Water Filter for Fireplace Ash Vacuum Cleaner




I purchased an ash vacuum cleaner for my fireplace a few years ago. It's purpose is to vacuum the extinguished ash and small unburned charcoal pieces from the burning chamber.

It works like a charm for the first 1-2 minutes but then the internal filter gets clogged by fine ash particles and it is useless. Also it is torturous to clean the vacuum filter, the bucket and the hose after all that clogging.

So I didn't use it much except at the winter season finale, when I wanted to clean the burning chamber thoroughly.

Until now.

Step 1: Eureka!

The eureka moment was when I remembered the principle of operation of another vacuum cleaner we had stored at the basement. It is the model DS 5500 made by Karcher. It uses a water filter as its primary dust trapping mechanism along with some paper ones. We didn't use it much because of the very expensive proprietary filters so we invested in a Miele model instead that uses dust bags.

Step 2: Gather Some Stuff

For this instructable you will need :

  • an empty bucket with its lid (mine contained 15 kg of paint)
  • an ash vacuum cleaner
  • a pencil
  • a sharp knife
  • some spare vacuum tube
  • hot glue gun with hot glue sticks or silicone caulk sealant

Step 3: Prepare the Lid

Take the metallic orifice of the vacuum cleaner and make two tracings diametrically opposite using your pencil.

Cut along those tracings with a sharp knife. You will create two openings on the lid.

Step 4: Connect the Hoses

Connect the metallic orifice in one hole and the spare tubing in the other. If you cut the holes right, they should fit snugly.

Apply some hot glue to fasten and seal them on the lid. Alternatively you can use silicone caulk but you will have to wait for it to set a lot longer than hot glue.

Note that the plastic tube will have to be submerged in the water. The ending of it should be a few cm higher from the bottom of the bucket and not in direct contact with it.

Step 5: Add Water to the Bucket

Add some water to the bucket. Do not overfill the bucket. Below the middle is sufficient.

Then close the lid. I secured the lid with a few blows from a wooden hammer.

Step 6: Let's Experiment!

Connect the vacuum cleaner's hose to the metallic orifice.

Then plug the vacuum to the wall socket and turn it on.

P.S. I am terrible at filming and even more terrible at filming with one hand. My apologies. At the end the lid was stuck from the hammer blows so I had to let the camera down to use both hands.

Step 7: Results

As you can see the filter has no problem filtering all the ash and debris that falls in.

The bucket of the vacuum cleaner on the other hand is clean and dry.

After you finish vacuuming you can take the bucket outside and dispose its contents properly.

Don't forget to rinse the bucket with water.

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    8 Discussions


    1 year ago

    not bad,you better do some small holes at the end of the plunger to reduce bubbling and improve effectiveness.


    2 years ago

    This looks good but ... if it is so effective, wouldn't it be possible to use any form of vacuum cleaner, not just a fireplace ash cleaner?

    I clean my fire by hand, using brushes. My wet/dry vacuum cleaner just sits there, watching me and looking very lazy ;-)

    I'd like to put it to work!

    1 reply

    Reply 2 years ago

    Theoretically any vacuum cleaner will do. Since I had a dedicated ash cleaner I messed around with that instead of the regular vacuum cleaner.


    2 years ago

    That would be some extremely caustic water. A lot of lye is leached from ash with water. Make sure you dispose of it properly.

    This makes a lot of sense. Personally, I would put a baffle on the out-line of the bucket to prevent water from being sucked into the vac (unless you have a wet-dry vac that is). Alternatively, an additional, empty bucket setup the same way would perform the same task.

    2 replies

    Reply 2 years ago

    By baffle you mean something like a metallic mesh for any water vapour to condense?


    Reply 2 years ago

    I mean a board or piece of sheet metal to block water from entering the vacuum intake. It would have to get around the baffle to enter the vacuum hose.


    2 years ago

    Almost the same principal as a hookah, and a great inexpensive solution, nice work!

    1 reply