“Water expansion tanks are defective.”
The Kenmore water heater expansion tank only has a 30 day warranty. Becareful, our unit rusted from the inside and created a hole in tank which sprayed and flooded our basement. The unit was installed with our new water heater one year ago. Though the water heater was covered under a one year warranty the expansion tank is not. The other disappointment is Sears can not replace the expansion tank, so don't bother calling them. If you ask Sears repairs and service to come out, they will hit you with a service bill and inform you that a licensed plumber has to replace the unit. The Sears repairman that visit our home narrowed it down to "Your expansion tank is defective, but no longer covered under warranty".