GSW ENERGY STAR® Power Vent gas water heaters have been engineered to provide the highest energy efficiency ratings for a water heater of its kind. A Power Vent heater is used when conventional chimney venting is not an option. Air is drawn from inside the home while a rotatable motorized blower forces the exhaust outside. The GSW ENERGY STAR® Qualified Power Vent heater is a very energy efficient heater which saves you money on energy costs and it's more environmentally friendly. This 41 gallon water heater features factory-installed heat traps on the water inlet and outlet to reduce the amount of heat lost through piping, improving energy efficiency; exclusive TankSaver® design prolongs tank life; robust air intake snorkel inhibits flammable vapours from entering the combustion chamber; sensor detects flammable vapours and automatically disables the unit to prevent their ignition; state-of-the-art electronic gas control featuring advanced self-diagnostic capability that makes troubleshooting easy; and flexible venting options: it can be vented with 2", 3" or 4" ULC S636 PVC, CPVC or polypropylene pipe up to 180 equivalent feet. This unit is ideal as a replacement water heater in a variety of applications due its 3-position rotatable blower.