Fill your fresh water tank with a water and bleach solution and then run it through all your faucets. Shut off the water and let it sit over night. The next day, flush your tank and lines several times until there is no more bleach smell. Run it through the ice maker if you have one and be sure to remove and replace any built in filter you might have. Run it through the hot water tank also, and flush the hot water tank using a flushing wand through the tank drain to remove any sediment. This should cure the rotten egg smell.