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If you’re setting up a dryer in your home for the first time, you may encounter problems when installing your ductwork, depending on where your dryer is located within your home. Ideally, your dryer should be as close to an outside wall as possible, which allows the dryer to expel hot air, moisture, and lint more easily.
If your dryer is too far away from an outside wall, you may need to install a dryer booster fan to compensate lack of strong airflow. A dryer booster fan not only improves the airflow in your dryer duct but also helping to reduce energy costs, by decreasing dry time by almost 50% on electric dryers.
In this article, we’ll be sharing with you everything you need to know about how dryers and dryer booster fans work, as well as what you can expect when installing a dryer booster fan for the first time.
First, How Does a Dryer Work?
To understand how a dryer booster fan works and how it can make your dryer more efficient, it may help to know beforehand how exactly a dryer works. Let’s quickly go over how dryers produce heat and how they generate airflow.
How a Dryer Produces Heat
There are actually a couple of different ways that dryers produce heat. Modern dryers use either electricity or gas to create heat; both of these methods have advantages and disadvantages.
The main advantage of electric dryers is their relatively low initial cost; gas dryers are generally more expensive to buy than electric dryers. However, gas dryers are more energy-efficient than electric dryers, are cheaper to operate in the long run, and are better at drying clothes quickly.
In the case of electric dryers, heat is generated by sending an electrical current through a heating coil similar to the one in an electric oven.
Related: How Much Does it Cost To Replace Heating Element in The Clothes Dryer
The heating coil creates resistance to the current, which in turn generates heat. As the heating coil increases in temperature and heats up the surrounding air, a blower fan moves the hot air through the dryer.
Some Gas dryers contain a pilot light like the ones you’ll find in gas fireplaces. The pilot light ignites the gas in the dryer, which of course creates heat. Just like in an electric dryer, a blower fan circulates this heat within the dryer.
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It’s worth mentioning that regardless of how your dryer generates heat, all dryers use electricity to power their various other components.
How a Dryer Generates Airflow
For a dryer to dry your clothes properly, there needs to be not only a sufficient amount of heat, but a sufficient level of airflow. Having enough airflow within your dryer helps remove moisture from your wet clothes more quickly.
When it comes to air circulation within a dryer, there are two types of dryers to take note of; vented dryers and ventless dryers.
In a vented dryer, fresh air is brought into the dryer, heated up, passed over your clothes, and then forced out of your dryer through a duct.
Ventless dryers, on the other hand, work by recycling the air that is already in the dryer. After the hot air passes over the wet clothes, it gets sent through a heat exchanger, which cools the air and allows the moisture to condense and flow into a drainpipe or drip pan.
The dried air then gets sent back to be reheated, and the cycle continues.
Does My Dryer Need to Be Vented?
You may be wondering if it’s even necessary to vent your dryer to the outside to begin with, since all that’s being produced is heat, moisture, and some lint. In actuality, it can be a pretty significant safety hazard to leave your dryer unvented; here are some of the reasons why this is the case.
Related: Why Does Dryer Vent Keep Getting Clogged?
Dangerous Gas
For gas dryers, it’s absolutely essential that you have a vented dryer with ducts leading outside. The burnt gas in these dryers produces carbon monoxide, which can be incredibly dangerous and even fatal if you allow it to build up within an enclosed space.
Fire Hazards
When your clothes tumble around in the dryer for a while, they produce lint. Most of the lint gets caught in the lint trap, but some of the lint is expelled along with the rest of the dryer’s exhaust.
If your dryer is being vented inside, this can cause lint to start accumulating in the area near the dryer’s exhaust port. Lint is extremely flammable, and if the buildup of lint in your home happens to come in contact with a spark (say from a worn electrical wire), a fire can easily start.
Moisture/Mold Problems
Venting your dryer inside will generate excessive amounts of warm, moist air inside your home. Unfortunately, mold loves to grow in warn, moist conditions, so by venting your dryer inside you’re basically inviting mold to come in and make itself at home.
In addition, the extra moisture in the air can cause structural damage to your home over a period of time, especially if your home is built mostly with wood. Prolonged exposure to moisture will cause the wood and drywall in your home to start rotting, which could potentially make your home very unsafe to be in if the problem goes on for long enough.
Poor Air Quality
Last but not least, venting your dryer inside can decrease your home’s air quality by dispersing tiny particles of lint throughout your home. Lint isn’t toxic or anything like that, but for people with asthma or dust allergies, an excessive amount of lint in the air can make things pretty uncomfortable.
What Is a Booster Fan for a Dryer?
Like we mentioned in the introduction, a booster fan is used to improve the airflow in a vented dryer, particularly for vented dryers with a long length of ductwork leading to the outside. By improving the airflow from the dryer to the outside, there’s less back pressure in the dryer, which allows moisture and lint to escape more easily.
Not every dryer needs a booster fan, and in fact you probably shouldn’t get one unless you really need it, since dryer booster fans can be somewhat expensive to buy and install and also add complexity to your dryer’s setup.
Related: Dryer Vent Repair – Should You Fix It By Yourself?
If you’re wondering whether you should invest in a dryer booster fan, the main thing you should take into account is the length of your ductwork as well as how many bends are in your ductwork. In general, this is the maximum length your ductwork can be and the maximum number of bends it can have without needing a dryer booster fan:
- No bends – 25 feet
- 1 bend – 20 feet
- 2 bends – 15 feet
- 3 bends – 10 feet
In such cases where you actually need one, a dryer booster fan can decrease the drying time of your clothes by as much as 50%.
How Does a Dryer Booster Fan Work?
The way a dryer booster fan works is pretty simple. The fan is mounted somewhere along the ductwork leading from the dryer to the outside, and generates airflow within the duct that helps move everything along more quickly.
Dryer booster fans automatically detect when the dryer is running, and are able to turn themselves off and on; there’s no need for you to manually switch the fan on when running the dryer.
Dryer booster fans know when to turn on via one of two methods; either a pressure switch or a current sensing relay.
In the case of fans that use a pressure switch, these fans use a sensor in the dryer duct that detects the increase in air pressure when the dryer is running. For fans with current sensing relays, these work by detecting when the dryer is drawing power.
How Much Does a Dryer Booster Fan Cost to Install?
Like we said a couple of sections ago, dryer booster fans can sometimes be fairly expensive to buy and install, depending on how high-end the fan you’re considering is. For a decent lower-end fan, you’re probably going to be looking at a cost of about $150, while high-end fans can cost anywhere from $300 to $500 or more.
Of course, this doesn’t include the cost of the installation, which you’ll have to pay if you’re not installing your fan yourself. Depending on the company you use to install the fan, the installation fee might be a pretty significant fraction of the cost of the fan itself.
How to Install a Dryer Booster Fan
Fortunately, it’s not that hard to install a dryer booster fan on your own if you want to save some money on installation costs. Here’s what you need to do to properly install a dryer booster fan:
- Find a good place to mount the fan. Ideally, the fan should not be closer than 15 feet to the dryer itself, to prevent excess lint from being drawn into the ductwork. You should also mount your fan close enough to an outlet for you to plug it in easily.
- Once the fan is mounted, connect the ductwork to the fan. If you’re hooking up a dryer booster fan to existing ductwork, you may need to cut a section out of the ductwork in order to do so.
- Use aluminum tape to seal the ends of the ductwork around the ends of the fan. You’re all done!
