Vacuum cleaners are a necessity for any homeowner. They keep carpets, upholstery, and even hardwood floors free of all the messy residue from everyday life. However, despite their popularity, very few people know how these miracle workers really operate. We were so curious about the topic that we compiled all the information we could find about this common household machine. Keep reading to find out exactly how a vacuum works.

How Does A Vacuum Work? It’s Simpler Than You Think!

vacuum in a carpet

image source: Pixabay

So how does a vacuum work? Vacuum cleaners, although more complex, work much like a straw. They use powerful airflow and suction to pick up debris from surfaces. Once inside the machine, the dust and debris are trapped in either a bag or canister—which ensures that the air that exits the vacuum is clean and free of impurities.

On the outside, the machine looks fairly complex; however, the mechanics of a vacuum and their functions are actually quite simple. The standard vacuum has six main components including an intake port, exhaust port, motor, fan, porous bag or canister, and a structure that holds all the other components. These parts are found in most vacuums despite the wide range of products on the market. Not only do they share much of the same parts, but they also operate under the same principle to function: suction.

How Does A Vacuum Work? Suction, Filter, And Release

vacuum cleaner in a carpet

image source: Pixabay

When you turn on the vacuum cleaner, three central things occur. First, an air current flows into the motor. The motor causes the fans inside the machine to turn rapidly. These fans have custom angled blades that push the circulating air up towards the bag and away from the fan. This makes the area below the fan, or the area facing the floor, a low air pressure area. Air always moves from areas of high pressure to low pressure so this allows the motor to create the suction that lifts debris. This process is very similar to what happens when you suck on a straw.

Next, the intake port of the vacuum uses suction caused by the air pressure system to pick up dust and debris from floors or other surfaces. Many vacuum cleaners, along with a fan, come equipped with a rotating brush that sweeps the floor. These brushes are either manually powered by the back-and-forth motion of the machine or electrically rotated. Either way, the friction caused by the brush loosens the trapped dirt particles that remain in porous fabrics such as carpet. These impurities would usually not have been picked up by the air pressure alone. The brush dislodges the dirt and moves it to the surface where it will be picked up easily.

Once the vacuum cleaner has sucked up the dust and debris, a hose inside the machine directs the impurities to a canister or dust bag. This is where all the dirt is trapped to keep the circulating air clean and free to move out by the exhaust port. The dust bags inside vacuum cleaners are made so that only air can pass through them not and debris. The bags are permeable enough so that the air can flow freely but are still thick enough to trap large particles, dirt, and dust from returning to the floor.

HEPA filters, another filtering system inside the machine, also help ensure that the air leaving the vacuum is clean. HEPA filters cover the area from where the air exits from the exhaust ports. These filters are vital because without them the vacuum is rendered useless. HEPA filters make sure that debris and dust particles do not escape into the room as the clean air filters out.

Now that we’ve discussed just how does a vacuum work, let’s consider what makes a superior vacuum.

What Makes A Superior Vacuum

vacuum in a wooden floor

image source: Pixabay

As discussed, the majority of vacuums work on the same principle. However, all machines are not created equally. The power, capability, and effectiveness of a vacuum cleaner depend on a few factors. The size of the intake port, the flow of the air passageway, and the power of the fan will affect the power and capabilities of a vacuum.

Intake Port

The fan inside a vacuum cleaner moves at a constant rate, therefore, the amount of air moving through the vacuum also remains constant. No matter how big or small the intake port is, the vacuum will have to accommodate a certain number of air particles every second. However, by making the intake port smaller, the individual air particles are forced to flow more quickly so that they all get through the port in the same amount of time. The faster the air particles move, the more airspeed increases and the more the pressure inside the vacuum decreases.

The lower the pressure, the better the suction force is for the vacuum. In short, smaller intake ports create a stronger suction force. The narrow vacuum attachment has more power and can pick up more dirt and heavier particles than wider attachments. When shopping for a vacuum keep these scientific principles in mind to make sure you get the most powerful vacuum cleaner.

Power of the Fan

Another important facet of a vacuum cleaner is the fan. In fact, the one-word answer to the question “How does a vacuum work?” is the fan. As mentioned, the fan is what circulates air inside the machine and creates the suction-producing pressure systems. The vacuum’s fan has to spin at a good speed in order to generate proper suction. That’s why it’s important to do your research and check fan speeds, among other variables, before you invest in a vacuum machine.

Proper Air Flow

It’s no coincidence that cleaner vacuums work better. When a vacuum has a fresh filter or an empty bag, vacuuming is much easier and the machine is more effective. This is because when a lot of debris builds up in the vacuum bag or on the filter, the air has more resistance on its way out. The drag from the debris barrier makes the air move more slowly. This issue is very common in older vacuum cleaners that suck in dirt and impurities directly into the bag. As the porous bag catches the dirt, the air leaving the machine is relatively clean. However, the air is often slightly dusty as it filters back into the room.

Bags And Filtration

Another common issue with air flow, specifically in bag vacuums, is that the more you vacuum, the more the bag fills up and the amount of empty air the machine can hold decreases. This makes it so that the vacuum’s suction abilities are gradually diminished. With bag vacuums, the longer you go without emptying the bag or canister, the worse the air flow and suction weakens. A quality bag vacuum will have both a filter bag to secure the majority of dust and a micro-filter to further clean the air that will exit the machine.

Multiple filtrations ensure that the air expelled from the machine doesn’t push more dirt out. Double filtration systems keep the vacuum running longer because they will keep the machine from getting clogged with debris. However, many people find emptying the bag a dirty and dusty nuisance. Cyclone vacuums offer a unique alternative to traditional vacuums without the hassle of emptying canisters or worrying about decreased suction and air flow.

If you need a powerful vacuum with continuous productivity, we recommend the Dyson Ball Multi Floor 2 Upright Vacuum Cleaner. This cyclone vacuum does not have a filter or bag system. Instead, air filters through the machine in a stream, going through one or more cylinders. The air flows in a quick spiral path much like a roller coaster or clothes dryer. As the air shoots around in a high spiral, the dirt particles are pushed away from the air stream. This results in the dirt being separated and extracted from the air without ever needing a filter, and impurities simply fall and collect at the bottom of the cylinder.

This cyclone system eliminates the need to replace bags as you would with tradition vacuums. It also ensures that your machine won’t suffer in performance or suction as it sucks up more dirt. It’s multi-functional, light, easy to maneuver, and it automatically self-adjusts to any surface including carpet, vinyl, wood, and tile floors.

Frequently Asked Questions

Why does a vacuum create suction?

The tip of the vacuum nozzle and the tube through which it sucks dirt is large enough to allow optimum airflow yet small enough to create a wind tunnel. Without getting too technical, this allows the vacuum to create suction efficiently. 

What type of motor is in a vacuum cleaner?

A universal motor is typically used as suction motor across vacuum cleaners. The universal motor is a series DC-motor that is specially designed to operate on alternating current (AC) as well as on direct current (DC). Universal motors have high starting torque, operate at high speed, and are lightweight.

Are vacuums AC or DC?

It depends on the make and model. Some vacuums use an AC motor, while others use a DC one. Whichever you might choose, the power and efficiency varies thanks to multiple factors. However, do keep in mind that brushless motors are usually DC. While this isn’t a major factor for choosing a vacuum cleaner, it can still make or break someone’s purchase depending on what power grid they’re using.

What is the RPM rating of a vacuum cleaner motor?

Most vacuum cleaners fall around the value of 10,000 RPM with loads of torque to suck up every bit of dust, pet hair, and so forth. You might be able to find even more powerful models at higher prices, but the rule of thumb is that 10,000 RPM is standard.

Is 2 HP good for a vacuum?

A 2-HP motor good enough for most vacuum cleaners. It’s enough power for basic tasks, including sucking up pet hair.

Is a 3.5-HP motor enough for a shop vac?

Yes, it’s great for sucking up water, but it might be a little too much for drywall dust and the like. However, these vacuums come with variable speeds so you can regulate how much suction they provide.


So how does a vacuum work? The answer: much like a straw. Vacuums began as a luxury household appliance only for the affluent or top hotels. However, they quickly morphed into something else. Vacuums are now one of the most popular household appliances and they are even the most common electric cleaning appliances used in America. Their popularity is not without reason. Vacuums pick up all the evidence of our day-to-day spills, drops, meals, and festivities. They pick up the dirt too small for the eyes to see and keep our homes clean.

Although vacuums have become more sophisticated, sleeker, and easier to maneuver with the passing years and technological developments, they are still very much the same. As mentioned, these wonder machines work much like a straw. They use high and low-pressure systems created by a high-speed fan to create suction to lift dirt, dust, and debris. Quality vacuums usually have smaller intake ports, high-speed fans, multifaceted filtration system, and good air flow. We hope that this brief overview answered the question, “How does a vacuum work?” and gave you insight into what makes a good vacuum.