Another fix for an older and even most new hot water heaters is installation of a heat trap . Some but not all of the new heaters come with traps preinstalled. Residential water heaters lose some of its heat loss while in standby up through the tank's inlet and outlet piping. A heat trap can reduce this heat loss by up to 40 percent. One type of trap, manufactured by Bradford Whit, is available for both inlet and outlet fittings. It incorporates a flexible disk that helps keep heat from floating...