You can expect a new water heater to last from 8 to 12 years, depending on the unit, maintenance schedule and local weather conditions. Regular maintenance can increase the lifespan of most water heaters.
To keep your water heater functioning longer, drain it twice annually to remove the collected sediment and keep it at a temperature of 120 degrees Fahrenheit to avoid overheating. If you notice your water heater is leaking or working erratically, call an expert to look at the unit. In some cases, the problem is solvable by fixing an electrical problem, like a blown fuse or a defective heating element.