Most experts agree that you should have your water heater inspected at least once a year, but some may say every six months. By having it inspected regularly, you can catch any potential problems before they become too serious.If your water heater is older, say ten years or more, then you should have it inspected more often, perhaps every three to six months. Age is not the only factor that determines how often you should have your water heater inspected; if it has been damaged or there is some other problem with it, then you will need to have it checked more often.There are a few things that you can do to help extend the life of your water heater, and having it inspected regularly is one of them. Making sure that the temperature setting is not too high and that there is enough insulation around the tank can also help.