The reason is because like a standard water heater they create dangerous combustion gases when they fire.
Tankless gas water heater venting.
Concentric vents provide a couple of advantages.
Venting for gas tankless water heaters.
If you have a gas fueled tankless water heater that is installed inside the house it needs to be vented to the outside.
Indoor tankless water heaters use either steel venting or pvc venting depending on the model you purchase.
However it doesn t have to be an expensive hassle to vent.
Traditional gas tank water heater require venting through the roof.
Tankless water heaters can be vented in two ways.
Power vent units use indoor air for combustion and simply vent the exhaust to the outside.
Direct vent water heaters can use two separate pipes for intake and exhaust but some manufacturers offer concentric venting a single pipe that contains an inner exhaust vent and an outer intake vent.
View as grid list.
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.
Direct vent units pull in air from outside the house so they have two vents for intake and exhaust.
Tankless water heaters use fans to blow exhaust from the unit horizontally allowing vents to terminate on the side of a house.
The gases contain carbon monoxide.
See the use and care manual for important information regarding the venting installation and materials for your tankless water heater.
But if you have an outdoor unit then you don t need a vent as the exhaust is already outside.
Tankless water heaters don t always need two ventilation pipes even for direct vent units.
If you have questions just call tanklessking today for help.
Tankless water heaters are ventilated in two ways.
Tankless water heaters can vent through the roof or a side wall creating more flexibility and options for placement.
It doesn t matter if the gas is natural gas or propane this fact remains the same.
All indoor tankless gas water heaters must be vented vertically or horizontally to the outdoors using factory approved venting material no other venting material is permitted.