A Big Belching House Guest

In an area with hard water, a noisy water machine is in need of repair.

If your water heater is gas-powered, call the gas company for specific instructions before attempting to re-light it yourself. In many cities, they will come to your home and do that for you, no charge. evgeniykleymenov/Shutterstock

Our house is not haunted, but just try to tell that to our guests. “Our water heater makes funny noises,” I warn. First-timers respond with a smile and nod—and forget.

“What was that noise?” is the predictable next-morning question. Some say it sounds like a big clumsy man on the roof. Children trend more toward a “monster in the wall” theory.