Vacuum doesn't work on bare floors!

The answer is simple...vacuums with filters allow air and anything finer than the size of the filter holes to pass through...if you hold a light over your bag and turn the vac on, you will see an explosion of fine dust coming from the bag...Vacs work on airflow, so the less air flowing through the bag, the less dirt you pick up...clogged bag = no airflow=no cleaning. Bagless vacs should have the filters cleaned after every use, and the canister emptied and washed. Buy a Rainbow to eliminate these problems.

Go to a vacuum sales and repair depot. I was at one yesterday. they have about anything you need

Dirt Devil Parts

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Dirt DevilNo promo code required. ... most popular: Bags: Belts: Filters: Cleaning Solutions: Filters, F1-F85: Filters, Adapters: Filters, ... vacuum cleaner: Attachments & Tools: Brushrolls, Hand Vacs: Brushrolls, Uprights ... Handheld Steam Cleaners.

Type G (10 Pack) - 3010348001 - Dirt Devil

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Dirt DevilGenuine Type G bags. Fits all hand vac models equipped with the paper bag adapter. Includes ... The Handheld Vacuum That Picks Up Where Others Leave Off ...

Ultra Corded Bagged Handheld Vacuum - Dirt Devil

Pull out on the clips on each side while pushing on the red part in the center of the clips. Pull black bottom away from the red top while pulling out on the clips.

Do you mean the beater bar stops turning and then it doesn't vacuum?
Or it shuts off when you jam it full of carpet? Read the below manual:
http://www.sebo.us/pdfs/website_owners_manualsPDFs/AIRBELT%20K%20Manual.pdf

Cleaning filters on a bagless vacuum helps but filters should be replaced frequently, as often as every 3 to 6 months on some vacuums. Foam filters aren't as critical to replace because the pores are very large (which also means they don't filter out the small particles) so they don't clog as easily but paper filters have much tighter pores which become clogged and restrict the airflow. Cleaning paper style filters with water which can pack the fine dust into the pores clogging the airflow even more.
I recommend replacing filters st least onceor twice per year and cleaning them after each use for best performance and longer vacuum life. Blowing the dust out with an air compressor is my preferred method.
Changing filters frequently on a bagged vacuum isn't as critical because the bag collects most of the fine dust, dirt and gunk. The surface area of a bag is much greater than that of a filter so a bag is less likely to get clogged than a filter. Most homeowners change the bag once per month which keeps the air flowing smoothly.

I'm not sure about a 3 month old vac, I'd probably go the warranty route. However, for the older vacs thy start getting false positives. The sensor is simply a microphone hooked to a computer chip detecting sounds of dirt entering the bag.
To rig it to start working, you'll need to remove the tool accessory tray and elbow that enters the back of the vac, and attached to the bag. This will reveal the microphone at the elbow, and wire that runs into the bottom area of the vac. When on, a large amount of air comes from the bottom screw and area where the wires enter. My fix was to clean up the microphone contact points a little bit with a screwdriver, and then leave the vac running while putting in dampering in the hole at the bottom, and around the back of the elbow. Cotton balls and electrical tape at the bottom hole, and napkins around the outside of the elbow (wedged between the back of the vac assembly and elbow did the trick). The schematic for the vac is here: http<colon>//www<dot>vacsrus<dot>com/CartGenie/pg_U6485900<dot>asp
Look for micrphone.

hi from uk may i suggest you remove cover and the new dust collection bag then if you look in the bag compartment there is a gauze filter fitted usually grey in colour ? at opposite end of compartment where bag connects this gauze filter is the outlet from bag compartment that the air exhales when vac is operating ie as vac **** up dust into bag the bag has microscopic holes that allow sucked up air and dust to collect but keeps dust from passing into bag chamber but allows air to escape thro holes and so enter bag chamber then escapes via the gauze filter to outside of vac hope you follow this ?? now if this filter is blocked/never been cleaned/changed ? then the symptoms of indicator bag full light will come on you can remove and wash filter if it is gauze typ? dry and refit then try vacuuming ? or replace filter they are not expensive usually in pack of 3 in uk DO NOT RUN VAC WITHOUT THIS FILTER FITTED ! or you will have some dust in the room ? hope this helps?

It's clogged!
Many so-called "environmentally friendly" vacuum cleaners have multiple stage filters; the usual configuration is a standard filter followed by a HEPA filter or equivalent. Standard filters can be a paper bag or a bagless, removable container.
From time to time, the secondary filter will get clogged, so it doesn't matter whether you change the bag or empty the container, performance will not improve.
If you have access to compressed air, try removing the secondary filter and blowing it clean with a high pressure air nozzle. If that doesn't work, check the hose to make sure it's clear. If you are using a rug beater attachment, make sure it has not clogged at its inlet.

Hi there SmartAlec from NelsonVacuums.com.au here. I am a nilfisk vacuum agent and although i havent actually worked on one exactly the same as yours there are no Nilfisk with any kind of washable filters at all. I think you will have to replace it. If you are in Australia i can check out the cost of replacement filters for you just drop me an email with the exact model number.
Hope this helps.
Happy Vacuuming :)