I have a new house (Oct 2020, am first occupant) and a new LG dryer (bought it when I moved in). The duct runs to the outside a few feet away, where there's a screen and a flap (lift the flap and there's a screen covering the termination of the duct). Lint constantly accumulates on the inside of that screen and needs to be cleaned out; we find this out when the dryer registers an airflow error and stops drying effectively. I've cleaned the duct and screen three times and had it done professionally once, all in the 8 months we've lived here.
We had an LG support tech come look at the dryer and he just insists we need to clean it, and basically didn't believe us when we said we'd done that only a month before. He also suggested it was a problem with the duct, but I don't get that either: the duct's job is transport air to the outside; it's doing that effectively, but the screen is full of lint because the lint can't pass through it. It can't be the case that things are functioning right.
My theory is that something is wrong with the dryer that's causing lint not to get caught in the lint trap and instead get pumped in large quantities through the duct, which of course accumulate at the screen. Is that right? And if so, what are the troubleshoot steps?