Direct Vent Water Heater Venting Requirements

The venting must be vertical or upward sloping so that the hot exhaust rises up through the venting to exit your home.

Direct vent water heater venting requirements.

18 minimum from the ground and 12 from ceiling overhangs. This venting may either be dedicated to the water heater or can be shared with other atmospheric vent appliances such as a furnace. Atmospheric venting works on the principle of hot air rising. Never operate the water heater unless it is vented to the out doors and has adequate air supply to avoid risks of improper operation explosion or asphyxiation.

See figures 4 through 8 and items below. In direct vent applications this clearance distance must be in compliance with local building codes the requirements of the fuel gas supplier for the heating appliance in use and the appliance manufacturer s instructions. As you can read in our citation of direct vent and sidewall vent clearance distance requirements in the faqs below the outlet inlet of the vent and air intake terminations shall be a minimum of 12 inches above highest anticipated snow level. When determining the installation location for a direct vent water heater snow accumulation and drifting should be considered in areas where applicable.

The vent outlet must be installed a minimum of 12 in. The natural gas fueled water heater shown at page top is improperly vented lacking the recommended minimum 12 of vertical rise before the elbow and vented directly into a large masonry flue where it cannot develop adequate draft. Above the air intake inlet. Vent adapter is needed to connect the water heater which is tankless to the exhaust hose.

For this reason common venting configurations are no longer allowed in some code jurisdictions where direct venting or power venting of water heaters is now mandatory. For non direct vent applications that is side wall venting only the required clearance is 7 feet. This difference in operation means that you can install a direct vent system almost anywhere. A direct vent system pulls in air from outside and then vents the exhaust through a horizontal pipe.

Warning vent termination must not be within 4 feet of any items such as gas meters gas valves or other gas regulating equipment. 18 minimum in all directions from any obstruction that may interfere. The water heater must be properly vented to the outdoors. All emission of liquid or gas water heaters which are tankless needs vent pipes made of stainless steel and approved by ul.

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.