DenwennyDenwenny IP55 Grade 540CFM Crawl Space Ventilation Fans with Dehumidistat, 8.7inch Basement Vent Fans with Isolation Mesh, Freeze Protection Thermostat Ventilator Fan for Crawlspace, Attic, Garage

I initially ordered some fancier digital model, but returned it and opted for this one instead. We live in a very dry area but have still had some ground termite problems. Was advised to install a fan in the foundation crawlspace. This fan was installed in crawlspace and when facing the controls (under the house) blows the air OUT of the crawlspace. This is what we needed to try and keep the space better ventilated and drier.

Crawl space

I bought this crawl space vent fan to pull air out of crawl space. I have one section of my house which is just a couple hundred square feet. The air flow is perfect. The flow is sufficient and it has a big fan. The unit is very easy to mount and it has over sized flange with a long hole for setting screws. I mounted it on the wall of the crawl space. Overall i am impressed with the fan, mounting and flange. The humidistat is good and works great!

Installed it about 2 weeks ago in the garage to cool it at night during the summer. It does cool it by an average 5-10F depending on the temperature outside. Can't say how long it'll last, but so far so good 🤞

We all think of things we need and find something made for something else that will work. I know these are designed for crawlspaces but we have and RV that needs ventilation for the cooling fins on our refrigerator. We have an ammonia cooled refrigerator in our RV. In the summertime it takes it a long time to cool down because the cooling fins do not get enough air passing over them. This is just the right size to fit onto the cover of the compartment. I tried the fan first to see if it had enough get up and go to work. Well, it does and more. This thing really blows and in nice and quiets. It does use a humidistat but it will always be humid enough for the highest setting. Not to get to technical but I will run it through a relay that will turn it on when the refrigerator is turned on. With sufficient air passing over the coils we should be in great shape. I will not know for sure until summer but that is the goal. If you are looking for a powerful and quiet, humidistat fan, this is a good choice. You can find crawl space fans from a little to a lot as far as pricing. This is probably right in the middle. I like the 540 CFM that it puts out and the 2 year warranty. I recommend this fan.

This crawlspace fan is a nice way to reduce the humidity in the crawlspace or any other area you want to install it. I did have to run electrical to the area that I needed it in... a low spot in the crawlspace that seemed to be a lot damper than most of the rest of the crawlspace and was near a vent. It gives off a little hum when it runs, but given that it is under the kitchen area, I don't see that as a problem. There is a switch to set the humidity level and the unit shuts off or turns on when the humidity level triggers it. I cannot tell how sensitive it is, but having humidity sensors before for chicken hatching, I can tell you that they work pretty well. Overall, I can see that this will help in the area and will keep any sort of mold or other wet rot issues at bay and for the price of this unit, the cost of potential repairs is well worth it.

The media could not be loaded.  We purchased the vent for the attic but given its size and cfm output we decided instead to install it in our crawlspace. The unit was super easy to install and it came with a plug so it didn't have to be hard wired into the electrical system. I connected it to the receptacle plug box my sump pump is plugged into and the unit runs flawlessly. Really like that it shuts down at 35 or lower, and we just had a couple of 30 degree nights here and the unit did not disappoint.There is a bit of noise when it runs, but all vent fans have at least some noise, and this one doesn't stand out as a "louder than usual" model. That said, we can hear a very low hum from under the house in the rooms adjacent to the unit itself. It's not bad or distracting and in fact, if you're a fan sleeper, you'll be happy.It's a little louder outside, but I have the unit located on a lever vent that sits next to my garden table area at the back of the house. It is definitely noticeable but again, I'm basically standing about 3 feet from it so its not a problem.Definitely worth the money, it looks like its durable enough to last a long time - which is a huge bonus if your crawlspace - emphasis on "crawl' - is anything like mine.

This is a great ventilator as you set it for the desired humidity level and it will turn on/off as it senses the humidity level.Due to the fact that the sensor needs to detect the humidity, I'd suggest to install this in part of your crawlspace or basement where you experience the most damp area's, ensuring the sensor triggers to expel the damp air.The fan is by no means silent, but does not give off a lot of noise.It is a high quality product that I'm hoping will last a few years given the relatively high cost to replace it.