Abstract: A drain separator in a gas analyzer is provided to rapidly remove drain or condensate from a gas flow by creating a rotary motion in the gas flow prior to introducing it into a separating chamber. In an exemplary embodiment, separating chamber 2, formed as a downwardly divergent conical space, connects with gas-inlet passage 6 at its upper end and an exhaust gas-outlet passage 3 at the periphery of its base. A sample gas-outlet passage 8 is disposed within separating chamber 2 in a coaxially aligned, vertically spaced opposing relationship to gas-inlet passage 6. Rotation of the gas flow may be accomplished by a vane 7, disposed within gas-inlet passage 6. Upon introduction of the rotating gas flow into separating chamber 2, the pressure on the flow is reduced causing the drain to condense and become distributed about the circumference of the low pressure gas flow.