Tankless water heaters use fans to blow exhaust from the unit horizontally allowing vents to terminate on the side of a house.
Water heater roof venting requirements.
The first permit is for the water heater itself.
Gas tankless water heaters don t have to use indoor air for combustion.
The water heater s vent pipe must be the same size as its draft hood.
The most common problem associated with water heater venting is a condition called backdrafting in which exhaust gases from the water heater fail to exit the home via the vent and instead end up in the house backdrafting can have many causes but it is most commonly due to poor vent design or installation and or an imbalance of air volume in the home.
Atmospheric venting refers to a system in which exhaust from the water heater naturally rises out of the appliance s combustion chamber then travels up through a standard chimney style flue.
Illustrations of proper gas fired water heater venting using type b double wall vent pipe through a roof above or through a chimney below include details for the flue vent connector such as the requirement of a minimum vent connector upwards slope of 1 4 per foot of horizontal run.
Tankless water heaters can vent through the roof or a side wall creating more flexibility and options for placement.
In almost all circumstances replacing an existing water heater will require either one or two permits.
Tankless water heaters provide either horizontal venting or vertical venting which is also referred to as tankless water heater venting through roof.
The gas heater vents out the side of the house so the water heater is the only item venting through the chimney.
This will allow your water heater to operate efficiently and effectively and most significantly it will avoid any probability of danger and therefore the risk of carbon monoxide gas poisoning.
Needs pvc or category iii stainless steel anything else faces severe corrosion that will end up shortening the lifespan of your tankless will cost money to replace masonry of your chimney and can.
Before you decide against a tankless water heater for your next project consider these tankless water heater venting requirements.
Traditional gas tank water heater require venting through the roof.
This is as easy as heading down to the local planning or building department to ask for one.
The size in gallons of the water heater.
Tankless water heaters can be vented in two ways.
Proper venting prevents backdrafting.
The maximum dimension of the water heater venting only vent pipe is determined by.
A few rare cases may also require a third permit.
The chimney above the roof is in very poor condition.
Here s my question can i disassemble the chimney to just below the roof boards and vent the water heater a few feet above the roof material using a liner of some sort.
Shouldn t share venting your tankless water heater needs to have its own vent and cannot share one with a furnace or other water heaters.