1. Product Overview
The Hilti 203857 HEPA Fleece Bags are designed for use with the Hilti VC 40-U Vacuum Cleaner. These high-efficiency bags are crucial for effective wet and dry dust collection, ensuring optimal performance and maintaining the HEPA filtration capabilities of your vacuum system. This pack contains 5 fleece bags.

Figure 1: Front view of the Hilti HEPA Fleece Bag, showing the main body and the black connection collar with "VC 40" printed on it.
2. Installation (Setup)
Proper installation of the fleece bag is essential for efficient dust collection and to prevent damage to your vacuum cleaner. Follow these steps:
- Prepare the Vacuum: Ensure the Hilti VC 40-U vacuum cleaner is unplugged from the power source before opening the dust container.
- Open Dust Container: Release the latches on the vacuum cleaner to open and remove the top section or access the dust container compartment.
- Remove Old Bag (if applicable): If an old bag is present, carefully remove it, ensuring to seal the opening if possible to contain dust. Dispose of the old bag responsibly.
- Insert New Bag: Take a new Hilti HEPA Fleece Bag. Locate the opening collar on the bag. Align this collar with the bag inlet port inside the vacuum's dust container.
- Secure the Bag: Push the bag collar firmly onto the inlet port until it is securely seated. Ensure there are no gaps around the collar that could allow dust to escape into the main vacuum chamber. The bag should unfold neatly within the container.
- Close Vacuum: Close the dust container lid and secure the latches firmly.

Figure 2: Close-up view of the bag's connection collar, illustrating the mechanism for attaching to the vacuum's inlet port.
3. Operation and Usage
Once the fleece bag is correctly installed, the Hilti VC 40-U vacuum cleaner is ready for operation. The bag functions as the primary collection unit for dust and debris, protecting the vacuum's internal components and maintaining air quality.
- Regular Use: Operate your vacuum cleaner as per its own instruction manual for general cleaning and dust extraction tasks.
- Dust Collection: The fleece bag will efficiently capture fine dust particles, including those requiring HEPA filtration.
- Wet Collection: These fleece bags are suitable for both wet and dry dust collection, offering versatility in various applications.
4. Maintenance (Bag Replacement)
To ensure continuous optimal performance of your Hilti VC 40-U vacuum and effective dust collection, the fleece bag must be replaced regularly.
- When to Replace: Replace the bag when the vacuum's suction power noticeably decreases, or when the "bag full" indicator (if present on your vacuum model) illuminates. For heavy use, consider more frequent replacement.
- Replacement Procedure: Follow the same steps as outlined in the "Installation" section (Section 2) to remove the old bag and install a new one. Always ensure the vacuum is unplugged before performing maintenance.
- Disposal: Dispose of used bags according to local waste disposal regulations.
5. Troubleshooting
If you experience issues with dust collection, consider the following common solutions related to the fleece bags:
| Problem | Possible Cause | Solution |
|---|---|---|
| Reduced Suction Power | Bag is full or clogged. | Replace the fleece bag with a new one. |
| Dust Escaping Vacuum | Bag not properly seated or damaged. | Ensure the bag collar is securely attached to the inlet port. Inspect the bag for tears or holes; replace if damaged. |
6. Specifications
- Model Number: 203857
- Material: Fleece
- Color: White
- Item Weight: Approximately 1.35 pounds (for the pack)
- Product Dimensions: Approximately 18 x 11 x 2.5 inches (packaging)
- Quantity: Pack of 5 bags
- Special Feature: Lightweight, suitable for wet & dry dust collection
- Compatible Devices: Hilti VC 40-U Vacuum Cleaner
7. Warranty and Support
For specific warranty information regarding Hilti products, please refer to the documentation provided with your Hilti VC 40-U vacuum cleaner or visit the official Hilti website. These fleece bags are consumable items designed for replacement.
For technical support, product inquiries, or to locate authorized Hilti service centers, please contact Hilti customer service directly or visit their official website:
- Hilti Official Website: www.hilti.com
- Customer Service: Refer to the Hilti website for regional contact information.





