What is a characteristic of a coaxial pipe?

A characteristic of a coaxial pipe is that it combines both the air supply and the vent pipe into a single unit. This design enables the efficient transfer of combustion air while also venting exhaust gases. The inner pipe typically delivers air to the appliance, while the outer pipe is used to exhaust combustion products, creating a two-in-one system that enhances efficiency and safety.

This configuration is particularly useful in applications where space is limited, as it minimizes the number of separate pipes required for ventilation. It also helps in maintaining a balanced pressure in the system and aids in optimizing the overall performance of HVAC appliances.