In alt.home.repair, on Thu, 17 Jan 2019 08:29:47 -0800 (PST),
wrote:

Did this work? I have this same problem. If I am home I can clean the vent off with my hands but if not home it stays clogged/covered in frost/snow...

I still don't understand why people on Usenet neither see the previous
posts that explain the problem, nor does the post we do see bother to
quote what the previous poster said was the problem.

So we don't know what "this" is in "Did this work?"
--
Micky

https://youtu.be/CDjT1fhrs-A