Radon mitigation equipment?

I ran across this fan in the attic of a house and wonder if it might be the remains of a removed Radon system. Have included photos of the route to the basement thru a hall closet where there is a loop of tubing also that terminates down in the basement next to the larger pipe that has been cut off in the basement photo.
Not a single label left on the electrical panel, 38 year old house with many “home owner modifications” than forclosed with stuff removed. Some abandoned wiring and controls labeled “pool & Spa” in the basement, not too far from the pipe but no indications in the attic at this spot of condensation like one would expect if this was a exhaust fan from maybe a hot tub down there. Possibly a Meth Lab?
Any ideas guys?

It’s a mystery Gary but it does not look like any Radon system I have seen.

Write it up as unknown with a recommendation to consult the owner for an explanation.

Thanks Michael:
I haven’t seen any systems as we don’t seem to run into much Radon around here but I thought I would throw it out just in case I was overlooking the obviuos and should recomend testing (which maybe I will anyway as a CYA).

BTW Gary… even if it is a Radon mitigation system, and even if you can hear it operating, you would always want to recommend Radon testing to verify the mitigation system is actually doing it’s job. JMHO.