dolezsa / thermal_comfort

Thermal Comfort sensor for HA (absolute humidity, heat index, dew point, thermal perception)
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Wrong implementation of heat index: stair steps around HI = 26.1 C. #341

Open darrenfreeman opened 6 months ago

darrenfreeman commented 6 months ago

I am seeing stair-step glitches in the heat_index sensor, for example with 72% humidity, and temperature going from 25.5 C to 25.7 C. The resulting heat_index jumps drastically.

See the attached chart, with heat_index crossing my temperature setpoint unreasonably often - it happens to be 26.5 C.

The implementation differs significantly from the formula given in the source material from NOAA, and it can easily explain this issue. I am testing a solution, and will create a PR in the next day or two.

2023-12-13-heat-index-glitches