Tearing apart my Miele S5210 vacuum cleaner

December 29th, 2009

This is my vacuum cleaner.

mieles5210 Miele S5210.

It’s a Miele S5210. It’s a very, very good vacuum cleaner. Well, it was until the point that it broke! Actually I was somewhat responsible for that. For a little while now I have been restoring a car (OK, almost 6 years but I am nearly done – www.asciimaton.co.nz/pics). After weeks of filling and sanding of filler I finally sent it off to the panel beaters to be painted. This left me with a garage full of sanding dust. I swept up what I could the used the vacuum to clean up the rest. Unfortunately your average house vacuum isn’t really designed to handle lots of very, very fine filler dust. I ended up clogging it up and the motor stopped running smoothly and instead started stuttering. I needed to take the vacuum cleaner apart to clean it and remove all the dust so it would run properly again. What follows is the procedure I used to take the vacuum cleaner apart. I imagine the process is probably similar to other Miele vacuum cleaner models.

I was inspired to do this page after I found the following page online for a different Miele model (a Miele s300): http://www.sannerud.com/house/miele.html

You don’t need many tools to take the vacuum cleaner apart. Just a Torx T20 driver and a small flat screwdriver to push on the plastic clips that holds the parts together. All the screws used to hold it together are the same. The Torx bit shown here is actually a tamper proof Torx bit with a hole in the middle but it works fine on the screws. Click on any of the pictures for a larger view.

torx20 Torx screw and T20 Torx driver bit.

First unplug the vacuum cleaner and remove the bag and all the filters. The small silver honeycomb filter just clips in place. Remove this so you can then remove the lid.

removinglid The clips holding the lid on.

The lid just slides onto the hinges and two small square clips hold it in place as shown above. Depress the small squares and then slide the lid off the hinges.

honeycombfilter Large honeycomb filter.

The large honeycomb filter is also just clipped in place. Carefully push back the two clips shown circled above and the filter should come out.

rearplastic Rear plastic piece.

The plastic piece at the rear between the two buttons is also just held in place by clips. Brute force will remove this. Just yank it upwards and it will pop loose.

speedselector1 Removing the speed selector.

With the rear cover removed you should see two screws holding the speed selector part in place. Remove these.

speedselector2 Clips holding speed selector in place.

With the two screws removed the speed selector can be removed by pushing in the small clips that hold the front of it in place and lifting it off. This piece just contains the knob that controls the speed. The knob has a stalk that sticks down underneath it that fits into a selector switch on the electronics board.

topcover Top cover screws.

The top cover is held in place with four screws shown, two at the front and two down deep holes in front of each button. Undo these then the top cover should lift off.

electronicsboard1 Top cover removed.

electronicsboard2 Electronics board plug.

With the top cover removed you can see the electronics board. It’s pretty simple really and doesn’t have much on it. The board should be free to pull off now. The only thing holding it in place is the connector shown above. Simply unplug this connector and the board will lift off.

motorcover Inner cover.

With the electronics board removed you should be able to see the screws holding the inner cover in place. There are three at the back and one in the centre as shown above. Remove all these screws.

coverclips Clips holding inner cover.

As well as the four screws there is a clip either side of the cover on the sides of the vacuum. You can simply pop these apart by hand then the inner cover should lift off. There is a small rubber hose that goes between the cover and the cord retractor mechanism which you also need to disconnect from the cover (it will probably just fall off anyway).

coverremovedInner cover removed.

With the inner cover removed you can now remove the motor (which has a foam pad over it) and the cord retracting mechanism. The only trick here is to unplug the connector that joins the two together.

motorplug Motor connector.

The motor and cord retractor will simply lift out. I gave everything a good cleaning to get all the dust out. I used my air compressor to blow it all clean. With all the dust removed from the motor I sprayed it’s brushes with electrical contact cleaner. I didn’t go as far as dismantling the motor itself (March 2010 – OK, I did eventually See below!).

brushes Contact cleaner for the brushes.

The brushes are either side of the motor and I simply sprayed cleaner into the hole at back of them.

After letting the contact cleaner dry I put the motor, cord retractor and electronics boards temporarily back in place the tested the vacuum. You need to be VERY careful doing this as nothing is properly attached and there are exposed mains connections that will bit you it you touch them (don’t ask how I know). Also the vacuum motor is extremely loud when not encased in plastic!

Once everything was cleaned and working again reassembling the vacuum cleaner is basically the revers of taking it apart. Make sure you reattach the small rubber hose and also make sure the cord and plug are free and don’t get caught when screwing all the pieces of the case back together.

After my cleaning and spraying the motor with contact cleaner the vacuum is working nicely again. I know now I should really get a nice shop vac for cleaning the garage and leave the Miele for purely domestic duties!

I can really recommend these vacuums. They are good value for money and very powerful. And now, having seen how they look inside, I can say they are very nice quality too.

Update March 2010.

I have had a few people comment that this page was useful so I decided to post the second part of my vacuum cleaning story in case people find this further detail helpful.

My cleaned up vacuum worked well for a little while but then the motor started stuttering again until eventually it stopped running altogether. Another tear down was in order. This time right down to the motor itself. Again the nice design of the Miele made this an easy job to tackle.

First you need to remove the motor from the vacuum as described above. Then carefully tap off the metal shield on the end of the motor exposing the blower fan. Next remove the nut holding the blower fan in place. Now it was a few months ago that I did this but from memory the nut is a reverse threaded one, i.e. turn it clockwise to undo it. This allows you to pull off the aluminium blower and the flat spacer washer.

IMG_7605_1 Nut and blower removed.

Next you can lift out the two carbon motor brushes. These are simply held in with spade connectors so you can just pull them straight out. In the picture below you can see the female spade socket on the face of the stator housing.

IMG_7608_1 One brush already removed. The other still in place.

The brushes are nice and long so should last a very long time.You can see the long male spade connector on the bottom of the brass housing. You can also see how despite my previous cleaning this brush is still covered in sanding dust. If I didn’t mention it above I should say don’t sand filler off a car (http://asciimation.co.nz/pics/page18.html) then use this vacuum to collect the dust!

IMG_7606_1 Nice brush. Boom! Boom!

With the brushes removed (and cleaned up with electrical cleaner) you can remove the stator. There is a metal spring clip that holds it in place. If you press this down the stator should then slide out.

IMG_7610_1 Spring clip holding stator down.

The electronic controller is attached to the stator and will come put with it. You can see the top of a TO220 type device sticking out of the top of the plastic housing. We get to that in a minute. The inside of the stator and housing were both covered in the sanding dust so I cleaned these up as well.

IMG_7611_1 Stator removed. Note the electronics are still attached.

Next you can carefully pull out the rotor. This has bearings on each end and the lower bearing is a press fit into the housing. You need to carefully pull this out. The rotor will come out in one piece. Be careful not to lose the little flat spring washer though.

IMG_7612_1 Rotor removed.

The observant of you will probably have noticed one of the problems with the motor. The commutator on the end of the rotor, that ring of copper strips the brushes rub against, are filthy and scored. To fix this I carefully mounted the rotor in my mini-lathe. You only need to grip it very lightly in the three jaw chuck. I made sure it was running true and turned it on. I then used some fine wet and dry sandpaper folded into a long strip to carefully sand down the commutator.

IMG_7614_1 Rotor mounted in lathe.

I didn’t try to get the commutator perfectly smooth as I didn’t want to sand too much away. It still has a few small scores around it but it doesn’t need to be perfect. The deep scoring is actually where the edges of the brushes are in contact with the commutator so the brush is in contact with smooth copper on most of it’s face.

IMG_7615_1_1 Commutator after sanding.

Next I cleaned up the aluminium blower which was quite clogged with dust. A bit of electrical cleaner and a poke around the fins with a long cable tie did the trick.

IMG_7617_1

After doing all this and cleaning everything to remove all the dust I reassembled the motor. Since I had given it a good clean with electrical cleaner I left the motor on top of my dark coloured garage roof to make sure it was fully dry before trying to run it again. I wanted to make sure all the cleaner had evaporated out of the motor and windings.

Unfortunately after putting it back in the vacuum cleaner and reassembling everything (with a little Loctite around the rotor bearing where it pressed into the housing) the motor was still dead! I had to take it apart again. This time I removed the motor, opened that up and removed the motor electronics. Again thanks to nice design this module just unclips since it is held in place with spade connectors.

IMG_7625_1 Motor electronics.

The electronics on the motor are incredible simple. Basically it’s just a TRIAC and what I think is a thermal cutout device.

IMG_7626_1 TRIAC and thermal cutout thingy?

About now the problem was pretty obvious. This TRIAC was burned out! A close inspection and a little prodding showed that TRIAC was burned out. Two of the legs were not even connected to the body anymore.

IMG_7628_1 Well there’s your problem!

I am not sure why this happened. I am guessing a combination of a badly connecting and arcing commutator and a motor clogged with sanding dust ended up cooking things. The TRIAC itself is a T2550h 600T which is a 25 amp TRIAC. These are available in NZ but not from the easy places like Jaycar or Dick Head Smith (who don’t really do electronics anymore despite their name). You can probably get them from the bigger suppliers like Farnell or RS but they would cost a bomb and you might not be able to buy just one. So I looked on eBay and found someone in the UK sells them for just a couple of quid. I ordered one of them.

This is the data sheet for this particular part: http://www.datasheetcatalog.org/datasheet/stmicroelectronics/6697.pdf

Once that arrived a week or so later it was a simple matter to unsolder the dead part and solder in the new TRIAC. I reassbmbled everything again (after this many time apart you get good at this bit) and finally everything was working again!

All that was actually done several months ago and the vacuum cleaner is still working happily now. I know these things aren’t supposed to be customer serviceable but it is nice to see that they are engineered in a way that means a customer with the right skills can successfully get in there and fix things.

Update September 2015.

OK, another update. My vacuum cleaner died again! But once again I was able to resurrect it after having to refer to my own instructions here to remember how to take it apart.

The issue was that it just stopped. Was running then just died and wouldn’t work again. I opened it up and found this:

IMG_4401_1

That is the Klixon thermal cutout thingy. Interesting, right back in 2011 a visitor called Dave left this comment for me:

Thanks for a first-class tutorial on the Miele S5210. Well done, it saved me a load of time and effort.

My vacuum cleaner suffered the same fault as yours, and I have found out what caused it in my case. Taking apart the motor, I removed the triac PCB assembly. I noticed that one leg of the fuse had fractured, and there was evidence of sparking across the fracture. Prior to the failure, the vacuum motor had suddenly started making more noise, which turns out to have been due to the intermittent connection through the thermal fuse. After a few minutes, the sparking destroyed the triac and the unit died…but the thermal fuse was still OK! (apart from having one leg sheared off). I was able to repair the sheared leg and replaced the triac, and all is now fine and tickety-boo.

So the problem in this case was not poor filtering, but cracking of the thermal fuse, probably caused by the vibration. I wonder if the motor manufacturer ever assessed the thermal fuse for vibration susceptibility….

By the way, the “thingy” is a Klixon thermal fuse, rated at 18A. It’s hard to find any equivalent fuses, because you need the high current rating, and nobody seems to make an 18A rated fuse quite as small as this one.

Here’s a link: http://www.klixon.com/klixon/motor-protector-3mp-self.htm

Those comments are number 25 and 26 in the comments below btw. The exact same thing had obviously happened to mine. I said then I didn’t know how I would fix it, now I do!

The fuse is two metal sides joined together with an insulator between. The legs are just extensions of the cans. The fuse itself seems fine so I just needed to repair the leg. I used a piece of desoldering braid as a new leg. I used a piece saturated in solder and soldered it to the board first then to the side of the fuse.

IMG_4406_1

Make sure the new leg is only connected to one side of the can. The tricky thing about this fuse (or any fuse) is normally it is a conductor and it needs to go open circuit in overload conditions. If you are not careful the new leg could actually be short circuiting the fuse rendering it useless. You vacuum will work but there will be no protection there. Of course the fuse is normally conducting so just measuring it with a multimeter won’t tell you anything. You have to inspect it visually to ensure it’s not shorting.

After putting it all back together the vacuum works fine again. While apart I gave it a good clean and checked the commutator and brushes. The commutator showed no more scoring since last time and a quick rub over with some glass paper left it clean. The brushes still have a lot of life in them.

IMG_4408_1

Interestingly they wear unevenly. You can compare the wear to the last photo taken over 5 years ago now above. These days I have a dedicated shop vac so this one is only used for household duties which definitely helps with it staying running!

Out of all my web sites and blog posts and projects over the years this is the one page that gets the most comments! I am glad it is of use to people (including myself as it turns out).

182 Responses to “Tearing apart my Miele S5210 vacuum cleaner”

  1. STEVEN Says:

    A LITTLE CLEARER NOW…SO THE VACUUM DOES NOT START…THOUGH THE MOTOR HEAD DOES SPIN, SO THERE IS ELECTRICITY…THE FUSE BY THE CORD IS OK…BUT THE VACUUM IS DEAD…IF THE NEW MOTOR DOES NOT START WHEN I INSTALL IT, WHAT WOULD BE MY NEXT STEP?

  2. Edward Louie Says:

    Did you use genuine miele bags when cleaning up the sanding and file debrie? I have used my miele to clean up lots of construction debrie and it seems fine. I did check periodically to make sure the bag didn’t get to the point of bursting full. The 9 ply miele filterbag plus the premotor filter seems to be a better protection to the vacuum motor than any shopvac I know of. Most shopvag fine dust bags are a thin 3 ply at most combined with a “hepa” cylinder style premotor filter and I doubt the shopvac motor is better protected. I have used my miele to clean drywall dust, gutters loaded with asphalt shingles rocks and dust, paint scrapings, sawdust, and it is still running fine. I tape the lid to the bag with masking tape to keep it from lifting up when I rough it around construction jobs. Unlike shop vacs that clog, the miele hose and outlet is larger than the inlet which prevents clogs. When it does clog at the hose handle I disconnect the hose and run the vacuum with the handle end inserted into the vacuum the suction always clears the clog.

  3. Jon Says:

    I have a snapped door hinge – are they easy to replace?

  4. Phil Says:

    Great article, well written and absolutely accurate. You saved me the cost of new Miele vacuum cleaner.
    Well done, Phil

  5. Simon Says:

    I need to do another update. Mine blew up again but I was able to fix it again. I had to use my own instructions to remember how to take it apart!

  6. Simon Says:

    If you can get a replacement it might be possible. I doubt you could find one though.

  7. Simon Says:

    I don’t think I have ever seen genuine Miele bags on sale here (in NZ) so I have always used generic ones. I would like to find some so I can replace the other filters in the vac. You don’t get them with the generics of course. I do now have a proper shop vac which has a huge, car like, air filter in it since it can be used bagless. My Miele is only used for household things now.

  8. Chris Says:

    Thanks so much! Like a lot of people in this thread, you just saved me at least a couple of hundred dollars. The vacuum is running like a dream, thanks to your fantastic instructions.

  9. Grunf Says:

    Thank you for the tutorial!
    I will need it if anyone knows what is problem when motor speed varying, irrespective of the position of the speed control?
    Thank you!

  10. Sailor-Greece Says:

    Great article congrats for helping so many people!
    Miele is a great tool and thank you for make as save some money..
    Same story here cleaned some paint scrapings and wall dust with aftermarket bag (not the original)and Miele went crazy sounding like airplane trying to take off!Followed your guide and sprayed A LOT of WD40 in the motor cleaned everything and now it’s like brand new.Well that spray is pure magic..
    Thanks again !

  11. Raoul Says:

    Many thanks for the detailed description. I had used my S5211 in my workshop and too much sawdust got into the motor and fan enclosure (I was using cheap filters that often came lose from the hose) until the motor eventually clogged up. I was about to throw the entire vac away as the motor unit spare part was more expensive than a brand new Miele until I found this blog showing how to repair the motor itself.

    I had to remove clogged saw dust from the aluminium fan (the cable ties did an excellent job) and had to replace the Triac. Works again and saved me a lot of money.

  12. Bal Sangeezer Says:

    Thank You!

    This is the first time in ages I’ve actually been bowled over by something on the World Wide Web.

    Was looking to fix a stuck Miele adjustable vacuum stick; whilst I was absorbed in reading this, the wife managed to fix the adjustable pole!

    Thank You!

  13. Graham Says:

    just used youe site to fix vacum and discovered the thingimy also had a broken leg, resoldered and good for another 20 years.

  14. Mr B Says:

    I’d just like to mention that for opening a Miele (properly pronounced “Meeler” btw) S8340’s ‘mrg 403-42/2’ motor, I needed to
    hit the metal cap-level to the plastic lid, with a hammer (four blows), then prise it loose with a flat-headed screwdriver, next:(clockwise) unscrew the very tight, unmarked, nut, with a 13mm drive socket, which I bought for as little as £1 from ‘Poundland’ (GB).

    Hardware shops seemingly tended to sell such tools, in only rather expensive sets.

  15. Paul Says:

    I have not sorted out my TT5000 but the instructions and pics are so good that I am sure that I’ll have no problem. And it has encouraged me to find out what a TRIAC is etc etc. All good stuff and going strong after so many years. Enlargeable pics essential Thanks.
    PS are manufacturers obliged to use tampereproof screws.

  16. PaulH Says:

    I have recently stripped down my S5280 and saw that the brushes have worn down to the point they no longer engaged the armature.
    I got some replacement carbon brushes from the following site (£5+ Postage)- http://www.bargainbrushes.com/catalogsearch/result/?q=6.2+X+11.2+X+29

  17. Moh Says:

    Our Miele Compact S2111 broke down after 3 years. I came across your site and feel obliged to leave feedback.

    In the past most of the motor problems I have come across have been carbon brushes related. So went straight to brushes and after opening it was was clear that problem is somewhere else. Brushes were over 1cm long. At that point I got my multimeter out and checked all the wiring and circuit. (yes, I know I should have done this before opening the motor)The Problem was with pull cord. It was chaffed at starting point inside the reel. fitted two 4.8 mm crimp terminal and shortened the cable by 10 cm. Thanks for putting the details. It was a lot of help.

  18. Mark Says:

    Thanks for your detailed instructions. I used it to clean the motor after i used vacuumcleaner for sucking up dust from chimney! Never use your vacuumcleaner for that. The site for purchasing new brushes was also very helpful.
    Mark

  19. Simon Says:

    Thanks for the great article. My Miele S812 suddenly stopped working. I looked in the phone book – NO appliance repairers in my area.

    We have become such a shallow consumer ‘chuck it out and buy a new one’ society. With this mentality we deserve a super strong China with all its consequences!

    I have a ‘cheapo’ toaster I repaired 15 years ago and still in daily use, and of which I am proud.

    Thanks for your great directions which I am sure will help me with my model.

    Simon NSW

  20. JayH Says:

    Thanks for the tips. In San Antonio, we have a problem with cockroaches getting into our vacuums. Once this happens, even with all the filters, the smell can be permanent. I took my motor apart with your suggestions and cleaned everything. There is no odor now, until the next cockroach gets into it!

  21. Boris Says:

    Hi! What an excellent article!

    I’m having a problem with my engine making a rumbling sound and a burning smell. The higher RPM i use the more rumbling and burning smell.

    So I have dissemsembled everything but I’m stuck at the part where you “pull off the aluminium blower and the flat spacer washer.”

    It’s the white top washer that looks connected with 4 screws as you can see on your own picture here: http://www.asciimation.co.nz/gallery2/main.php?g2_view=core.DownloadItem&g2_itemId=464&g2_serialNumber=2

    The weird thing is I have unscrewed the 4 screws however I just cant seem to get the white top washer off 🙁

    Do you have any recommendation for this? I don’t want to break anything.

    I Hope you remember something.
    Kind Regards,

    Boris from the Netherlands.

  22. Steve Says:

    Another one here with a leg on the thermal fuse that had freed itself. Thanks for the How To

  23. PiersC Says:

    6yo vacuum cleaner good as new – thank you from the other side of the world!

  24. Vagelis Says:

    Thanks for the info. I got my dead vacuum to work again without even buying the part as my thermic protection had just been unsoldered from its place. Yoy saved me a lot of trouble and some $$.

  25. Chris Says:

    UK checking in. Thanks so much for posting this info. I have a 9 year old Miele S5980 purchased from John Lewis. I had it serviced by Miele about 5 years ago when it started having problems. Had been fine since, but was showing some age: the vacuum would cut out and some of the plastics needed replacing. The other week I paid Miele £132 to have it serviced, only have my money refunded and the vacuum sent back as it was deemed “uneconomical” to service. Hogwash!

    (Miele did offer me 20% a new vacuum, but I would prefer to get another 11 years out of this one first.)

    A video from http://www.VacuumSpot.com.au on YouTube explained how to clean the hose contacts. I Krazy Glued (+ Gorilla glued for good measure) one of the broken plastics on the handle and then followed your post on disassembling the motor to check the brushes. Yes, still lots of life left, and yes, they do wear unevenly.

    I actually almost gave up on inspecting the motor when I googled and found your page explaining that the motor turbo/blower was threaded in reverse. Came off with ease once I knew that.

    Net cost so far: £0. Had all the tools on hand, including the Torx drivers. Only thing that will need replacing is the tool lid latch, which partially broken but still works.

    Amusingly, when the vacuum was returned from Miele after the first service back in 2011 or so, the HEPA filter light reset but was not working! That is, the button would not reset the light. When I disassembled the vacuum I plugged it in — being very careful of course — and pressed the button on the circuit board to reset the light. I then discovered that the board was not inserted correctly into the plastics, and was not seated in the snap-fit. Should work fine now.

    Again, thank you. I appreciate that it takes effort posting such esoteric repair info, and I am very grateful as it saved me unnecessary expense.

  26. smiffy Says:

    Managed to strip down my TT5000 as per your instructions, no problems. Stripped motor to find that the rear bearing had disintegrated. Miele cannot/will not supply the bearing, anyone any ideas as to finding a replacement bearing. Thanks

  27. smiffy Says:

    Miele wanted £126.00 for a new motor for the TT5000, they would not supply just the bearing. I found a bearing supplier on the internet and bought 3 bearings for £6 75 delivered free. Now the TT5000 is as good as new. Thanks for your help Miele!

  28. Paul Says:

    I was given a 2yr old Miele cleaner that had sucked up water! It was not repairable but I kept the stator, brushes & triac/thermal cut-out module for spares. My TT2000 will be 11yrs old in August, I have always used OEM filters & bags. I feel Miele spares are extortionate but can’t deny the high quality, longevity & performance of the product.
    I completely dismantled the faulty cleaner & when the brushes/stator wear out on mine perhaps I’ll get another 10yrs life! Thanks to all who have contributed.
    Kind regards Paul

  29. Elrajajo Says:

    @Boris – I had the same problem for a while.

    Just to be clear first: you say ‘white washer’ but there is no washer as such. The whole white end of the motor housing comes off once the 4 screws have been removed. But you must *gently* ease it off. It will come but keep moving your prying gadget around and prising it upwards until it pops off.

    There is what looks like a white washer in the middle of of this piece but it is an unremivalable part of the moulding.

  30. Axel Says:

    So… Have anyone experienced pretty massive sparking at high rpm after reassembling the motor?

    My story of the failing vacuum cleaner is pretty much the same, I used it to create underpressure in a plastic sealed room as I’m refurbishing a concrete wall, and it generates huge amounts of dust. I noticed my vacuum started to go very hot, but didn’t really think much about it, and a few seconds it stopped. So I found your article and started to take the vacuum cleaner apart.

    Nothing seemed to be wrong with the electronics, so all I did was that I blew away what I could see of dust inside the motor, then cleaned the commutator with some fine grained sand paper, and also gave the brushes a few swipes. The first time I reassembled the motor and the sparks hit, I took the thing apart again, and noticed that the commutator had gone dark again. That’s why I think the sparks are generated from the bruses—maybe they need to wear down a bit. Any ideas hos I may get rid of the sparking?

  31. Karen Shipp Says:

    Thank you so much for your brilliant guide. Even with your help, it took all my courage to attempt this, but to my amazement it has worked! As an older woman with athritic hands, I found it quite hard to get some of the bits apart, and to get the deep screws out. A visitor had broken the vac, I don’t know how, but afterwards the motor would go for a second or so, then cut out. But if I left it switched on, after a few minutes the motor would have another go, then cut out. I took everything apart except the motor. When I turned the motor blades, it squeaked. I cleaned up everything (lots of fine dust and sawdust) as best I could with no hoover (!), and then sprayed everything with WD40.
    And now it works. I will only buy the proper bags from now on, and won’t use it on the highest settings.Thank you again, you have saved me spending £200 or more. You are a hero!

  32. Gary, belfast Says:

    Great info, much appreciated, thanks

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