Suncourt Register Booster Fan, Quiet Vent Fan Booster for Floor Vents HC600 | Vent fan booster fits 4x10, 4x12, 6x10 & 6x12 registers; auto on/off; up to 300% more airflow; made in USA since 1988

The unit out of the box is actually great if you don't mind the bearing noises/minor rattle. The fans are loud so if you don't mind that they will be fine. While I don't mind a little white noise in the background, when it comes to my computer room with three workstations running it can get warm and I have all of my systems setup to run silently so I can work and have meetings. This unit has loud fans which to be fair push a lot of air and work great. Keeps the room significantly cooler when running. On that note I modified mine and changed out the fans with the be quiet 92mm fans that push about 33cfm. This is maybe half of what the originals put out but the difference in sound is unquestionable. Other than the sound of the movement of air they are completely silent and I just let them run at full speed. great "as is" if you need a room to be cooler or warmer but with modification if you want to cut down the noise it becomes amazing.

As is this is an OK floor booster that really helps move extra air into a room. It has a pair of high-flow 92mm computer fans inside that best I can tell move about 55CFM each. I opened the unit up and some google-fu on the model numbers of the fans revealed the chinese supplier's site with specs. Really about 55 CFM is about the max air flow you can get out of 92mm fan. Collectively they move ~100 CFM of air with no obstructions. So the unit pushes *quite* a bit more air than the competition's offerings, at least on paper. That said these things are not miracles. Pretty much any in-vent booster will change the room's temperatures by about 5 degrees at most. This one has the CFM's to do about that. Its actually moves MUCH more air than Susncourt's booster model that sits over the vent. On the pro side the housing is very nice, a nice obstructive brown color and fits neatly into my 4"x10" vents for a neat flush look. The cord could bother people but I have a plug near buy so it doesn't bother me. The temperature control is pretty standard thermostat And the unit has nifty LED lit lights and push-button controls. Trouble is the housing isn't the most brilliant design. The first big con is the intake grills. On the bottom side of the unit they molded in little grills that reduce the area for the intakes to about 40% of the area of a 90 mm circle. As other have noted, removing these will GREATLY enhance airflow upto that 100 CFM max. Since its on the side that inside the vent this will have no effect at all for safety noise. Fortunately if you don't care about your warranty they snip off effortlessly with some wire cutters. The second major con is the fans themselves. They work great, but they have a lot of buzzing bearing nose. So in addition to the white-nose whoosh of air there will be a grating buzzing coming from the fan's motors. However they are standard. The buzzing was about the same volume as a conversational voice, or a running shower for reference. If they noise is worth an ~5 degree change in the room's temperature is upto you. Now I purchased with the intent to modify. This product uses standard 12volt (2 pin) 92mm computer fans with molex mini connectors. This means that any one of the plethora of 92mm computer case fans will effortlessly fit inside the housing and wire up with a little doing. I ended up purchasing a pair of 44CFM Arctic brand "PWM" fans based on their reported lose noise, cheap price, and decent CFM. With a delicate touch I disassembled the housing (the top just clips on with plastic hook style clips, and removed the stock fans. This entire unit has no screws, its all plastic clips that need a firm but gentle touch to pry back to unclip the various parts without breaking anything. I then released the crimp on connecters out of the plastic plugs from the artic fans, did the same with with the stock fans after noting the polarity of the wiring (red is + black wire is - ). Now the attic fans are PWM as mentioned so they had 4 wires, but 2 of those wires are for reporting to the motherboard to control fan speeds. They are not necessary. So Artic was kind enough to label their 4 wires as PWM, RPM, +, and - in the specs for the fan. I released the terminals out of the 4 pin plug housing, took the 2 pin plug housings from this unit, and moved them, thus converting the artic fans to 2 pin 12v fans. I snipped off the extra wires that are no longer need (as they will never be installed in a computer) plugged in the new fans and closed up the whole unit. It now moves ~80CFM of air and is nearly silent. Now the only thing I can hear is the white noise of moving air, the motors and bearings are below my ability to hear them. Another reviewer here mentioned they used noctura brand fans. Noctura makes the nicest fans in the PC market, but the Artic fans were Seven dollars each compared to the $ twenty one each that the noctura's were. Thus I am not too worried if not matching up the amp-raiting on Artic fans burns them out and I need to replace them in 6 months or so. But yes I am happy with my purchase. I bought this for the housing and 12vot power system with the idea that I would be replacing the industrial grade, noisy fans. The fans suncourt picked would have been great for a server room where you could care less about noise, but pretty bad for a residential product.

These were absolutely life changing. If your HVAC cannot effectively reach upstairs, buy these now. We had 20 days over 90 degrees this month, and have slept so comfortably. Last Summer it was 71 degrees on the main floor and 85 degrees upstairs. I have recommended these to my neighbors, and those who actually listened have all reported back the same life-changing stories... along with being upset they've dealt with sweltering heat all these years when there was such a simple, inexpensive and effective solution. Some reviews mention the noise, but I say "whatever." Low speed is pretty quiet and works plenty well, and you'll get used to it in a night if it even bothers you at all. I could see someone complaining about the noise at higher speeds, but we've never needed them, and frankly you'd get used to it anyway--it's basically just white noise, and some people pay stupid money for white noise machines. Some reviews also complain about the power cord... Are you kidding me? For the benefit of a cool, comfortable night's rest, I could not care less about the cord. By way of scenario... We're in a three-story townhouse community built in the 70's with zero insulation on the front and back walls and four inches of attic insulation. Everyone in the neighborhood melts upstairs in the Summer or opts to camp in their living rooms or basements. The usual advice is to spend a few grand to better insulate the attic and open up the walls to add insulation. We got one of these after a neighbor recommended, were amazed at the results, and the next day got three more for the rest of the upstairs registers. What a small price to pay for virtually unbelievable results vs. adding attic insulation and tearing open walls and ceilings to install a split HVAC system. Side note, while these worked insanely well and I could have stopped, I kept going. I added R-38 unfaced insulation to the attic along with Reflectix radiant barrier to the roof deck, which both definitely helped even more--the HVAC is operating more efficiently with slightly lower power bills than last Summer. The insulation was obvious, but it was the radiant barrier that surprised me. I very highly recommend the radiant barrier, which truly lives up to the marketing and reduces the actual temperature inside your attic. It was in the low 70's when I installed the radiant barrier, and my attic was like a sauna. It was in the high 80's when I then installed the attic insulation (poor planning I know), but here's the thing... the attic was actually cooler than when I installed the radiant barrier and the outside temperature had been in the 70's. I could not believe the effect of the radiant barrier, and recommend to everyone (depending on your latitude).

i bought this over other models because I liked the fact that the motors are DC and therefore have the wall transformer and small wires that can be tucked under the baseboard moulding. This device is in the bedroom of a very active 4 year old and I didn't want a large cord running across the floor/carpet. As previously stated by other reviewers, you can hear this when it comes on. It's not loud, but the hum and vibration travel down your ducts and into adjacent rooms served by the same duct and also into the room below, if any. I have not tried cutting out the lower grill yet and I won't until I can also screw it down to keep out little fingers that might lift it from its home. UPDATE- I have cut off the lower grill and it is quieter and moves more air. No increased risk to little fingers as the slots in the grill were already large enough for my 5 year old to put her finger in, so- nothing to loose. There are 2 fans but only one appears to work at a time as they seem dedicated to either 'heat' or 'cool'. Since the 'cool' fan will never be used in my house, I wish that fan could be re-purposed to run along with the 'heat' fan. The buttons to set the mode and speed are flush. and while not a defect, they are EASILY pressed and change modes with any deformation of the register. Ours happens to occupy that narrow space between a bed and wall and when you use that space to make the bed, it is difficult to avoid stepping on the register. This deforms it (it is plastic) and invariably changes modes or fan speed as well as pop the power-plug out of the unit. Again- that is in our case but just going for full disclosure here. I would buy this again as it most closely matches our needs. Bottom line- it makes a HUGE difference in the temperature of the room.

Like many people's homes, our upstairs bedroom that is farthest from the furnace is always cold in winter and hot in summer. This simple, well designed product solved something that we've been "living with" for years. The alternative has always been to rip open the drywall in the basement ceiling and modify the duct work to provide a better balance between the rooms than what the register dampers were able to provide. That would have been a huge mess and cost thousands of dollars, which is why we'v been living with this problem for years. For a fraction of the cost, the problem was solved in seconds! The unit readily senses the small build-up in pressure that occurs when the furnace fan kicks on and starts the booster fans (you can set it to run all of the time, if desired). There is also a thermostat control and switch to select heating or cooling mode, so that it will turn itself off when the room is at the desired temperature. Fan noise? Well, of course there is fan noise - it has fans in it. Seriously? The unit is very quiet compared to the box fan that we use to set above the register to attempt to pull some more airflow out. I repeat my headline: This is a GREAT, inexpensive solution for a room with poor airflow.

We have a cape cod style home with central air, but the second floor master bedroom has never been adequately cooled. During the summer, it's typically 5-6 degrees warmer than the first floor. In years past we would sleep downstairs in the guest room during the summer. But these fans have worked amazingly well for us and have allowed us to use our upstairs bedroom even on the hottest days. I wish I had found them years ago! We have two vents in the bedroom, so I bought two booster fans. I played around with the thermostats, but I couldn't get the fans to come on consistently with the AC. I'm sure it's possible, but I gave up after finding another method that worked well for us. We use the booster fans like this: In the evening, when we come home from work the bedroom is between 79-81 degrees (our central air is set at 75 downstairs). I turn on the booster fans so that they will blow continuously. Three hours later when we go to bed the bedroom temperature has dropped to a comfortable 75 degrees. We leave the fans running all night and shut them off in the morning. After reading many of the negative reviews I was hesitant to buy this product, but it has worked so well for us that I would definitely recommend it. It reached 100 degrees outside yesterday, but our bedroom was still a cool 75 degrees by bedtime. The fans do make noise, but they're not too loud and it's white noise. My husband and I have had conversations with them running and it's no problem. We just started using the fans a month ago, so I will update if we have any issues.

Per other reviews I used Side cutters to clip out the grate on the back, it definitely helps warm the room, by sucking some of the warm air down the duct, (haven't had a chance to test A/C mode) only reason its not a 5 is it is a little noisy and a little fussy to adjust the auto on and off based on heat. But for the price its a good product that solves a problem especially if your room is large enough its not right next to you (in my case its in a bedroom and right next to my bed. if it was 6 feet away the noise would be fine but its 3 feet from my bed and 4 feet from head. so it is a little but not terribly annoying.

2 years later this thing stopped working, makes clicking noise but nothing works. DON'T BUY THIS JUNK.

It works well. My son’s room is always cold. The register is under the bed and has a deflector. This makes his room at least a whole degree warmer. The noise level isn’t bad. He sleeps with a fan and this is no noisier than that. And it only runs while the furnace is running. We will be using it in the summer with the A/C as well.

It helps to warm or cool the room. You do not need any modification on the duct. Directly put it in. Super easy installation. Noise or sound level is ok. Acceptable. But, it is additional sound in your room. Any duct booster fan can help to improve. It is better than nothing when you cannot have another open or other expensive major modification. It will help. I give it 4 star as I start using it only a week.

Easy to install and use. Works as it should. It's probably not going to solve all your heating/cooling issues, but it does help push the air from the ducts as advertised. A little louder than I anticipated but its good white noise if you can stand it. If you can't handle a little white noise, do not buy. It goes on and off when it senses the air coming from the ducts. You can set the fan to the lowest speed which is much quieter, but you will get less airflow. The small room this is being used in is at least 1-2 degrees warmer now.

Facile à installer, bruit trop élevé, ne chauffe pas.

Bought this to help warm up my daughter's room which otherwise receives very weak input from the vent. Firstly, the unit is just a temperature sensor wired to two basic PC fans, inside a cheap plastic casing. My initial reaction was why did this cost so much. I installed it and it seemed to work, albeit it was fairly loud. Next winter, the temperature sensor stopped working and the fans no longer kick in when hot air is blowing, no matter what setting I put it on. The only way for this to offer any benefit now is to leave it on all the time which is loud and wasteful. It's a good idea but poorly executed here.