Our hot water heater is broken. Or rather, it sometimes is. A while ago my flatmate and I noticed that sometimes, while taking a nice hot shower, the hot water turns cold. And that sucks big time. Our heater is in the kitchen and uses natural gas. It seems like sometimes the flame just goes out. We asked a friend who fixes these things for a living and after describing the symptoms to him, he suggested we open a kitchen window while showering. The reason for the flame going out might be that there is a build-up of exhaust gases and the safety kicking in to prevent people from suffocating. Opening a window would increase the chimney effect and thus temporarily solve the problem.
Sound advice, but there is one problem: How do we know opening a window actually works, if the problem only occurs sporadically to begin with? We don’t want to end up believing in tiger repellent rocks.
The answer — of course — is: Science!