Fixing a CTL26E that wouldn't start

[tommag]

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

 

[tommag]

This is the repair picture

 

[tommag]

And the measurement pictures

 

[Frank-Jan]

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.

 

[madcow]

I posted this in another thread, but I’m also adding it here in case one of you who seems to have had similar problems sees this. I’m not sure what voltage I should see at the motor or at the 2 pin connector (should be the same I think).

I know this post is old but I’ll give it a try. I have a CT 26 E that I recently bought used. They were selling it for parts because it only worked intermittently. I plugged it in and it worked. I decided to take it apart and have a look inside to see if there were any lose connections or if it was really dirty.

I cleaned it all out and noticed that the brushes were about half worn. I ordered new brushes and waited. I replaced the brushes and now it won’t power up at all. I checked the voltage at the motor and it’s only getting less than 40V. I should note that I live in the Us and therefore have a 120V model. I checked the voltage at the two pin connector on the PCB under the control panel and there is only like 4 V going on those pins in both auto and manual. I’m not sure how much voltage should be going there because those wires are fairly thin and I can’t find any schematics. I don’t want to pay $170 for a new PCB because if it isn’t the problem, Festool won’t let me replace it.

I’d appreciate any help anyone can lend me. Thanks.