Gas Water Heater Venting Options

The main problem with atmospheric vent systems is that they are susceptible to back drafts more on that later.

Gas water heater venting options.

Type b due to its temperature rating can only be used with atmospheric gas water heaters. Type l is stainless lined and used for oil and power gas heaters. The difference is that a power vent water heater pulls in combustion air from the space around the appliance then uses a fan to propel the exhaust through the vent. A direct vent system pulls in.

Power vented water heaters work the same as ordinary water heaters but the exhaust gases are blown out with a small fan instead of rising upwards through metal pipes. Tankless water heaters can vent through the roof or a side wall creating more flexibility and options for placement. A concentric vent kit has both the intake and the outgoing in the same pipe. Atmospheric gas water heaters vent their exhaust through a vertical or upward sloping metal duct vent to exit the home.

The two pipe system. There are concentric and dual. Tankless water heaters use fans to blow exhaust from the unit horizontally allowing vents to terminate on the side of a house. This venting may either be dedicated to the water heater or can be shared with other atmospheric vent appliances such as a furnace.

With a replacement high efficiency furnace the existing vent pipe does not work for water heater only because the vent is too large. There are three the most used venting systems in residential water heating. The photo below shows typical combined furnace water heater venting. When installed correctly this venting arrangement works with an 80 gas furnace or lower than 80 gas water heater.

The venting system of the gas water heaters might consist of one or two pipes. Type l vent is double walled vent. Traditional gas tank water heater require venting through the roof. All water heater venting systems use a vent duct or pipe also called a chimney or flue to bring exhaust gases from the water heater to the outdoors.

Selecting the best venting option for a gas water heater types of the venting systems. The duct may be metal or plastic depending on the type of vent system. Standard atmospheric water heaters are the most common type of residential gas water heaters. All venting installations must conform with local codes.

The exhaust is in the center so that the outside of the vent does not heat up. Water heater ducts may lead directly outdoors or they may tie into a larger vent duct that also serves a gas or propane furnace or boiler in the home.