Power and direct venting each provide an alternative to standard gravity (atmospheric) venting in gas and oil appliances. They can save space by allowing horizontal venting out a wall if properly configured. Both power vent and direct vent systems use a blower fan to force exhaust from vent pipes.
The major difference is that power vented devices get their intake combustion air from indoors, while direct vent (also known as sealed combustion) units pull it from outside. This means the power vented models must have adequate space for combustion air at the location they are installed. Direct vent units require two separate penetrations from the building (one for intake, one for exhaust), although a concentric vent kit limits both functions to a single protrusion. SupplyHouse carries a full selection of boilers and water heaters, including power and direct vent models.
