LevitonIPHS5-1LW Decora In-Wall Humidity Sensor & Fan Control , 3A, Single Pole, White

So, I'm a pretty smart guy (I think). I've rewired my own house before, and since it didn't burn down or blow up I'm sure I did a good job (the inspector even said so). This switch threw me. Why? Because this NEW house I'm in doesn't have a neutral wire available to the switch. Unbeknownst to me, the neutrals were all wired together in a bundle in the back of the switch box. SO...if the switch you're replacing is also only wired with a load and line, look for your neutral bundle in the back of the box. Once I tied in an 8" neutral to the bundle and wired this guy up - the switch worked like a rock star.Currently have it installed in my laundry room, and it comes on almost immediately after we start a load of laundry or use the utility stink. The laundry room even smells better since pulling the humidity out prevents mildew and keeps the room from having that damp smell.When the humidity in the house increased when it was raining outside, the switch activated and helped pull humidity out.I'm ordering two more for my bathrooms. With my "tight" house (full spray foam insulation) only able to pull moisture out when the HVAC system is running, these humidity switches do a great job moving air through the house and helping that system out.

My family and I are paranoid about a poorly-ventilated bathroom, so we religiously run the exhaust fan during and after showers. With busy lives and kids to take care of, this often means walking away from the bathroom right after a shower, with the fan still running.On weekends I would occasionally come upstairs mid-afternoon to find the fan running from a morning shower. Some evenings I would come home from work and find that the fan had been running all day. In a previous home I installed a digital fan timer to remedy this problem. However, a moisture-sensing fan switch is a more elegant and appropriate solution. It also costs about the same as a digital timer, and the labels on my old timer wore off after a year or two. I have had this moisture-sensing switch installed for a few days, and without fail it turns on during a shower event. In some cases it comes on mid-shower, in some cases it comes on AFTER the shower is turned off, and in at least one case it has turned on post-shower, turned off, and then turned back on again. This gives me the confidence that the humidity sensor is working and is responding well to changing conditions. It's nice to be able to walk away from the bathroom after a shower and know that your home is being taken care of.This device does require a neutral connection as well as the typical hot, load, and ground. For me this wasn't a problem, but if the power comes in at your fan and not at your switch box, and your switch box has only a switch leg, this device won't work for you.

I studied up on the available humidity switches and decided on Leviton based on the features and price. I'm happy with my purchase.1. The timer is great, which can be set at 10 min, 20 min, 30 min and 45 min. The fan will run for that set time and turn off, or you can still manually turn off any time.2. The humidity set point can be set for Off or any range between 20-80% humidity, and also an Air Cycle mode. When using Off it'll ignore the humidity set point and run when it detects excess humidity. I'm not sure if that means it'll detect an average of the current humidity level and only turn on if it increases above that average. I set mine at about 40%. Air Cycle will run the fan for the timer duration once every hour, nice if you need constant air flow regardless of humidity.3. The sensitivity levels. Off, Lo, Med and Hi. Off is for Air Cycle mode only since it runs based on the timer not the humidity. Lo Med and Hi sensitivity levels have two uses each. Lo is for small spaces but also the least sensitivity, and so on for Med and Hi.My bathroom is about 6 ft x 6 ft. I have my timer set for 10 min, humidity at about 40% and sensitivity on Lo. I live in Colorado so our humidity inside is usually around 30%. So far this setup is working perfectly, I turn the shower on and within about 2 minutes the fan turns on, then turns off about the time I get out. It might turn itself back on again if there's still too much humidity then shut off after another 10 mins. I have not had this randomly turn the fan on when not using the shower. This is exactly what I wanted to prevent mold and prevent manually touching a switch.My fan and light are separate units but this switch can also be wired to a fan/light combo. Only problem there would be using the timer since it would also turn the light off. Regardless of that, you will need a neutral wire (usually white sheathed) for electricity return. This switch will not operate correctly without a neutral wire, it'll remain on all the time without it because the power has nowhere to return to. Most switches these days need neutral which is a good thing for safety. If your house was built in the 90s and newer, then you should have neutral wire capped in your switch boxes even if your current switch doesn't use it. It's easy to add a connection to that with more 14 gauge copper wire.Edit: I changed the sensitivity level to Med. There's a vent directly below the switch and noticed on Lo the switch wouldn't activate if my furnace blower fan was running.Update, a few weeks later: Now the switch won't turn on the fan regardless of the humidity settings. My wife said it still works for her but she didn't even want this switch. So I'm dropping my rating on this from 5 star to 3 star because it was for me and my peace of mind. At least the timer still works well.Update, another few weeks later: Since my last update its been working well so I'm changing my review from 3 to 4 star. I won't take it back to 5 star, just in case.