Tankless Water Heater Vent Pipe Size

A power vent has the intake on the actual body of the tankless heater and not through a pipe or vent.

Tankless water heater vent pipe size.

Concentric vents also offer a safety benefit too. In fact tankless water heaters save up to 16 square feet of space. Here are a few things your installer should consider for effective tankless water heater venting. Examples include a direct vent and tankless water heaters.

The existing vent system must be ul listed type b double wall or single wall metal vent pipe of either 3 inch or 4 inch diameter and installed according to the vent manufacturer s instructions and the terms of its listing. Outside tankless water heaters free up indoor space. Power vent units only require an exhaust vent and must be placed in a larger area for adequate air quantity for combustion. This configuration allows tankless units to fit in smaller spaces.

All emission of liquid or gas water heaters which are tankless needs vent pipes made of stainless steel and approved by ul. Concentric vent terminations are usable on power direct vent tanks or tankless water heaters to enjoy the same benefits as single wall and roof penetration with an. So while concentric vents are larger typically 5 inches in diameter vs. Vent to the outside.

3 inches for a single pipe they don t require additional clearance through the wall. Concentric venting is usable for full vent functionality i e from your water heater to outside the house for specific models built for precisely this venting method. This takes in the air from the surroundings so it uses the inside air to vent with an exhaust leading out of the house. But on average a 1 2 distribution pipe is only good for about 3 fixture units while a 3 4 pipe is rated at approximately 10 fixture units.

Do not use other materials such as dryer vent hose. Select either an adapter of three inch or an adapter of four inches depending on what water heater model you decide.