Quiet Register Booster Fan Fits 4" x 12" Register Holes, 10-Speed Smart Heating Cooling AC Vent Fan with Remote Control and Thermostat Control - White

No more expensive portable room air conditioners that last less than 5 years!! These work to cool living areas: kitchen in the mornings, bedroom at night. Can't say they are 'quiet' when fan is set to high (8-10), but it's not invasive, more like airplane engine noise at cruise altitude (white noise actually puts most people to sleep, the reason so many people take a flying nap). Settings are simple to make and so far, no problem with digital panel working as expected.Important Note: these plug into electrical outlet, so carefully consider whether they can plug in near your target register vents. Elec cord is reasonably long.I've only used these for one month (summer) with central ac cooling, so can't speak to longevity, but with my bdrm door closed for an hour before bedtime, they bring temperature down abt 10 degrees (with ac running, then I turn central hvac off at bedtime, bdrm stays cool all night). Colder rooms help with getting to sleep.One more thing. These vent units measure the air temp blowing from the vent, not the room temperature. You select the vent temp -- for summer mine is set to come on when vented air is below 70; next winter over 80. Note: an issue arises when trying to set both at same time (not a flaw, issue is covered in instructions), simple to set it once per season.

My son's room is the hottest on the second floor of our house. Add his XBox running all the time and it's in the 80's consistently. This fan, which takes minute to swap out the original vent for, has made a huge difference getting the most of the cool air out of the duct and into his room. It has a remote so he can adjust the fan and it's a set-it-and-forget type thing. But best of all is the customer service with this product. When I bought it a year ago I got the wrong size. I was sent, free of charge, the right size even though it was my fault. This year, once the temps started to rise the unit fans weren't spinning. I emailed the same address I did before was sent a replacement immediately free of charge. Popped the new unit in within one minute and we were up and running again. I couldn't ask for a better customer experience and the fan makes the room cooler. Five stars.

Didn't think it would work so well.It has kept the temp in our bedroom down about 3 degrees which was impossible before.Used to get to 78 no matter what I did. Now it sits at 75. Which is cool enough.Wish I bought one years ago. Always had other ideas that sort of worked. But this is it.It seems well built. User friendly. I just let it run all day. At least for now. May test the other features soon.It fit 4x10 effortlessly. 4x10 is the hole. Not the top of the register.It's very quiet. We use a fan anyways. And this noise disappears.Without the fan it's quiet. Could take the place of fan noise too. If on high setting.

works well once you figure it out. My kids 2 bedrooms are on the upper level, full sun all day. their rooms can never cool down in the summer ( midwest heat/humidity) They are very happy with how much cooler their rooms are now, and while I would find it way too loud to have running in my room, they don't mind how loud the fan is. You can adjust the level of the fan though, (higher is louder obviously) they just prefer it running at an 8 out of 10 for a boost of cool air.

I have an upstairs that runs too warm all summer. It's big room with one vent fed by at least a 15 foot run of 12" duct. I had been planning to sever the duct and install an inline duct fan up in the attic and either use an expensive pressure switch or tap into the thermostat wire with a relay, but this vent register booster is a much easier to install and less expensive solution - and it's working pretty well!Plugging it in is the only tricky part, but I was able to plug it in up in the attic so no cord is visible. I took my old vent register off and I probed around the edges with one of those wiring fishing rods until I found a gap where the rod could push up into the attic. Then I climbed up in the attic, plugged it into an outlet up there and then taped the end of the cord to the rod so I could pull it back down into the room. The AC register booster has a short 6 inch lead attached to it, and the rest of the wire connects to that. It's obviously heavier than a plain vent register, so it was bit difficult to install because I had to use both hands to hold the register up there and connect the wire and then reach for the screw and screwdriver to fasten it in place without letting go of anything.The thermostat measures the air in the duct so that you can set it a temperature below the normal room temperature, but above the temperature you're reading in the vent when the AC is on and it will turn the fans on only once the cold air starts coming through. Mine started off reading 68ºF in the duct, but after a while I checked it again and the reading was 66º, so I figure it's pulling the cool air through the duct faster and not allowing it to heat up in that long duct in the attic. I still need to replace my AC system, but I can tell that this room is noticeably more comfortable after installing this inexpensive solution first.

I waited a month to see how this works. Used on ceiling in a low airflow bedroom that is far from the main stack. On speed 9 it probably doubles the airflow to the room. We use a white noise machine to sleep, so the sound of the vent fans is drowned by that. It definitely improves air flow and cooling. One thing to be careful about: One night it got VERY cold, and this is why: it got cold outside (49F), we didn't turn the heating on, and the temp in the register dropped below 68F, which is the point when the fans activate. So it ran all night because the temp got low and it "thought" that I turned on the AC.All in all, it worked great for me.