What does that mean "water heater season"? The water in Chicago changes temperature dramatically from season to season. The reason is because we draw our water off of Lake Michigan, therefore the water travels through the distribution pipes at the same temperature as the lake. In the winter time the cold water at our taps can be as cold as 35 degrees. In the summer believe it or not the water temperatures can get as high as the upper 70's. These great fluctuations in cold water delivered to our water heaters puts a great deal of stress on our water heaters, and no time more than in the spring and the fall. Our tank type water heaters are made of steel and that alone is not the problem. The problem arises because the heaters have numerous welds and that is where the stress takes its toll. We are lucky here in Chicago because the average national life expectancy of a water heater is only 8-1/2 years. In Chicago we see heaters last on average 10 to 15 years. This is in part because of the quality of our water and actually because we have slightly hard water. Chicago heaters used to last even longer years ago but our water quality has changed as well as additives that are seen nowadays. So, word to the wise, know the age of your heater and if the heater is in an area of your home make sure that you either replace it proactively or have an automatic water safety valve so that in the event of a tank failure your do not damage your property.