<"She has bought a new washing machine even though her old one was working well"> Yes, It's OK. It gives the feeling that she has now disconnected, or got rid of, her old machine. I think this would be more common though: "She bought a new washing machine even though her old one was working well" "She has bought a new washing machine even though her old one is well"
New words, one handy idiom, and a 2-minute quiz — delivered to your inbox to keep your streak alive.
Marius Hancu"She has bought a new washing machine even though her old one was working well" BrEAnd if the purchase was very recent, do AE spea
"She bought a new washing machine even though her old one was working well" AmE
Both correct, IMO.