We love the new Hayward H100ID1 natural-gas heater, but it seems to make a lot of noise, and after about two weeks it hasn't gone away. I can't tell if it sounds more like a whiny, squeaky fan bearing or if it's associated with the boiler/burner process, but it doesn't sound right. Should I be worried about this or does everyone's heater sound like this and I should just live with it?