I have a time series Temperature data coming from a sensor which is collected at a irregular frequency. The data size is ~100K. I have to find the Lower and Upper Bounds for this data to find the normal operating Temp. range. I am planning to follow below steps for computing these Bounds:
Get a Sample data(size 5K) which is normally Distributed
Find the Tolerance Interval of this sample size
My Question: Is this a correct approach to find the Upper and Lower Bounds of data? if not then Statistical Quality Process Control charts should be used here. I am afraid to do that as this data is collected at irregular frequency.