I ordered a 6 liter Vevor ultrasonic cleaner to clean some old clock parts. I used it right after I got it to make sure it worked and it seemed to work great. I got it out again about a month later to do a new clock I got and it worked for the first 15 minute session. I had to flip the movement over to get the rest of the unit done as it didn't completely submerge in the fluid. Turned the timer back on and.....nothing. The unit still had power and it would still heat, but the transducers wouldn't start up again. I submitted a ticket to Vevor on it. Of course they require you to upload a video for some reason in (only 2 specific file types). I didn't have it nor would my phone output that file type. I just downloaded a stock video of a forest in the required format and added it to my support ticked so it would move forward. Their response was that after they looked at my video (really?!!) they determined it was the circuit board and they were sending me another. It seems I have to tear the machine apart and fix it myself! The average person would not even attempt this, as the unit plugs in and is usually running in your house. Why not play with it, not knowing what you are doing, and burn down your house after you attempt to re-build the unit?? I have some experience with repairing computers, so I might have a chance to fix it, and not start a fire afterwards. Beware the Vevor ultrasonic units!!!