Gas tankless water heaters don t have to use indoor air for combustion.
Tankless water heater venting requirements.
Tankless water heaters are vented in two ways.
Outside tankless water heaters free up indoor space.
The attached installation instructions from the manufacturer of these water heaters require a minimum vertical rise in the water heater exhaust flue as well as a proper ul listed chimney cap or termination for safe venting of combustion products.
Indoor tankless water heaters draw in outside air.
Tankless water heaters don t always need two ventilation pipes even for direct vent units.
Select either an adapter of three inch or an adapter of four inches depending on what water heater model you decide.
No they don t need to be vented.
Tankless water heaters can be vented in two ways.
There are grave liabilities and risks involved in violating basic mechanical and safety standards.
Direct vent and power vent.
If you have issues with where to place a tankless water heater due to venting concerns then your best bet may be to get an electric tankless water heater.
Facts about tankless water heater venting.
Tankless water heater venting features.
Tankless water heaters should not be installed near dryer vents or intake air vents.
See the use and care manual for important information regarding the venting installation and materials for your tankless water heater.
American tankless water heaters venting.
The water heater must be vented in accordance with the section venting of equipment of the latest edition of the national fuel gas code.
All emission of liquid or gas water heaters which are tankless needs vent pipes made of stainless steel and approved by ul.
Ansi z223 1 nfpa 54 in the united states and or section 7 of the can csa b149 1 natural gas and propane installation code in canada as well as applicable local building codes.
The tankless heater cannot share vent piping with any other appliance and it cannot use a masonry chimney flue for venting.
Vent to the outside.
Any new tankless is going to require a special type of venting whether it be pvc or a proprietary brand.
The biggest issue i see with tankless water heaters is contractors using the existing 3 4 gas line.
Vent adapter is needed to connect the water heater which is tankless to the exhaust hose.
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.
You do have way more options with electric than with gas or propane but the issue generally is the gpm.
Tankless water heater vent clearances if the unit is vented to the outside then it needs 12 inches of clearance from a door or window.
Tankless units withstand below freezing temperatures.
The high efficiency 90 or higher furnace will also require pvc venting.