Review on 🔆 TOPGREENER TDHS5-N Humidity Sensor Switch: Automated Control for Bathroom Fan, Adjustable Timing, UL Listed - White by Lild Zimmerly

I think the main disadvantage of this type of device is that the warm, humid air created by the hot shower rises to the ceiling where the sensor is located in the device. can't see it. So the sensor registers a modest increase in humidity as warm, moist air erodes your ceiling and/or deposits moisture in your attic. For example, to test, I took a hot shower for about 15 minutes a day when the ambient humidity was about 65%, which is too high for the "medium" setting of 45-50%, so I used the "high" setting, which starts at 85%. I placed another humidity sensor next to this device, and the test sensor only registered a few percent increase in humidity during the shower. The humidity reading gradually increased a few more percent for some time *after* I turned off the shower, likely because the humid air had cooled and dropped to the level of the test sensor (and this device). The fan never came on, although I'm sure it produced plenty of humid air. So ok the humidity sensor isn't that useful but you can manually start the fan with a switch which should help. However, this device has a fixed standby time of 20 minutes, which is shorter than I find adequate. If you want to use a humidity-controlled fan, I would suggest a fan with a built-in humidity sensor, which I assume is much more sensitive to humidity if it builds up near the ceiling. After living with this device for a while, I relented and gave it an extra star. My daughter takes incredibly long hot showers, in which case the sensor eventually turns on the fan and helps get rid of most of the condensation. We would have preferred her showers to be shorter, but that's another story.