CT 33 vacuum stops after several seconds

mbs

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Joined
Oct 16, 2012
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Anyone know why the vacuum start on manual or auto mode but stops after approx 5 seconds on high speed and 20 seconds on low speed?  It won't restart without resting for approx 4 minutes.  The vacuum never got warm and the circuit breaker is closed but it acts like a thermal switch is getting tripped.

Thanks,

MBS
 
Sounds to me like a heat problem. Even if the vac doesn't get hot on the outside, the motor could locally become very hot. There's a heat sensor inside the vac that turns the vac off if it becomes too hot, and then after a cool down period, you can restart the vac again.

As this happens constantly, there seems to be a problem with the motor. If it overheats this quickly, it is probably broken. I would take the vac apart and check each part if it works or not. If this is not your cup of tea, it is time to contact Festool service and let them sort it out. But don't be surprised at a hefty repair fee.

In the short time the vac does work, does it develop good suction?
 
The vac has great suction.  It doesn't act like anything is wrong with it except it shuts down.

 
    That has got to be something with heat and the electronics / switch / etc.  Call Festool. It cold be a send in  , which could be expensive, or it could be a very simple switch swap out that you can do your self. 

Seth
 
I called Festool.  The representative was very nice but he couldn't offer any advice.  He suggested I send it in for repair.  I think I will try to figure it out because I believe the shipping and repair cost will be $$$.
 
mbs said:
I called Festool.  The representative was very nice but he couldn't offer any advice.  He suggested I send it in for repair.  I think I will try to figure it out because I believe the shipping and repair cost will be $$$.

It is useless now, so you'll have to weigh up the shipping cost as I doubt there are other people that service them.
Or bin it.
 
Shipping cost+labour+parts is going to be very costly, it is probably cheaper to find a used CT26 or more cost effective to buy a new one.
 
Please do a video of opening it up and trouble shooting. It could be informative and/or entertaining.

The problem could be that a small electrical component has gone bad and it may be impractical to figure out how to repair it.
 
Hi [member=16804]mbs[/member]

Forgive me stating the obvious but as I seem to have the odd "senior moment" and forget the simplest of things myself....

Does it still do it with the dust bag, filter and hose all removed ?

Peter
 
What about the turbine's brushes ?  Are they worn out?

That'd be an easy and inexpensive repair for you to DIY.
 
Peter Parfitt said:
Hi [member=16804]mbs[/member]

Forgive me stating the obvious but as I seem to have the odd "senior moment" and forget the simplest of things myself....

Does it still do it with the dust bag, filter and hose all removed ?

Peter

Yes, it still shuts down with everything removed.  When I switch the motor back on I can hear the capacitor? energize but the motor doesn't start.  I set the switch to off then after approx 5 seconds the motor will start.  With each successive start/stop the motor will run a shorter period of time and take longer before resets. 

It acts like a thermal issue to me.
 
antss said:
What about the turbine's brushes ?  Are they worn out?

That'd be an easy and inexpensive repair for you to DIY.

I don't know much about motors.  Will brushes cause the behavior that I'm describing?

 
mbs said:
Peter Parfitt said:
Hi [member=16804]mbs[/member]

Forgive me stating the obvious but as I seem to have the odd "senior moment" and forget the simplest of things myself....

Does it still do it with the dust bag, filter and hose all removed ?

Peter

Yes, it still shuts down with everything removed.  When I switch the motor back on I can hear the capacitor? energize but the motor doesn't start.  I set the switch to off then after approx 5 seconds the motor will start.  With each successive start/stop the motor will run a shorter period of time and take longer before resets. 

It acts like a thermal issue to me.

Hi [member=16804]mbs[/member]

It is unlikely to be the brushes. One final thought is to look to see if there is a physical obstruction in the fan or the internal path for both fresh air and dirty air. If there are moving parts that should spin check to see that they do spin freely - they might have some reluctance if they are directly connected to a motor but should still move without grinding. If all that fails....

Then it is beyond my pay grade and would be best looked at by Festool.

Peter
 
Peter Parfitt said:
mbs said:
Peter Parfitt said:
Hi [member=16804]mbs[/member]

Forgive me stating the obvious but as I seem to have the odd "senior moment" and forget the simplest of things myself....

Does it still do it with the dust bag, filter and hose all removed ?

Peter

Yes, it still shuts down with everything removed.  When I switch the motor back on I can hear the capacitor? energize but the motor doesn't start.  I set the switch to off then after approx 5 seconds the motor will start.  With each successive start/stop the motor will run a shorter period of time and take longer before resets. 

It acts like a thermal issue to me.

Hi [member=16804]mbs[/member]

It is unlikely to be the brushes. One final thought is to look to see if there is a physical obstruction in the fan or the internal path for both fresh air and dirty air. If there are moving parts that should spin check to see that they do spin freely - they might have some reluctance if they are directly connected to a motor but should still move without grinding. If all that fails....

Then it is beyond my pay grade and would be best looked at by Festool.

Peter

Hey Peter,  I can't find any  sign of obstruction.  The motor spins down slowly without any sign of obstruction.

thanks
 
Hi mbs

Then it is well beyond the capability of my little grey cells. I am sorry that it really does look as though you have the bite the (Festool) bullet.

Good luck - I hope that it is not too expensive.

Peter
 
My best guess is brushes or commutator.  The 'humming' could be due to weak current to the armature.
 
[member=11196]Peter Parfitt[/member] - why are you dismissing the brush possibility ?

Some tools have shut down circuits when the brushes go worn to avoid damaging the armature.

Even if it's not that , they are prob . pretty worn on a 7+ year old vacuum.

That's a cheaper trouble shoot than the control board , which is a very likely culprit too.
 
First time poster of photo here, let us hope it works.  This (I hope) is a photo of a CT 22/33 motor taken circa 2010.  The green circles on the motor indicate the brush locations.  The brushes are very large compared to the brushes in other Festools, but they do wear out.  As other brushes toward the end of their life they may lose some of their effectiveness because of age, dirt, or both.  The may fail to advance to the armature as necessary.  Shake it around a bit and see if the brushes advance, starting the motor.
 

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Hi [member=727]antss[/member]

I did not dismiss it but do think it unlikely.

My reason is that the start-up and then shutting down sounds too regular or repeatable. In my experience with worn brushes it is more sporadic.

I also came clean and said that from everything presented that it is beyond me having discounted a mechanical interference and my feeling that it not the brushes. The electronics of the CTs are a complete unknown area for me.

Lets hope that we are told the real cause at some point.

Peter
 
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