Vacuuming your home might feel like a chore. But at least by the end of it, you can sit back and relax in a cleaner, fresh-smelling environment, right?
Well, most of the time, that’s true. But sometimes, even the best vacuum cleaner can surprise you with an unpleasant aroma. Worse still, you might unwittingly spread it across your floors, leaving you worse off than when you started.
“We know that overtime unpleasant smells can build up in vacuums, particularly if you are a household with pets,” says Tracey Scully, UK managing director at SharkNinja. “But a smelly vacuum doesn’t mean that your home is unclean: it’s just that regular pick up of hair, dust and dander can cause bad odors to build up inside it.”
In this article, we’ll draw on some expert advice on what causes vacuum cleaners to smell, and how to avoid it. These are all solutions you can try yourself, at home – if none of these things work, professional servicing may be needed.
Cause #1: Full bin
The most common reason a vacuum starts to smell, says Sophie Lane, product training manager at Miele, is that you don’t empty your bag or bin regularly. “If the dirt and debris inside isn’t removed in a timely fashion, it’ll linger over time, breaking down and causing unpleasant smells,” she explains. That can be especially true if you’re collecting a lot of pet hair.
Solution: Empty the bin regularly
To prevent this happening, Scully recommends you empty your vacuum after every use. “This stops dirt from sitting there for too long and creating a smell,” she explains.
If you don’t want to be bothered with that, some new vacuums come with a self-empty base, or you could opt for a bagged vacuum – but we’ll get into that in more detail in the Maybe you just need a new vacuum section.
Cause #2: Clogged filter
You also need to pay attention to your vacuum’s filters. “These trap dust and particles, but over time these can get clogged or dirty,” Lane points out. “If they’re not cleaned or replaced regularly, they can develop odors. Especially if they trap allergens, mold spores or fine dust.”
Solution: Clean or replace the filters
Dyson engineer, Geli Lee recommend you clean the filters once a month. If you have one of the best Dyson vacuums, the LCD screen will pop up with a reminder when it’s time to clean your filter.
Owning pets means you’ll want to clean or replace your vacuum’s filters especially regularly; not only will this prevent odors, but it also ensures your vacuum continues to perform at its best.
Geli also cautions that odors in vacuum cleaners can be caused due to bacteria build-up during the drying process. “To avoid that, try speeding up the drying by placing the washed filter in a well-ventilated area or near an open window. Shaking and rotating it helps too.” (Here’s more on how to clean a Dyson cordless vacuum.)
After all that, if the smell persists, it may be time to replace the filter. In short, regular care and filter replacement are key to keeping your vacuum odor-free.
Cause #3: Trapped dirt or pet hair
Outside of the bin and filter, there are a number of places where pet hair and dirt can collect and lead to a build-up of odors. Here’s a quick run-through of what to do to get your vacuum clean:
Solution: Detangle the brushroll
Over time, hair, string and debris can wrap around the brushroll, preventing it from spinning properly and causing buildup that contributes to both bad odors and reduced suction.
To clean your brushroll, start by unplugging the vacuum and removing the brushroll according to your vacuum’s manual. Use scissors or a seam ripper to carefully cut away any tangled hair or threads, then wipe down the roll with a damp cloth to remove any lingering dust.
Some soft brushrolls – like the Fluffy Floorhead roller on newer Dyson vacuums – are designed to be removed and washed completely. Do double-check the user manual before doing this though; it’s not suitable for all floorheads.
Solution: Clean the hose and attachments
Detach the hose and inspect it for blockages by running a broom handle or flexible brush through it to dislodge any trapped debris. You can also rinse the hose with warm soapy water, although you’ll need to make sure it’s thoroughly dried before reattaching it.
The smell might also be coming from attachments such as the crevice tool and dusting brush. These can be washed in warm, soapy water to remove any dirt buildup. Again just sure they’re fully dry before using them again.
Solution: Try baking soda
Unfortunately, with the most persistent smells, even if you clean your vacuum from top to bottom they may still stick around stubbornly. In which case, sprinkling baking soda (US) / bicarbonate of soda (UK) on the floor and vacuuming it up can help absorb lingering odors in the machine. This is a natural deodorizer, and it’s a simple way to neutralize smells trapped in the vacuum.
Cause #3: Mold or mildew
A further danger Lane identifies is when a vacuum is used to deal with spills, or damp dirt. “Moisture inside the vacuum can lead to mold or mildew growth,” she explains. “This is a common issue in vacuums used to clean damp areas or when wet items are accidentally sucked up.”
For pet owners, vacuum smells are often intensified. “If you have pets, their hair can get trapped in the vacuum cleaner, leading to a strong odor,” Lane continues. “Wet pet hair, in particular, can create an environment conducive to mold or mildew growth within the vacuum.”
Solution: Detergent or vinegar solution
If you suspect that mold or mildew is causing the smell, she recommends cleaning affected parts with a mild detergent or vinegar solution. Again, make sure the vacuum is completely dry before using it again.
Prevention is better than cure, though. “So I’d recommend you avoid cleaning up wet messes with a standard vacuum, unless your vacuum has a ‘wet and dry’ feature,” says Scully. (For more on that, read our article What does a wet and dry vacuum cleaner do? or head to our guide to the best wet-and-dry vacuums).
Cause #4: Mechanical issue (burning smell)
So far we’ve focused on smells that are merely unpleasant. But a burning smell isn’t just unpleasant: it’s a sure sign of danger. Here are the key things to do:
- Turn it off immediately, and unplug it if it’s corded
- Check for blockages in the hose, brushroll, bin inlet and filter
- Inspect the belt for signs of wear, breakage or misalignment
- Examine the motor (or get a professional to do so)
- Get the vacuum serviced
Cause #5: You just need a new vacuum
While a smell on its own shouldn’t require you to replace the whole machine, if your vacuum was already coming to the end of its life, there are certain features and add-ons to look for in a new machine that can help prevent smells.
Bagged vacuums
If you know you’re regularly dealing with dust and dirt that’s prone to odors (e.g. if it has a lot of pet hair in), it’s worth thinking about whether you go for a bagged or bagless vacuum.
“While bagless vacuums can be messy to empty, bagged vacuums allow for easy, clean and hygienic emptying, containing dust, dirt and allergens, and often providing a larger capacity for up to a month’s worth of cleaning,” says Teya Field, product manager for Henry. “Bagged vacuums also protect the vacuum’s motor from exposure to dust, prolonging machine performance and life.” (For more on this, see our article exploring why a bagged vacuum might be a good choice, or our bagged vs bagless vacuum comparison).
As well as being useful for containing smells, bagged vacuums can be a good choice for those with allergies, because there’s less chance for allergens to escape back into the air when emptying the bin. “When it comes to pet owners and those of us susceptible to allergens, bagged vacuums are perfect,” believes Teya.
Auto-empty base
The level up from that is to go for a vacuum with an auto-empty base. These are still fairly rare on the market, but the newest and best Shark vacuums, like the Shark Detect Pro Cordless Vacuum and PowerDetect cordless vacuum all come with a compatible auto-empty dock.
When you sit the vacuum on the dock to charge, it’ll suck all the dust from the bin, via a sealed system, into a much larger bag in the base. This also means you don’t have to remember to manually empty the bin after each use.
Special filters
Many of the best vacuums for pet hair come with advanced filtration systems, which trap even the smallest particles and allergens, and help control bad smells by filtering the air as it passes through the machine.
“For those looking to reduce lingering pet smells, we’d recommend vacuums with a charcoal-activated filter,” says Teya. Charcoal filters absorb and neutralize smells (similar to the odor-busting features found in some of the best air purifiers); they can be found in the Henry Pet and Harry models, as well as in many Miele vacuums.
Scent pods / deodorizing pucks
Beyond odor-absorbing filters, some vacuum brands offer separate solutions to potential bad smells. Some Henry vacuums have the option for scent pods to freshen your home as you clean – for example, the cordless Henry Quick range.
Meanwhile, Shark vacuum cleaners have recently introduced a special puck designed to neutralize bad smells directly at the source. Its Odor Neutralizer technology (known as Anti-Odour technology in the UK) is designed specifically to tackle potential odors in the dust cup. Read more about these in our guide to the most popular Shark vacuum technologies.