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Author Topic: Fixing a CTL26E that wouldn't start  (Read 535 times)

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Offline tommag

  • Posts: 3
Fixing a CTL26E that wouldn't start
« on: November 28, 2022, 04:05 AM »
Hello everyone,

I've spent some time reading the topics in this forum and it helped me diagnose the problem so I just wanted to share here how I fixed a 2nd hand CTL26E vacuum cleaner (sold as defective).

When i got it, it worked for a few minutes, then it would start and stop immediately after half a second just as in this post : Vacuumcleaner malfunctioning CTM 36 E AC HD with movie

Here is the list of what I tried with no luck :
  • changed the power cord
  • checked the motor brushes
  • checked the motor connection to the electronics board (it seemed a bit loose)
  • bypassed the main switch
  • tried to connect the motor directly to mains to make sure the motor was OK (it was)
  • checked the thermal sensor (it was ~80ohms at 15°C and resistance decreased when heated up so it looked reasonable)
  • checked the water full sensor (disconnected from the board and checked that there was no resistance between both "legs")

In the end it really looked like a sensor issue so I kept poking around the thermal and water sensor. What surprised me was that the water sensor input was electrically floating : there was no consistent reading of resistance between the two pins nor between the input and what I identified as +5V on the board - check pictures, the resistance was around 20k but not stable.

So what did the trick was to attach a 10k resistor between the input pin and the +5V pin. I ended up crimping a new connector for the water sensor to be able to attach it and have a clean repair. I haven't checked if the water sensor still works though.

Obviously, only attempt this if you are comfortable with electronics but I figured it could help someone, in the end it saved some electronics from the landfill and I got a cheap vacuum cleaner :)

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Offline tommag

  • Posts: 3
Re: Fixing a CTL26E that wouldn't start
« Reply #1 on: November 28, 2022, 04:08 AM »
This is the repair picture

Offline tommag

  • Posts: 3
Re: Fixing a CTL26E that wouldn't start
« Reply #2 on: November 28, 2022, 04:09 AM »
And the measurement pictures

Offline Frank-Jan

  • Posts: 1302
  • Dutch Canadian living in Belgium
Re: Fixing a CTL26E that wouldn't start
« Reply #3 on: November 28, 2022, 10:53 AM »
Thank you for sharing, this would have probably also been a possible fix for my old ct22, but I ended up giving it to a fellow contractor who had one with a cracked lower housing.