Hey all,
I have a navien Water heater integrated through hacs. I built a custom sensor in my config file that basically converts a sensor from the integration from ft3 to gallons (screenshot)
From there I set out to track daily and monthly use that should reset on those intervals and hopefully be available in a graph. But utility meter is not tracking correctly and keeps adding to ‘total gallons’ to the delta as seen in the screenshot. It’s difficult to explain. But daily should be 0.10 right now. Instead it’s totalGallons + 0.10.
The odd part is it works for a day then does this
To have a good state of utility meter, you should have a source sensor with total increasing and set your reset on utility meter daily. Every night, your utility meter sensor will go to zero and save the current value of source sensor and throughout the day, it will increase while source is increasing.
If your source is not total increasing, it is a different story 
Thanks for the reply. My Total gas sensor does math on a sensor that IS total increasing. The integration has a total increasing sensor called ‘cumulative gas’ and it’s measured in ft3v(incorrectly). So my sensor just takes that value and divides by 39. Wouldn’t that inherently make it Total increasing also?
Check Developer Tools → States page.
If it is missing, you can customize it like (Customizing entities - Home Assistant);
sensor.bwt_water_treated_total:
state_class: total_increasing
I’ll make this change and report back. I’m going see about purging the bad history
