My hot water tank is about three years old and recently my pressure relief valve developed a steady drip. Thinking the value went bad, I replaced it but still had the same drip. I called the manufacture and the proceed to tell me its one of two things: 1. pressure relief value or 2. an increase in water pressure. I had already replaced the value so it wasn't that. I turned my main water supply into the house by half and the drip still persisted. Now they are telling me to install an expansion tank. My question to you is this, where is the optimum place to put this tank. Directly above my tank is not an option because the water supply comes directly out of the wall and into my tank. On the other side of the wall is my garage which will accomodate the size of the tank but there's probably 8 feet of water line until it goes into the hot water tank. Will this expansion tank still be as effective? If not, do I have any other options? It appears this drip developed after the cold water set in here in the Northeast. Thank you so much for your help.