Window fan direction summer


What to Consider When Choosing the Best Window Fan

Consider these features when navigating the wide and varied array of window options available today. Certain fan features will be more suitable for your space that are important to keep aware of to get the best cooling performance.


When shopping for the best cooling fan for a window, it’s important to consider which of the three types are best suited for the job. Window fans come in three different types: standard frame, desk, and floor.

Standard Frame: This type of window fan is designed to sit inside the window between the sash and the sill. Unlike a box fan, which simply sits on the sill, a window fan is installed using mounting hardware and has adjustable panels that fill the gaps on either side of the fan. Some standard frame fans can have either single or double blades.

Unlike other fan types, a standard frame fan is reversible, allowing it to function as either an intake or exhaust fan or both simultaneously. Since a standard frame is positioned inside the window, it does the best job of moving air in or out of a room.

Desk: A desk fan is smaller than a window fan but has a base that allows it to stand upright on a flat surface, such as a desk, without the need for installation. Unlike standard frame fans, which have a fixed position, desk fans have a tilt feature that allows the user to aim them up or down.

Floor: Floor fans, like desk models, fans are mounted to a base. They sit taller than desk fans and typically have larger blades, making them capable of moving more air. Like desk fans, they typically have adjusters that allow the user to tilt them up or down.


Since a window fan is intended to fit inside a window, it should not be larger than the window’s dimensions. For this reason, most standard window fans can fit windows about 26 inches to 34 inches wide.

When shopping for a window fan, make sure to choose a model that is just small enough to fit the dimensions of the window when open to ensure there aren’t large gaps around it that can allow warm air to enter the room or grant access to bugs should the window not have a screen. Many window fans have sliding guards on the sides that cover these gaps to prevent drafts from around the fan while also keeping bugs and rain out.


Window fans consist of a housing that holds one or two blades that are protected by a grate. These parts typically consist of either high-quality plastic or metal.

Blades: Window fans have either plastic or metal blades. Fans that have plastic blades are lighter and therefore more energy-efficient than metal fans. However, since the plastic parts aren’t as strong as metal, they don’t produce as much airflow.

Metal fans, though heavier, can endure greater stress and therefore can be equipped with bigger motors that produce more RPMs. As a result, metal fans can produce airflow of 3,500 CFM or more compared to plastic fans, which are limited to around 2,500 CFM.

Grates: All fans have either a metal or plastic grate that prevents objects or hands from coming into contact with the blades. While metal grates are more durable than plastic and can endure more abuse, they are also susceptible to rust and corrosion.

Housing: Most window fans have a housing made of a durable grade of plastic. Though not as strong as metal, the plastic housing helps to keep the fan’s overall weight down. Plastic is also impervious to rust and corrosion that can eventually ruin metal fans.


The airflow of a fan, an indicator of its cooling power, measures the velocity at which air enters or escapes a space. Airflow will be indicated either on the fan manufacturer’s website and on the fan packaging in cubic feet per minute (CFM).

While it may seem advantageous to buy a fan with the highest CFM you can find, a unit with a stronger airflow than the room warrants wastes energy. It’s more prudent to buy a fan with an airflow sufficient to cool the space where you’ll be using it. In general, you need about 1 CFM per square foot of space, plus an extra 50 CFM.

Most window fans have both an intake function (to draw in and circulate air from the outdoors) and an exhaust function (to force out indoor air or odors). Reversibility refers to the mechanism that allows you to change airflow direction. You’ll find manually reversible and electrically reversible fans:

Manually reversible fans require you to physically remove the unit from the window, flip it, and reinstall it to reverse airflow. Electrically reversible fans let you change airflow direction with the push of a button or flip of a switch, a major convenience with intake and exhaust functions at various times on any given day. For example, you may want to use the intake function while sleeping to draw in cool nighttime air and the exhaust function by day to expel hotter air.

Number of Internal Fans

One-fan units house one large centralized internal fan that enables air circulation. Because one-fan units bill themselves as “whole house” fans to cool the entire home, they tend to deliver a stronger airflow (more on that below). That said, their large single fan makes them bulkier and less efficient on the whole, thus slower to cool an individual room.

Two-fan (or “twin”) units feature two small side-by-side internal fans. They’re more compact, and while they offer a slightly lower airflow on average, two fans work more efficiently, cooling a room faster. Bonus: In a two-fan unit with electrical reversibility and independent control of the two fans via two intake/exhaust switches, you can have one fan perform intake and the other on exhaust simultaneously to maximize cooling efficiency and indoor comfort.

Noise Level

Fan manufacturers generally don’t list how loud their products are. Most window fans generate between 55 and 80 decibels depending on how close one is to the fan. Standard window fans produce similar noise levels to floor fans while desk fans, with their smaller blades, are quieter, operating at less than 40 decibels. If a fan is too noisy, the user can make it quieter simply by running the fan on a medium or low speed setting.

Additional Features

Many window fans come with some convenient extras, and certain models tend to look better in specific spaces.

  • Control panel: Window fans generally have a control panel on the front to turn it on and off, switch between intake/exhaust modes, adjust airspeed and temperature, as well as tilt or angle. Some models include a digital thermostat, as well.
  • Remote: Some models also come with a remote control for these functions, so you needn’t get up to operate it manually. This is a great bonus for those with limited mobility, if the fan sits in an overly large room, or in one where most of the seating is positioned far from the window.
  • Portability: Window fans designed to be portable usually have a lightweight build and may come with a handle and collapsible legs. Some are battery-powered for even more flexible usage.
  • Aesthetic: Window fans range from neutral white and black to sleek metallic finishes that ideally blend in with the surrounding frame. Fans with a shallow profile help achieve this unobtrusive look.

Installation and Maintenance

Most window fans are easy to install and maintain. Desk fans and floor fans are capable of standing on their own, eliminating the need for an installation that requires drilling holes and driving in screws.

Window fans fit between the sash and sill of the window and must be fastened to the window frame with screws to hold it firmly in place while it operates. Most window fans have panels that extend from the sides to close off the gaps in the window opening on either side of the fan.

What Is A Window Fan?

A window fan is a special cooling appliance that is created to be placed inside a window frame, and usually have expandable side panels that facilitates covering the window opening completely.

Most window fans have either one large fan or two A window fan is a great way to maintain comfortable temperature and purity of air inside a room. These fans not only come at a reasonable price but also are actually great alternatives to a central air conditioning unit. The operational cost of a window fan is low, which helps save on utility bills.

Most window fans have either one large fan or two small ones located next to each other. Also, most units feature two or three operational speeds. Some window fans available on the market are electrically reversible. This feature gives the user an opportunity to switch between intake and exhaust modes.

The older window fan models are made of metal and are somewhat heavy. However, they are more solid in comparison to modern units that are made of plastic.

Over the years, window fans have changed a lot—now you can enjoy a number of different features, such as built-in thermostats and adjustable grills. Thermostats are used to turn the fan off when the temperature in the room reaches a certain level. The adjustable grills are perfect for changing the direction of airflow.

Some more sophisticated models offer advanced electronic features such as a remote control, different speed motor controls and automated shut-down timers etc.

Talking about the diversity of window fans, it is worth mentioning that the options available are wide ranging. Some of the one-fanned units are very energy-efficient and are created for ventilating and cooling a single room. Other more powerful models are able to circulate air through the whole house.

In fact, a window fan has a great advantage in comparison to a room fan – it is able to circulate air within the room, bring in cool air from the outside or push hot/smelly odors from the inside to the outside.

air purifying and cooling applianceThis makes a window fan an ultimate air purifying and cooling appliance. In fact, window fans come in handy not only in regular small square rooms—their functional construction makes it easy for them to deliver fresh air even in irregular shaped rooms or large two story rooms.

In addition to the above mentioned facts, a window fan is a great alternative to air conditioners due to its environment friendliness. If a window fan is properly installed, it is capable of reducing the temperature by 10 to 20 degrees Fahrenheit or more.


Positive vs negative airflow

When fans pull in more air than they push out of a PC case, it creates positive pressure. Negative pressure pulls more air out, often creating a vacuum effect. For optimal cooling performance in a standard system, you want to be slightly more on the positive airflow side. (This setup usually results in more dust entering your PC, which you can mitigate with dust filters or more frequent cleaning.)

How do you achieve positive airflow? Easy: Just have more intake than exhaust fans, or run your intake fans slightly faster than your exhaust if they’re in equal number. Speaking of…

Common Window Fan Types

Whole House Window Fans

Cooling a house can be quite expensive when using the average air conditioning unit, but there is a solution for most that is cost-efficient and easy to install.

Window fans are becoming more common in households and are saving families on the average 50% on their cooling bill. People that live in the northern states can even save as much as 90%.

The way whole window fan house cooling works is when the temperature outside drops lower than the temperature inside your house the unit will draw the cool air from outside.

The hot air is then drawn through the fan and out the attic through the vents in the roof and attic.

Did You Know?

Whole house window fans are sometimes confused with attic fans, the main difference is attic fans cool only the attic whereas the whole house does exactly as its name states, cools the entire house, by opening the windows the fan is able to blow the cool air through the rooms.

There are several different brands and models of Window Fans on the market that are available for purchase.

Air King is one brand that offers a good selection of whole house window fan products. They make the 9166 series which can cool houses up to 1500 square feet, and every sixteen minutes the fan circulates the air completely through the house.

They also have the 9155 that is a 2-speed fan. The high speed will circulate the air in 7.5 minutes compared to the 16 minutes for a 1500 square foot house.

The Air King also do not need any maintenance and are insulated. When the fan isn’t on, the doors of the fan are sealed air tight.

There is also the top of the line Super-fan that is manufactured by R.E. Williams, this fan is powerful and quiet, it is able to absorb four rooms at one time. It is also the only fan that you can attach to a 12 inch duct to if you do not have the required free area of roof venting.

Environmental issues are at an all time high, with most of society and companies trying to go green and to conserve energy.

The whole house window fan is a definitely a machine that can help with conserving energy and save you money on your cooling bill.

The initial investment for these fans starts anywhere from 400 dollars and can range all the way to 1500 dollars for the top of the line Superfans.

The installation for these fans can take anywhere from 8-16 man-hours and there are even videos available on YouTube that show how to install them.

What Else You Should Know

For window fan typesyou can get the single type, or the double type wherein both fans are working different functions. One will suck in the air inside the room and blow it outside, while the other will serve as the passage way of the cool air from the outside going inside.

The size of the window fans will, of course, vary from one brand to another, features, and the type. But normally, one fan can measure at least 20 inches in diameter. So if you are getting a double type, expect that you have to make a provision for at least two 20 inches radius fans on your windows.

The best window fans will fit a normal width of a window. But just to make it safe, it is always best to measure the place where you intend to place the window fan and bring it with you when you are decided to buy the unit.

It is fairly easy to install a window fan unit. You just have to know how to work on the following:

  1. Mounting
  2. Brackets
  3. Side panels

You don’t have to buy them separately as they would normally come with the package of your window fan.

However, if you are not confident to install the unit, you may always get the ones that come with a stand which you have to place close to a large window. Or, you can always have a professional come to your place and ask him to install the unit for you.

Best Window Fan Pro Tip

If you intend to make all the hot air go outside, the best place to install your fan would be upstairs, where hot air is. For letting in cool air, you may want to install the unit at the lowest portion of your house where cold air is likely to be felt.

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  1. What window placements should I avoid? Typically, you should steer clear of placing your window fan in the proximity of parking areas, or garbage areas. That’s because the fan will redirect the odors from those areas into your house, and you don’t want that, of course. At the same time, it isn’t necessarily a good idea to locate a window fan near a fridge or a freezer. That’s because this will maximize the load of the unit.
  2. When is using a window fan not recommended? If the nighttime air in your area isn’t cool, then perhaps you shouldn’t invest in a window fan. At the same time, granted that the air outside is excessively polluted or humid, an intake fan isn’t recommended. There are other ways to cool your house.
  3. How to pick an energy-efficient window fan? Window fans are generally energy-efficient, but there are no particular window fan models that are exceptionally more energy-efficient than others. These fans have shaded pole motors with efficiencies of around 50%-60%. Since these fans are very small, they don’t use that much electricity, meaning they are going to save you some of the costs. Overall, they are all efficient in saving energy, but none of them is advertised as being exceptionally energy-efficient. Therefore, you will have to pick your own model according to your preferences.
  4. Will a window fan cool a room? Window fans are able to cool a room if used effectively. For example, if the temperature outside is cooler than the one inside, you can use the fan to draw cold air from outside and thus end up cooling your own room. This is a great option when you’re barely able to handle the hot temperature inside the room. But having window fans face inwards is not the only way to get the cooling benefit. Window fans that face outwards are able to blow hot air out of the room and replace it with cold air. So, since the cold air will enter your room from outside, the temperature will drop, and you will have a much better time in your own house. To make this work, you need to make sure the temperature outside is indeed cooler compared to the one inside. This is when the fan is most effective. If used properly, window fans can cool a room just like an AC does, so they’re definitely great choices in this regard.
  5. Is it bad to sleep with a fan blowing on you? Sleeping with a fan blowing on you is not the most dangerous thing. Many people make it seem like it’s a deadly thing, but it’s actually not that bad. Fans simply circulate the air and nothing more, so there’s no huge danger. However, there is something that will make you uncomfortable during sleep, which is one of the negative effects of fans being left on during the night. Basically, since fans make air move rapidly, they usually get rid of the humidity inside your room and dry the air out. As a result, your nasal passages are going to dry too, and this could get very uncomfortable and make you sleep badly. Thus, you’ll wake up tired the next day. Moreover, since they circulate air, they may also circulate dust, pollen, and other such particles. These could be irritable for someone with asthma or allergies. If you suffer from these conditions, the best decision would be to keep some distance between you and the fan so it’s not blowing directly on you.
  6. Are ceiling fans more efficient than rotating floor fans or window fans? Efficiency all depends on what you need the fan for, as well as how much air the fan moves per watt. These devices simply move air; thus, they don’t generate cool air or anything of the sort. Ceiling fans work amazingly in a room, but you can only feel the effect by sitting under them. Rotating floor fans just move the air in the areas you need. Window fans are more efficient here since they have the power to either get cold air inside the room or take hot air outside.