Condensation management techniques for a gas flow delivery system. The techniques include providing a radiant barrier associated with patient circuit and/or a patient interface, providing a water trap and/or an absorbent insert in the patient interface device, or a combination of these techniques. The radiant barrier prevents condensation from forming in the patient circuit and/or the patient interface. The water trap and absorbent insert in the patient interface control condensation that reaches or forms in the interior of the patient interface to prevent it from interfering the user of the gas delivery system.