×7 and found that the power used is slightly less than going through the hot then cool cycles each day. Plus, during the "peak demand" times of the day, our A/C isn't working 100% of the time, its cycling every 10 to 15 minutes giving the power grid a bit of a break. We are better off leaving the temp set vs. feeling like we are doing good with power when we are not.