Dyson dc30 switch suddenly not working properly

SOURCE: Overheating Dyson DC07

Many devices including this one have what's known as a thermal cut out.

It is there for obvious safety reasons and prevents the temperature in the locality of the cut out from exceeding a pre-defined value.
Some of them require you to press a reset button in order to switch the power back on and other types simply reconnect the electricity supply when the temperature returns to normal (safe) operating limits.
The Dyson DC07 has a thermal cut out located close to the motor and it is of the "self resetting" type.
If your vacuum cleaner switches off after a few minutes the most probable cause (there can be others) is the thermal cut out has operated.
The first and most important thing to do is to establish why it has operated.... If the airflow around the motor has become restricted then it will not be being sufficiently cooled and so it will have cut out correctly. However, thermal cut outs are often quite crude internally and it is not uncommon for them to start cutting out at too low a temperature. So...

Here's what to do...
(some tools may be required to complete the following so read the entire procedure before starting. Please note this is not an absolute guide if you need really foolproof step by step instructions... buy a manual! But this should help)

• remove and thoroughly empty the dust bin (do not put it back yet)
  
• remove and clean the drum filter to the right of the motor (right when looking at the front of the machine). (N.B. Never put this back if it is still damp)
• remove the accessories from the upright section
• withdraw the handle and separate it from the flexible hose (all of these and the following parts have a colored (commonly yellow) release tags/buttons/levers *** Never force anything!! ***
• remove the flexible hose
  
• remove the pipe union to the left of the motor
• carefully lie the machine on its front (wheels uppermost) and remove the u-bend

Check all these parts for blockages/clogging before continuing...

There are now only two areas left that I know of which may cause further blockages. One is the "whole of life filter" located under the dust bin and the other one is inside each of those seven little cones (cyclonic chambers) at the top of the dust bin (root 8 cyclone is usually written on one of them). The following will require some tools and some common sense...

• carefully prise the plastic disc up (the one under where the dust bin rests) use a flat bladed screwdriver or similar releasing it from the lug you can see at the front. Inspect the filter and replace if necessary (when replacing it you may find the original has been glued to the plastic lid - if so gently scrape it off )
• If none of the above has revealed an obvious problem lets turn our attention to these pesky little cones... if you have ever vacuumed up any damp material these can become blocked. You will need a size 15 star drive (sometimes known as torx TX-15) screwdriver. I recommend you buy one with a shaft length of at least 70mm (you will need one this long if you are to access the thermal cut out later)
• Place the bin assembly on a suitable dust sheet.. this can get messy!
• remove the clear plastic outer bin
• undo the three star drive screws at the top and partly withdraw the top ***careful*** you can not fully withdraw this piece. All we are doing here is creating a bit of limited access and "peer room" (before withdrawing the lid you may wish to peer underneath and for future reference note how the release rod is engaged).
  
• now here you have to use a big dollop of care and common sense. By peering into these cones (shine a powerful torch through the sidewall of the cone) see if you can tell if any of them are blocked.
  
• using a small piece of wire or similar gently poke any blockages away. Be careful not to damage the loose but still attached lid.
• reassembly is a bit tricky because you have to re-engage the release rod at the bottom whilst at the same time pushing the lid back into position. Take care not to damage or trap the large rubber sealing ring as you press the lid home Finally replace the three screws being careful not to over tighten.

If none of this revealed anything very positive... Its time to open up and inspect the motor casing/thermal cut out.

**** WARNING**** The next section requires someone who is technically minded, has fiddly fingers patience and a basic understanding of typical plastic goods assembly techniques. As I am not including photo's the descriptions given can only be considered as pointers to how to do it (I'm not writing a Haynes manual here! So if you are a cak handed clot with little or no patience and a tendency to resort to ever bigger hammers - take the vacuum cleaner to an independent repair shop - explain the symptoms, tell them what you have done so far and leave it to them!!

• In order to release the roller brush and belt mechanism turn the vacuum cleaner face down undo the three 1/4 turn screws and carefully withdraw the grey plastic cover (ease the belt guard section gently away)
• coax the belt from the motor end then withdraw the belt and roller from its housing
• Now we need to release the mains cable from the switch area to the motor housing - Undo the screw below the yellow switch
• Working from the back prise the plastic housing forwards (this is tricky) leaving the switch in the on position can help but the main lugs stopping the housing from coming forwards are at the top just behind the big yellow switch button. the best way is to insert a fairly small flat bladed screwdriver in past the upper lugs at the back and put a slight outwards force on the housing tou are trying to remove... patience! Repeat for the other side
• Now undo the electrical connections and release the flex from its channel so it is free to be withdrawn when you release the motor housing
• turn the vacuum on to its front and remove the four torx drive motor housing securing screws (two of these are down a fairly deep recess)
• carefully withdraw the complete motor assembly from the shell
• The remaining part of the grey plastic casing can now be removed (a bit fiddly)
• You should now have the complete motor assembly housed in a black plastic case with the grey intake at one end. Inspect this carefully and you will see that the grey intake is held in place with four lugs. gently prise the black plastic over these lugs and the grey intake will come away
• Now you need to do two things in stages - pressing on the shiny metal motor shaft will push the motor out of the black casing but make sure that at the same time you feed the mains flex complete with rubber boot through the hole.
• Voila the motor is now exposed
• Inspect the motor for any signs of overheating or damage - check the brushes are OK (if you don't know what these are and you've got this far, now may be the time to ask a friend with a bit more knowhow to help!)
  
• Unplug the electrical connections and undo the small Phillips screw holding the plastic assembly to the motor casing (this contains a capacitor and firmly pressed against the metal motor casing is the thermal cut out
• If all else seems OK replace the thermal cut out with a new one and reassemble
• No I'm not going to explain how to do that! For the most part just carefully reverse these instructions! - come on you've made it this far!!

NB. NEVER remove or bypass the cut out. this really could be very dangerous!

I hope this is of some help... Regards to all.

SOURCE: Dyson cleaner keeps cutting out, no blockage found, filter clean.

1. Check the on/off button these can also be troublesome and if you've stood on the cable once or twice you could have a break in the wire and it's shorting, check by turning on and wiggle cable around where it enters machine.
2. Faulty thermocouple, it is held in a white plastic housing screwed with one T15 torx screw to the motor housing. You could replace it but I just shorted mine with some wire and it hasn't failed since and more importantly not caught fire yet!

SOURCE: hi how do you dismantle the head turbine for the

There are two (or is it three) plastic screws on the underside of it. This allows it to be partially split so you can clean the area around the brush roll.
To strip it further needs a Torx T15 bit, but I don't advise doing that unless you know what you are doing and are confident about the re-assembly.
Cleaning around the brush roll area is all most people need to do with these and that is a simple matter.