Received an email stating: "We need someone to take a look at our radon mitigation system. It needs maintenance and possibly repair."
I asked for more info, and was sent these photos. I think I figured out why the system isn't working!
That looks like an early system installed in the mid 80s. I've seen a few of those in the Richmond, Virginia area. The ones I've seen are vented quite some distance away from the house, typically in the woods. There was a lot of digging and trenching involved...... We've come a long ways baby!
It was not unusual to connect to a footing drain where it day lighted in the early 90s.
Typically a PVC T was installed so the fan could be mounted vertically and a 4" check valve was installed downstream of the T. I attended certification class in 1990 that demonstrated that type of system on the field trip. The enclosure was a little more professional.