Gas water heater venting options. Similar to a furnace, water heaters with gas burners will generate harmful fumes containing carbon monoxide, a byproduct of the fuel used to ignite the burner to heat the water in the tank, whether that fuel is natural gas, oil, or propane.
Just like with your furnace, you need proper venting to ensure the safe removal of these toxic fumes.
Gas water heater venting options
Two of the most common types of vents used in residential water heaters are the power-vent and direct-vent systems.
The former kind relies on natural airflow to move the fumes outside, while the latter is an efficient system that doesn’t waste energy by using combustion exhaust gases to neutralize fumes generated by the appliance.
Flue ducts, or “stacks”, can be made of metal with either type, while other models might be equipped with stainless steel stacks allowing users to connect their water heater directly outside.
Standard atmospheric water heaters vent
Standard atmospheric water heaters are the most common type of residential gas water heaters. Atmospheric gas water heaters vent their exhaust through a vertical or upward-sloping metal duct vent to exit the home.
This venting may either be dedicated to the water heater or can be shared with other atmospheric vent appliances, such as a furnace. Atmospheric venting works on the principle of hot air rising.
Therefore, any blockages or misalignments in your home’s venting could result in excess heat and fumes being released back into the ambient air.
Studies have shown that this excess carbon dioxide can potentially increase indoor airborne concentrations, thereby presenting an increased risk to human health.
It is strongly recommended that you consult a professional plumbing contractor for installation, especially if your current system is not working properly due to age, neglect, or damage.
Direct vent gas water heaters
Direct vent gas water heaters are a type of gas water heater best suited for use when there is insufficient ventilation within the installation space in your home.
A direct vent water heater draws air for combustion from outside your home rather than inside.
The exhaust gases and excess heat produced by your water heater are then vented back outdoors.
Manufactured by ValTec, this product uses special coaxial venting that has separate chambers for intake air and exhaust in a single assembled vent piece.
It can be installed using standard piping materials, making it easy to transport hot or cold liquids throughout your home, allowing you to utilize hot or cold liquids as needed.
This feature can help minimize safety risks when installing and using a gas or liquid propane tank water heater like this one. Please consult a professional plumbing contractor when installing them.
Power Direct vent gas water heaters
Power direct venting is used when the space in which you are installing a water heater lacks sufficient air for combustion.
The idea is that ducting air from outside your house into the water heater, will help the combustion process. Similar to power venting.
It also uses a blower to channel heated gases from the water heater and vents them back outside of your house.
It’s important to note that this model requires an electrical outlet nearby (similar to power-vented units).
Power vent gas water heaters
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.
The blower pushes the exhaust and excess heat through the exhaust venting. The venting can run either vertically or horizontally with a longer line to help with space and sizing issues within your home.
Power vents are more efficient than standard atmospheric gases: these units are designed to utilize heat from the exhaust (which runs at a lower temperature) to heat water for energy savings.
Thanks to their lower emissions, they also allow for plumbing piping made from PVC rather than stainless steel. We recommend having a professional plumber install your new power-vent system.
Concentric Vent gas water heaters
A concentric venting installation is when a power vent, conventional or tankless water heater vents through a hamper that has the intake for its heating element located at the top center of the unit.
This feature gives homeowners an opportunity to mount their heater on the wall or ceiling in an area where space would have previously been inaccessible.
The entire length of exhaust piping can be contained within the same structure.
In other words, concentric venting combines both inlet and outlet pipes of a vent system in one location, as opposed to having separate openings like standard kit vents (e.g., sidewall penetrations).
Gas water heater venting options
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