Are you familiar with it?
Let’s describe it here. Power
vent heaters have a fan that blows exhaust gases out of the vent pipe. Where and when would they be the preferred
type? Generally, they are used when the
heater location is far inside a building and long, possibly horizontal vent
runs are needed.
Basically, the difference between a power vent and direct
vent power heater is that the power vent one removes combustion gases from the
atmosphere via a powered venting fan while a direct vent moves these gases into
the outdoor atmosphere using a chimney or exhaust pipe. They are generally more expensive than simple
water heaters.