Central nouns? My central nouns unit make a noise close to a fax...
My central nouns unit make a noise close to a fax machine beside out any paper. (like a small motor turning) I've never have central nouns before. Is this a commonplace noise?
Answers: The compressor will trade name a noise that sounds kinda close to a rumble. That may be what you're hearing. It will be louder than a skylight AC because it's a much larger compressor.