A device and method is provided for automatically removing water or accumulated moisture from a breathing circuit. The device includes a housing with breathing circuit flow entry and exit ports and a water drainage port. A buoyant body in the housing can mate with a float valve seat to seal the drainage port, and is moveable to open the drainage port when sufficient liquid accumulates in the interior space. The buoyant body displaces a substantial portion of the housing inner compressible volume. Water is automatically removed by a water vapor permeable container coupled to the housing receiving flow from the drainage port, or the device is coupled to a source of suction, further including at least one bleed port fluidly coupling the source of suction to the surroundings, acting with a valve element to equalize any pressure differential between the housing interior space and suction connection, when no water is accumulated in the device.