Water Heater Roof Venting Requirements
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.
Water heater roof venting requirements. The maximum dimension of the water heater venting only vent pipe is determined by. Before you decide against a tankless water heater for your next project consider these tankless water heater venting requirements. Facts about tankless water heater venting. 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.
Proper venting prevents backdrafting. Tankless water heaters can be vented in two ways. The first permit is for the water heater itself. A few rare cases may also require a third permit.
In almost all circumstances replacing an existing water heater will require either one or two permits. Tankless water heaters use fans to blow exhaust from the unit horizontally allowing vents to terminate on the side of a house. How long the vent pipe is and 2. Tankless water heaters provide either horizontal venting or vertical venting which is also referred to as tankless water heater venting through roof.
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. 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. The water heater s vent pipe must be the same size as its draft hood. 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. 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. The gas heater vents out the side of the house so the water heater is the only item venting through the chimney. Gas tankless water heaters don t have to use indoor air for combustion.
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. Venting requirements for gas fueled water heaters. Tankless water heaters can vent through the roof or a side wall creating more flexibility and options for placement.