US Patent 11885493 Flue damper with a drainage port

A flue damper may include a vent pipe with a first side leading to an outlet of the flue damper and a second side leading to an inlet of the flue damper. A damper gate of the flue damper may be movable between an open state and a closed state, where in the open state, the first side of the vent pipe is in fluid communication with the second side, and where in the closed state, the damper gate interrupts fluid communication between the first side and the second side. A drainage port may also be included, and a plug may be movable relative to the drainage port to selectively seal the drainage port when the damper gate remains in the closed state.