Shop vac blowing stuff out the back

Shop vac blowing stuff out the back. The main job of the shop vac is to suck the dust and clean the surface properly, but it is very frustrating to see your shop vacuum blowing dust and debris outside the dust container.

This mishap can happen to any shop vac machine due to various reasons; mostly, it happens that you forget to empty the dust container, and when it gets full, then it starts blowing stuff out the back.

So, the first thing to check whenever you face such trouble is the dust container and if it is full, empty it outside the home to start the work again.

If the dust container is empty and still stuff is coming out of the shop vac, then it might have the wrong settings due to a mistake, so reset the settings on the unit.

If you are here, then it means you are facing the same issue, so keep reading this guide to learn how to fix the shop vacuum-blowing stuff out the back.

Shop vac blowing stuff out the back

A shop vac is a convenient unit to clean the home, officer any place. Still, besides this, it’s also essential to keep maintaining it properly, like keep clearing the dust container, and don’t forget to attach a dust collection bag and check the wrong settings on the vacuum.

So, without further delay, let’s read all possible causes of the shop vacuum blowing dust out the back.

Dust container is full

dust container is full

When you start cleaning the home using a shop vacuum, it can quickly remove the dust from the floor.

However, it does not matter if you use which vacuum model; if the dust container becomes full of debris and mud, it will stop sucking further dust into the container.

It will also start to blow back the dust in the air when the suction tank becomes full.

So, whenever you see the dust blowing out of the tank during a cleaning session, then immediately turn off the unit and separate the dust collection tank to check whether it is full or empty.

Most probably, it is full, so carefully disconnect it from the unit and remove the dust, rotten leaves, and other debris outside the home in a safe place.

Reattach the dust collection bag with the shop vac and plug it in to start your work.

If you see the dust not coming out of the container, then you have to fix the issue, but if still, the vacuum is blowing out the debris outside in the air, then it means it has some other problem.

Incorrect settings

incorrect settings

If there is no problem with the dust container and it is empty, check the proper settings on the shop vacuum.

Some shop vacuums have a dual function; to suck in the dust or blow air out, so sometimes you fix the wrong settings on the unit, and the unit starts to pull out all the dust particles and debris.

So, check the settings on the vacuum and if the dual function is on, then switch it off and check if the unit is still blowing out the debris in the air.

Fix a collection bag

The collection bag is not fixed in the shop vac; cleaning the large debris material stops the dust particles that the filter can’t catch from blowing back. It also decreases the cleaning speed, and you have to run the machine for the long run for complete cleanliness.

So attach a dust collection bag with the vacuum cleaner. It is not difficult to detach the bag from the vacuum cleaner when you empty the debris gathered in the vacuum into the dust bin.

It is also very beneficial because the vacuum filter remains cleaner when the debris is directly confined in the collection bag.

Dirty filter

dirty filter

Another reason behind stuff coming out of the shop vac during the cleaning session is a dirty filter.

It depends upon usage, but if you do not maintain your cleaner by cleaning all its parts properly, you will face problems like this.

So, if you have not cleaned your vacuum filter, detach it from the unit and check the damage and holes in it.

If you locate any hole in the filter, then replace it with a new filter because it is not expensive and cheaply available on the market at different hardware stores.

You can also buy the new filter online from the Amazon service.

If there are no signs of damage on the dirty filter, then no need for its replacement, and clean the dust and debris stuck on it.

  • Turn off the shop vacuum cleaner and leave it for one hour to cool down; otherwise, it can burn your hands.
  • Wear safety gloves and glasses to protect yourself.
  • When the machine cools then, pull out its cover.
  • Separate the filter.
  • Turn out the vacuum filter in the dustbin and shake it well to remove all the dust and debris on its surface.
  • Rinse the filter in the sink but don’t use extra water pressure to clean it because if the water is coming at high pressure, it might damage the filter.
  • After cleaning all the dust from the filter, please leave it to air dry for 24 hours so that all the water should remove from it before you insert it into the shop vacuum again.
  • Let the filter dry before replacing it.
  • Remember, do not air dry it in direct sunshine because it will be dangerous for it, so leave it at a suitable place inside the room.
  • After drying out the filter, refix it with the vacuum cleaner.
  • Plug in the shop vacuum and start cleaning to check if the dust is still coming out or problem is solved.


The final thoughts on this article are if you are cleaning the room floor with a shop vac cleaner and suddenly you see a shop vac blowing stuff out the back, then immediately unplug the cleaner.

Check that the dust container bag is full; if it has no space for further dust and debris accumulation, empty it outside the home.

If you have not cleaned the dirty filter for a long time, rinse it with fresh water and attach it after a complete air drying.

If there is still no change after applying all the above tips, then your best bet is to hire a skillful professional to repair the faulty component of the shop vacuum.

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