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Can you vent a hot water heater out the wall.
All solid liquid or gas fueled water heater whether they are tank type or tankless must vent through the roof unless they are direct vent.
A blower or power vent draws combustion air in to the heater and a power vent pushes exhaust gases out through a separate or dedicated exhaust flue.
Can a standard water heater be side vented.
Exhaust gases are vented outdoors through a separate vent duct or through a separate chamber of the same pipe this requires a double wall vent duct.
Most tank type gas water heaters are atmospheric vent type and they are required to vent vertically and above the roof of a home.
Exceptions may be made for non combustible walls such as solid masonry.
To make venting easiest install your tankless water heater on an outside wall.
If the unit is installed on a basement wall the vent pipe can be run up just a few feet and then vented out the side with the use of a 90 degree elbow.
They are a bit more expensive but do not require electricity to run a power vent.
Water heaters and vents come in multiple forms including induced draft direct venting and conventional draft.
With a direct vent system air for combustion is drawn from a vent pipe that runs through an exterior wall or the roof.
Installing your tankless water heater for easier venting.
This one vents out the side wall and it is perfectly fine.
Yes you can vent a gas fired water heater out of the wall if it is either a power vent unit.
The difference is that a power vent water heater pulls in combustion air from the space.
Without knowing the water heater type vent type location and type of termination no one can give you a more definitive response.
Single wall vent pipe cannot pass through any interior wall.
Direct vent water heaters.
The only other option is an electric water heater which requires no vent.
They do make two models of power vent units one is called a direct vent power vent as bob harper pointed out it draws its combustion air from outside unlike a standard power vent unit which burns its combustion air from the dwelling.
If your water heater is near an outside wall you can go with a direct vent water heater.
The heating appliance vents directly out through a building side wall powered by natural draft provided by the heating equipment typically using a single wall metal flue or chimney or a b vent.