I've got a bathroom exhaust fan, well automated via RM and the humidity value reported by an Iris V3 motion detector. However, the fan is a bit noisy and doesn't move enough air.
The current fan is a cheapo (contractor grade) Nutone-Broan model, probably 50CFM and $16.97 from Home Depot. There's about 25' of single-wall dryer exhaust hose passing through an unheated attic between the fan and where the air exits at the roof soffit.
I'm considering installing either a higher capacity (150~200CFM) fan -- requiring a slightly larger hole in an inconvenient location or a "booster" fan that goes in-line with the duct. The booster fan is triggered by a pressure switch, sensing that the primary fan (controlled by HE) is on, so the booster doesn't need any smart home automation.
I've got 4 of the basic Broan models in my home. I never really noticed how noisy they were until we finished our basement and the contractor installed a "better" model. I think it's a Panasonic. Much quieter and seems to move decent air. Although seems like it could be a lot of work to replace an existing unit.
If you've got the space to install a booster, could you just gut the Broan and install a good inline unit as the main fan?
I have a Panasonic 80 CFM in a small bathroom (with a shower). The fan is a centrifugal with very small blades. A combination of dust and moisture causes the dust to collect and stick on the blades, reducing its capability. Just a thought to consider.
I'd second the suggestion for Panasonic if you can replace the existing fan. Was in the same position some years back with cheap noisy Broan bathroom fans - replaced with Panasonic when I remodeled, they seem infinitely better.
25ft of dryer hose also sounds like a lot - could you replace that with rigid metal duct where it runs through the attic? That would reduce the back-pressure by quite a bit, as flexible duct just doesn't flow well.
