Mine has always been loud enough to hear its burning since its been new. Not annoyingly loud but I know its on. On a nice warm night with the windows open I can see it being loud enough to be heard by my neighbors given the proximity in some parks so I only heat with propane initially to get things hot and I shut it off and go electric when we are plugged in. I can have hot water for many hours even when everything is shut off. I only heat things up again for showers. Yours is most likely just fine but I would check the flame just in case.