When to repair
Many people get to the crossroads on whether to repair or replace their water heater. This can be a tough decision. If you kept up with maintenance as lined out in your owner’s manual, it will make more sense to repair an older water heater. If it is under full labor, tank and parts warranty go ahead and have it fixed. At the time of repair, make sure you ask your plumbing technician if everything was installed correctly. Most parts’ failure are due to improper installation. If there are any installation faults, have them fixed so you don’t have the same problem again. There are major upgrades in water heaters every few years. Some upgrades come from research and development, mandates pushed by the US government and others from lessons learned from previous water heater failures. If you bought the first batch of a new series which has recently been updated, it is recommended that you get newer updated unit of the same series.
When to replace
Anything over 8 years old should be replaced. Especially if you did not keep up with maintenance, trying to repair it would only be putting a Band-Aid on an artery. The money saved on energy bills will offset the cost of installing a new one. Water heater companies want to sell water heaters not parts which can cause the parts to be costly. If they still use the parts today, it may be ok to get and install that part. If it is a part they no longer use, it will come at a premium price.