Panasonic ERV cold weather issue. – GreenBuildingAdvisor

Not long ago I installed a Panasonic Intelli-Balance 100 in my basement. It is a stand alone setup. It does not tap into the current hvac at all. I used the Panasonic FV-WC04VE1 exterior vent cap. It’s styrofoam that splits in two and has exhaust on one side and inlet on the other. The system has been great through summer and fall. The air quality is much better. But as soon as the temperatures started dropping below freezing the duct that brings fresh air from outside has had a lot of condensation. I did exactly as the directions said and used insulated flexible ductwork attached to the ERV and the styrofoam pipe. I taped it with foil tape. I live in Pennsylvania so the cold temperatures are just starting. I know I had it sealed good because I noticed the insulation looked more puffy than the exhaust side. So I undid the tape and water poured out of the insulation. It wasn’t just damp it was completely soaked. But the tape held all the water in. None leaked out until I pulled the tape. The exhaust side was perfectly dry. Also the styrofoam was dry. Just the flexible insulated part was soaked. Also the inside of the ERV was completely dry. So I used new insulated duct and made sure to tape it good. It went down to 25 degrees last night and I checked this morning and the insulation was soaked. The ducts leading from ERV to the outside are only about 3 feet long and go pretty straight so I don’t have much insulated duct to worry about. I did exactly what the directions say. What else can I do to stop the condensation? The unit doesn’t have a condensation drain but it is intended to use in the cold weather. Also the basement is currently 68 degrees and 40 percent humidity.