Venta Gearbox Repair

This is for Venta humidifier models LW44 and LW45, possibly for other models but I have not tested it on any other models.

An old (and dirty) gearbox slows down the propeller and will eventually result in multiple problems: slow startup, ticking, skipping etc. Remove the gearbox from the humidifer and open it (see photos 1-3). Be careful when removing the caps, be gentle, you do not want to break them. Once the gearbox is open, remove all parts and clean them. Soaking them in water with soap works very well. Use an old toothbrush to remove all the dirt from each part.

The parts that usually show the most wear and tear are the little black "thumbs" that move the disk. It is a good idea to replace them. They come in a left and a right version, just make sure that the spring side is always pointing to the center of the gearbox frame and that the thick area of the parts are pointing to each other.

Assemble the gearbox in steps (photo 4-5) and make sure that everything moves extremely smooth after each step. Then close the gearbox (photo 6) and add both caps. If you damaged a cap on disassembly, print a new one.

You can try to lubricate the box with a water resistant silicon lubricant (spray) but it is not really necessary.

Last but not least, I designed clips (photo 8) that you can use to hold your gearbox in place (prevents it from tilting). You will need two of them, one one each side of the gearbox. They snap easily in place. The arrow will remind you how to remove them.

Update (12/4/23): I added updated "thumbs", one set for the LW40/45 and one set for the LW25.

Update (12/10/23): Added a gear, print as is, with supports on base plate only. You get the best results if you print this component in nylon.

If your print the gear, use a 0.25mm nozzle. Also, it is important that the ring that makes contact with the thumb is as smooth as possible. I use a small file to make them as smooth as can be. Makes a big difference.

Update(1/24/24): Added V3 of the cap, less friction, better fit.

Update (1/24/25): Added V9 versions of the thumbs, both for LW4X and for LW25. Added cap version 4. Added gear version 2.8.

I noticed that thumbs printed in ABS perform better (more quiet) than thumbs printed in PETG.

Update (1/3/2026): Added V5 of the cap, removed some old versions of thumbs and cap.