GeorgK had some mistakes in formulas

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Looks like https://github.com/Gazz-yniere/MQ135 fork is more correct one.

Original post has many of corrections and WTFs, but author gone nowhere.

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One of known issues: GeorgK/MQ135#2 by lorf

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Ok, as I see lorf’s patch had applied.

Are you know, is it enough?
Does sensor work relatively good in comparison with more advanced ones?

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Gazz-yniere as I see now uses incorrect formula, but has good part: request methods for other gazes except CO2