Hardly and barely are negative words and should not be used with not or other negatives: I can\'t hardly believe it.
Hardly can be used to mean \'almost never\', but barely is not used in this way: She hardly (ever) sees her parents these days. * She barely sees her parents these days.
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barely {speaker}, AmE {speaker} adverb
1 in a way that is just possible but only with difficulty:
He could barely read and write. * The music was barely audible. * She was barely able to stand. * We barely had time to catch the train.
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Jak podaje slownik Oxford advanced Genie ( jest swietny) Slowo barely oznacza , ze cos jest mozliwe, ale with difficulty ( czyli ogrzewanie jest, ale bardzo \"kiepskie\", prawie niewyczuwalne, ale jest!!, natomiast hardly: used to suggest that sth is unlikely or unreasonable, almost no. z KONTEKSTU ZDANIA WNIOSKUJEMY O KIEPSKIM OGRZEWANIU, A NIE O JEGO BRAKU I DLATEGO SLOWKO BARELY IDEALNIE PASUJE, SLOWKO HARDLY MA WIECEJ ZNACZEN....NIE WIEM, CZY POMOGLAM, ALE JA TAK TO ROZUMIEM.