The difference is that a power vent.
What is a power vent natural gas water heater.
Smith power vent gas water heaters are equipped with an electric blower fan that is installed on top of the water heater which requires an electrical outlet to be close to the water heater.
That is the average water heater still burns fuel be it natural gas oil or propane and that fuel burning releases byproducts like carbon monoxide.
Do not common vent a natural draft gas fueled water heater with any power vented appliance.
This will need a 120v power supply next to the tank.
Although the water heater is fuelled by gas the power vent will require an electrical connection.
In fact you will hardly notice it while in use.
Do not share a power vented appliance flue.
A direct vent system typically results in lower water heating costs because the exhaust gases are vented vertically with no extra power required as is the case with the power vent water heater.
All water heaters that burn natural gas or liquid propane lp gas require a venting system.
Power vent sharing common venting.
Fortunately the blower on this product is much quieter than most other power vent heaters.
The sketches below adapted from the whirlpool installation guide we have cited are examples of vent pipe system installations and may or may not be suitable for your.
Direct vent water heater when using a direct vent water heater water is heated by the heat of fuel combustion.