Use heat-trap valves in water heaters
Valves prevent heat loss due to thermosiphoning.
Because hot water is lighter than cold water, there is a tendency for hot water in the storage tank to migrate into the supply lines where it cools off and drops back into the tank. This cycle, called thermosiphoning, significantly increases standby heat losses but can be prevented with the use of a heat-trap valve.
Learn more in the Green Building Encyclopedia
