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dolezsa / thermal_comfort

Thermal Comfort sensor for HA (absolute humidity, heat index, dew point, thermal perception)
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Your Thom Index (THI) is wrong #369

Open Percherie opened 7 months ago

Percherie commented 7 months ago

Hello,

I use the Thom (THI) to obtain a comfort index. The simplified formula is (valid for C°) THI = T - [(0.55- 0.0055 . U) . (T- 14.5)] Source : https://www.institut-numerique.org/i51-leffet-combine-de-la-temperature-et-de-lhumidite-de-lair-les-indices-thi-et-humidex-502a31728eec6

Interface for HA "Comfortable Environment Card https://github.com/argaar/comfortable-environment-card has used the work of the National Weather Service for its calculations and arrives at the same results using the complete and detailed formulae https://www.wpc.ncep.noaa.gov/html/heatindex_equation.shtml

For example, with 19.4°C and 42% U, the THI should be 17.8369 and you tell me that the index should be 15.37. "The Comfortable Environment Card gives me the right information.

I suppose there's an anomaly if we use F° or C°. Can you make a correction along these lines?

Percherie commented 2 months ago

For example, with 19.4°C and 42% U, the THI should be 17.8369 and you tell me that the index should be 15.37. "The Comfortable Environment Card gives me the right information.

I'm confused,

I came back to this ticket and I don't know how I found the numerical value of the Thom (THI) in Thermal Confort.