The answer often depends upon where the water heater is located within the home and it’s age. Average life expectancy is typically somewhere in the 8 -10 year range but we find 20 + year old units here in New Jersey that are still working without incident.
Your tolerance for the risk of a sudden failure and subsequent water damage play into whether you proactively replace the water heater that has been identified as beyond it’s normal life expectancy or whether you monitor it closely for any signs of future leakage and replace it at that time.
If it is located in a finished area of the house or basement then the safe approach is always to go ahead and replace it.
A simple but effective battery operated water alarm placed on the floor next to your water heater can sense the earliest signs of leakage and prevent costly water damage. A metal containment pan beneath it with a drain pipe will be effective in preventing water damage also.
Eastern Home Inspections (800) 333-2783