Direct vent units attract outside air from the house or building while power vent units solely need an exhaust vent and should be installed in a larger area for receiving sufficient air amount for combustion.
Tankless hot water heater exhaust.
How water is heated in a tankless water heater when you turn on your hot water tap it begins to pull water through the intake pipe.
Direct vent units pull in air from the outside so they have two vents for intake and exhaust.
The exhaust is a gas condensate that is highly acidic and corrosive to the venting so they require the right material.
Tankless water heaters with condensing technology are up to 95 more efficient than non condensing units and emit a comparatively cooler exhaust gas according to the propane education and research council.
Power vent and direct vent.
Tankless water heaters can be vented in two ways.
A flow sensor in this pipe then signals the control panel to begin the heating process.
Power vent units use indoor air for combustion and simply vent the exhaust to the outside.
The exhaust vent can therefore be pvc or polypropylene and not metal a feature that lowers.
Power vent units use indoor air for combustion and simply vent the exhaust to the outside.
Condensing tankless water heaters lower the cost of installation.
Tankless water heaters use fans to blow exhaust from the unit horizontally allowing vents to terminate on the side of a house.
Tankless water heaters are ventilated in two ways.
All of them unpleasant and some quite dangerous.
Direct vent units pull in air from outside the house so they have two vents for intake and exhaust.