X-intercept in Temp Profile

For the temperature profiles, the More Info gives the slope and the x-intercept. It would be more useful to see the y-intercept. That is the temperature for which the system can no longer keep up based on the trendlines from the data.

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The “More Info” gives you two values for each trendline: slope x and y-intercept b.

Using the line equation y = mx + b, you now have only x and y remaining. To find the outdoor temperature x where the system can no longer keep up with demand, simply set y to 0 and solve the equation (y - b) / m = x.

I understand that, but would be nice to have the value displayed outright. I’ve done the calculation and got the answer I was expecting. It’s just a more useful value to show than the one currently displayed.

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Fair enough! :slight_smile: I modified the post title as that would technically be the “x-intercept”. I can certainly look into adding it.

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You are correct that is the x-intercept. Thanks for looking into adding that.

When I got my new HVAC this year, I was curious as to where the trendline crossed the x-axis and watched it change as it acquired more data. I only recently discovered the More Info option, but had to do the calculation to get the number I wanted.

Thanks

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Ooooo, Algebra. I thought there’d never be any use for it. Just kidding. I hadn’t really thought about the use for that until now. Thanks for providing the data. I’m good from -105 to 106!

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Since it illustrate the capacity limit for each system component, the x intercept certainly is good info !

Some kind of graphical history of those intercepts (and slope) would be a really nice way to illustrate the performance evolution/degradation of each component… but with a lag since its time-averaged… (havent got into how things are calculated, maybe this could be easily resolved?)

The addition of a couple of ‘dots’ in the temperature profile showing the “latest calculated values” for each system would provide some similar performance measure (actual vs historical average).

This would really be great info !