Product review (5 stars): Its nearly silent at low speeds
I put this in my Chevy Express extended cargo van. I cut a 14x14 hole in the roof with a jigsaw, and went to installing this vent fan. First I built a square frame with 2x2s so there was something for the fan to attach to, along with the sheet metal roof. The rest of the installation went as expected. It took some time to lay the butyl tape evenly on the corrugated van roof, but once done, the rest just drops into place. The only part of the install that I had to work over my head, was screwing in the final interior trim piece. That works for me.
Wiring was simple and straightforward, with no issues. I used a couple of wire nuts and tucked the wires under the plastic trim.
At the lowest of the four speed settings, I cannot hear the fan operating at all. Next bump up and I can begin to hear a whirring sound, but its still very quiet. Even at the highest setting, its quieter than any of the Fantastic Fans in my Squarestream trailer.
I will be replacing those old things with the MaxxFan vent fans soon!