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This is a direct comparison review between the three most popular currently available twin window fans:
Bionaire BW2300 Twin Window Fan with Remote Control
Holmes HAWF2043 Twin Window Fan
Honeywell HW-628 Enviracaire Twin Window Fan
If you are interested in purchasing any of those widow fans, read on...
I didn't intend to have to do this review because I didn't intend to purchase more than one of these fans. I can tell you now that all of these fans are super cheaply designed and built and none of these fans are perfect, but in my opinion, one is worse than the others.
Holmes HAWF2043 Twin Window Fan: my rating 3 of 5 stars
I first purchased the Holmes HAWF2043 unit. It was lightweight and fit the window nicely although I had trouble with the extender which is located on the right side. The locks for the extender are located on the right side along the top and bottom edge of the fan, which is supremely stupid because as soon as you place the fan in your window frame and put weight on it, the bottom lock locks and you can not move the extender. I mean, what rocket scientist thought of this? So you have to unlock the locks before you place the unit in the window AND keep weight off the bottom lock until you have the extender adjusted to where you want it. This is not easy. And the lock mechanisms can be difficult to move. At the time, I could not imagine anything worse, but I was wrong as I found out with the extenders on the Honeywell unit, which I will go into in the next paragraph. This Holmes unit has the best placement of the power cord which is in the lower left corner... the location is high enough as not to interfere with the bottom of the window frame. This unit has two speeds, high and low. The controls are easy to operate. In fact, there is only one button and two switches. The button cycles through the high and low manual speed settings and then though the automatic temperature presets which are at 60, 65, 70, 75 & 80 degrees fahrenheit. If you set it at one of the temperature presets, the unit will turn off once the room reaches that temperature. It seemed to work although I did not have the opportunity to see how accurate that function is. The two switches set the direction of the fans to either intake or exhaust which can be done on each fan independently, so you could have one fan on intake and the other on exhaust for quickly exchanging room air with fresh air. This unit has 8.5 inch fans and they are relatively quiet at both speeds, naturally high is louder than low, but don't expect silence. I own a Kill-A-Watt P3 energy meter and this unit used 46 watts on low and 63 watts on high. I would have been happy with this unit except that two days into using it, the right fan started working intermittently. Of course, that is unacceptable. Returning. I give this fan 3 out of 5 stars because I feel that if you get a good one you'll be happy with it, but don't expect anything great. FYI: Holmes is a division of Sunbeam.
Honeywell HW-628 Enviracaire Twin Window Fan: my rating 2 of 5 stars
So with the right fan not working correctly on the Homes, I ordered the Honeywell HW-628. As soon as I saw it, I knew I was not going to be happy with it. For one thing, the unit has 7 inch fans compared with 8.5 inch on the Holmes. So in order to move as much air, the fans would have to run much faster and the unit will be much louder. Time to install... I previously mentioned that the extenders on the Holmes were poorly designed, but the extenders on this were MUCH worse. First of all, this unit has two shorter extenders on both the right and left sides instead of one longer extender like the Holmes has. Second, the four extender locks are, get this, located on the BACK of the unit, the side facing out the window! How are you supposed to set those? It was impossible for me. I ended up jamming the extenders into the window frame in order to keep them extended. Okay, so I finally get the unit in the window and turned it on. I found out immediately that my thoughts about the smaller fans, higher fan speed and noise were true. This thing is LOUD. Super loud. And buzzy. In fact, I'd go as far as to say that it is downright unruly. There is no chance you would use this in a bedroom even on low speed. The controls were easy to use although not completely intuitive. There are three speeds available on each fan, low, high and super high. You have to set each fan separately, which I think is stupid. I cannot imagine a scenario where I would want one fan on high and another fan on low, etc. The temperature setting dial is also extremely stupid. There are no temperature markings. According to the manual, you are supposed to keep the unit on until the room reaches a temperature that you like and then turn the dial back until the unit cycles off. Seriously? Each fan has its own direction switch for either intake or exhaust. The power cord is located on the bottom center of the front of the unit and its mounted too low so that it interferes with the bottom of my window frame. Who is designing these things? The one feature it had which I liked was that the grilles were directional and could be rotated to direct air in a 360 degree arc. On the power consumption front, this unit used twice the power as the Holmes! 97 watts on low, 109 watts on high and 120 watts on super high. My unit was defective in that the switches for the right fan are wired incorrectly such that low is high and high is low, but super high is still super high... odd. Returning. Due to the noise level, I would not recommend this unit. I cannot understand how it has 4 of 5 stars and as of today, 262 reviews. Incomprehensible.
Bionaire BW2300 Twin Window Fan with Remote Control: my rating 4 of 5 stars
So after the poor experience with the Honeywell (They put their name on that piece of junk? They are a defense contractor!), I purchased the Bionaire BW2300 hoping for better luck. First thing I noticed was the similarity between this unit and the Holmes. That is because they are both made by the same company. Bionaire, like Holmes, is Sunbeam. It has the same right side extender locks as the Holmes, but after the experience with the unusable rear locks on the Honeywell, I was happy to see them! One unwelcome difference is that the power cord is located on the bottom center of the front like it is on the Honeywell, and its also too low like it is on the Honeywell. I mounted the unit in window fairly quickly and turned it on. Its got three speeds, low, medium and high. It uses 8.5 inch fans like the Holmes and it is relatively quiet, although I think it may be ever so slightly louder than the Holmes on high. The controls are all electronic and it has an electronic temperature readout and thermostat. It is very easy to use. Simply choose a fan speed and put the unit into intake, exhaust or one fan on intake and the other on exhaust (air exchange mode). You can use it either in manual mode where there is no temperature control or you can set a temperature for the unit to reach and then turn off (automatic mode). This is easy to do using the simple up and down buttons to the right of the large temperature readout or you can use the remote control. Once you set it, it will remember your settings if you turn it off as long as you don't unplug it. The remote control works well and it allows you to control all of the fan's features and functions remotely: on/off, fan speed, air direction, temperature and to toggle between automatic and manual mode. Finally, there is a button to change the brightness of the temperature readout, although you cannot completely turn it off. The power usage was similar to the Holmes. The Kill-A-Watt read 43 watts on low, 49 watts on medium and 64 watts on high. Unlike the most popular review for this unit, my temperature probe was located in its proper track and it seems to work well. I've been using it for three weeks now without issue and so this is the keeper. 4 of 5 stars for this. Its not perfect, but in my opinion, its the best of the three.
Just remember that with any window fan, one of the most important things is setting up a ventilation route.
In order for a window fan to be most effective, you have to have a second open window for either:
drawing in fresh air if you put the fan in exhaust mode.
or
exhausting room air if you put the fan in intake mode.
If you don't have a second open window for either mode, you'll either create a vacuum or pressure balloon, respectively and either way, you'll not be moving much air which is what a fan is all about in addition, you'll be overheating and likely killing the fan's motors. The second open window can be in another room or on another floor or it could be a screen door, but you need an unobstructed, open source of fresh air with the fan on exhaust or an equally open window for air to exhaust through if you put the fan on intake mode.
Of course, you could use the fan on exchange mode where one fan pushes air in and the other exhausts, but this is not ideal as my observation is that this mode is not nearly as efficient the other two.
Also remember that the outside temperature rules everything. In order for a fan to cool a room, in my experience, the outside temperature needs to be at least ten degrees cooler than the inside temp, or it needs to be falling, like it typically does at night. If the outside temperature is about the same as inside or warmer, then you'll not be cooled off by a fan. Humidity counts, too. High humidity = bad.
The window fan works well for me in the evenings/nights where the outside air temperature drops 10 or 15 degrees but the inside air temperature would stay high, even with all the windows wide open as often happens without any significant wind or breeze. With the fan on and with the windows and doors set up correctly, the upstairs bedrooms stay within three or four degrees of the outside temp for me without having to turn the air conditioning on in the spring and fall. I find intake mode most effective for me. And again, remember that the daily effectiveness of any window fan will depend a lot on the outside temperature and humidity level.
As far as these fans are concerned, I would say either get the Holmes HAWF2043 or the Bionaire BW2300, but stay far away from the Honeywell HW-628. Good luck!
UPDATE July 6th, 2012:
I've had the Bionaire BW2300 for just over three years now. It's holding up quite well. I use it all the time and it works as well today after three years of use as it did when it was brand new out of the box. The remote control and the full temperature controls are nice! I'm very happy with it. Its one of the best things I've ever purchased.
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I am a big fan of this one. (yuck, yuck) Actually, the fan works very well. It's speeds are noticably different depending on your need and the thermostat settings really work. I bought one for a room where and AC was not practical and it worked like a charm. I now have three of them and even in the largest room, it does a great job. Not silent, but not distracting. A great buy especially with the three-year warantee.
Best Deals on Holmes HAWF2043 Dual Blade Twin Window Fan with One Touch Thermostat
I live in Southern California, in a Two Story home, where temperatures can reach upwards to 85 degrees inside. When the sun goes down, temperatures can be as low as 55 degrees, but without a breeze, you can't get that breeze in your home. With this fan, I can now bring in that cold air, and cool down my second floor in no time. I bought three, to use in all my rooms, to cool the whole floor, and now can limit the use of my air conditioner and lower those high electric bills. As for the comments about noise being a problem, I don't hear it. If anything, it is a constant frequency which will drown out other unwanted noises, like that of white noise from a water fountain.
Honest reviews on Holmes HAWF2043 Dual Blade Twin Window Fan with One Touch Thermostat
I recently bought two of these for my apartment. I lack air conditioning and don't really have the money for a decent window air conditioner, but I won't really need it now that I have a couple of these. I put one at one end of the apartment set to "intake" and one at the other set to "exhaust" and now there is a nice little breeze (not strong, but perceptible) through the whole apartment, keeping the air from getting stagnant and oppressively hot. I wouldn't recommend these as a replacement for air conditioning for larger apartments or houses, or for people who really can't stand heat and humidity at all (I grew up in the deep south and don't mind humidity), but if you're looking for something to keep the air in your home breezy and fresh, this will get the job done. The controls are easy to use and the set up is self explanatory and takes only a minute. They're also pretty lightweight and durable, which is a plus for me since I move fairly frequently. And at $30/each, they're a lot of bang for your buck. I am very pleased with my purchase.
Find helpful customer reviews and review ratings for Holmes HAWF2043 Dual Blade Twin Window Fan with One Touch Thermostat
I bought this fan because it is starting to get hot in New York and I couldn't stand it anymore. I ordered this fan because it was the highest rated window fan on Amazon, but now I think the system is rigged because this is the worst fan I've ever bought. The fan has less power than my own lungs. There are several settings, none of which seem to do anything, and when the fan is on it's highest "setting" it blows with almost no power. If I could give it zero stars I would, but here I can only give one star. I'm sending it back to Amazon. I do NOT recommend this fan unless you just want to put something in your window that blocks your view and doesn't blow at all. I have no idea why people would recommend this fan, it really does not perform
