How to Clean a Festool CT 26 Dust Extractor
A Festool CT 26 has several parts that are easily confused: the collection bag, the main filter and the optional wet-use filter do different jobs. Cleaning the extractor should preserve that separation instead of washing everything that looks dusty. This guide covers the CT 26 E HEPA described in Festool's operating instructions, focusing on routine workshop maintenance and the change between dry and wet collection. Newer EI and AUTOCLEAN variants must follow their own manuals where their controls or filters differ.
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Primary reference: Festool CT 26 E HEPA original operating instructions, dealer-hosted PDF. Always check the manual for your exact model.
Quick reference
- Power
- Unplug before opening; isolate connected tools
- Collection bag
- Replace the standard disposable bag when needed
- Main filter
- Correct rated replacement; no wash-and-reuse shortcut
- After liquids
- Clean sensors, dry container and restore dry filters
- Variant check
- CT 26 E HEPA is not every EI or AUTOCLEAN model
What you will need
- A replacement bag approved for your CT 26 configuration
- The correct replacement main filter if inspection shows it is needed
- Soft cloths and a suitable container for collected waste
- Dust protection appropriate to the collected material
- The CT 26 E HEPA operating manual
Step-by-step instructions
Step 1: Identify the extractor and the material it collected
Read the model label and identify whether the last job involved dry debris or liquid. Follow the material's handling and disposal requirements before opening the container; do not shake unknown construction dust into the room. This routine guide is not a hazardous-material cleanup procedure. Switch the extractor off, unplug its supply and disconnect a tool from its appliance socket. Automatic tool activation is another reason not to rely on an idle motor as proof that the machine is isolated. Apply the brake and work with the container stable.
Step 2: Remove the bag without creating a dust cloud
Release the locking clips and lift off the upper section, placing it securely where the filter will not be knocked against a dirty bench. Remove the used bag using its closure arrangement and the diagrams in the Festool CT 26 E HEPA manual (manufacturer document hosted by a dealer). Handle it gently instead of compressing it to make room for more dust. An ordinary disposable filter bag should be replaced when full or damaged; do not assume the SELFCLEAN name makes it washable or the same as a dedicated reusable bag.
Step 3: Clean the container and inspect its sealing surfaces
With the collection bag removed, clean residue from the container according to what was collected, controlling dust rather than brushing it into the air. Use a soft cloth on accessible surfaces and inspect the rim and inlet where the upper section and bag must seat. Keep the electrical upper section out of wash water. If damp wiping is needed for ordinary nonhazardous residue, allow the container to dry before installing a dry-use bag. A clump on a sealing edge or a trapped piece of bag can matter more to correct assembly than cosmetic dust on the outer case.
Step 4: Inspect the main filter and replace it when required
The CT 26 E HEPA instructions describe removal and replacement of the main filter, not washing it back into service. With power disconnected, turn the removed upper section so the filter faces upward, release the lever and retainer as illustrated, and fit the correct replacement when necessary. Control released dust throughout; the manual describes lightly moistening the filter's surface before removal to limit dust, which is not a washing method for reuse. Do not scrub the pleats, blow them out with compressed air or run the extractor without its required filter installed.
Step 5: Match the filter rating, not just its physical shape
Check the part designation and filtration requirement when buying a replacement. Festool's 496170 standard filter information explicitly says it is not a HEPA filter and must not be used where HEPA filtration is required. A part fitting the same container does not make its performance equivalent. Likewise, an AUTOCLEAN filter or a wet filter should not be selected solely because CT 26 appears somewhere in a listing. Match the machine variant, intended material and original specification before closing the filter retainer.
Step 6: Use the separate wet-collection cleanup route
Before approved liquid collection, remove the collection bag and configure the extractor with the specified wet filter rather than using the dry main filter. Never collect combustible liquids or hot material. After wet use, empty the container and clean the fill-level sensors with a soft cloth, checking for damage. Stop immediately if foam or liquid escapes during operation. Before returning to dry work, remove the wet filter and restore the correct dry main filter and bag, with the container dry. Do not assume automatic level shutoff removes the need to clean the sensors.
Step 7: Reassemble and check the complete airflow path
Fit a new bag firmly onto the inlet and make sure it is not pinched between the upper and lower sections. Secure the main-filter retainer, replace the top and close the locking clips. Inspect the hose and cuffs for a blockage or poor connection before blaming every suction loss on the filter. Reconnect only after the configuration is complete, then check normal operation. Festool also calls for periodic safety and dust-system inspection; routine wiping does not replace that. Store the clean extractor indoors and dry, with its cord and hose secured without sharp bends.
Specific cleaning questions
Open a question for a concise answer about stains, odors, safety, frequency, and troubleshooting.