I have some time series data that contains the temperature of the living room, the temperature of the kitchen and the temperature of the master room in a house. Those measurements are taken every 10 minutes.
I want to get the overall temperature of the entire house so I calculate the average temperature across all 3 rooms (let's call it $T_\text{avg}$).
But now instead of having measurements every 10 minutes I want to aggregate my data and make it daily, for this purpose I have been thinking about calulating the average of all $T_\text{avg}$ so that I get an average temperature per day.
My question is, would this be incorrect (taking the average of average values)? I have been told that in some cases this is correct but in others it is not.
Thanks for the help.