Need help finding a trend

[marcelo67]

I need help finding a trend in my data. I am comparing air conditioner units before and after service and would like to calculate how long it takes for the air to go from room temperature (when the unit is not running) to its coldest point after the unit turns on.

I have an excel sheet with the temperatures read in one minute intervals. A/C units cycle several times per day and they take several minutes to reach their maximum cooling ability. The problem is that the cycles change throughout the day. For example it might turn on at 8:00 am and take 5 mintues to reach its coldest point and then turn off at 8:10 (in this case I would like to know that it took 5 minutes). It will then kick on again at 8:42, take 7 minutes to reach its coldest point, and turn off at 8:55 (in this case I would to know that it took 7 mintues). Repeat this throughout the day. Once I have all those numbers, I can then compare the averages before and after.

Is there a way to see how long it takes to reach that coldest point at the beginning of each cycle?

Any thoughts or ideas would be great!

Thanks,
Marcelo

 

[tstevens]

You may want to create a line graph for each ac unit. This way you can see the lowest temp. reached as well as measure between the highs and the lows to estimate the time.

 

[marcelo67]

Thanks for the idea. I have a week worth of data to graph and that ends up getting a bit cumbersome to look at. I will try to break it down by day maybe to see if that helps. Due to the sensitivity of the numbers I would really like to have a number to look at to be more precise.

I will give it a shot.

Marcelo