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I have a 6 year old EW1006 (an Aqualux with a mechanical timer) which has increasingly developed a mind of its own.
During the first year or so it sometimes seemed to go through the full cycle, but with much less drum action than normal. I didn’t think much of it.
In the last year or so though it started occassionally stopping mid cycle (mainly on wash cycles)… It needed a power-off, rotate dial, and power on again before it’d restart.
But then it sometimes seemed to go through a full programme cycle, but with no drum action at all! That could be either during wash cycles or spin cycles….
More recently, it sometimes it goes through a cycle at high speed(!) – e.g. during a rinse sequence it will fill, then immediately drain again, then immediately fill again, etc (with no drum action or even with the controller giving any time for drum action)?!
Finally, it has started doing some bizarre things with the drum – e.g. during wash cycles suddenly speeding up the drum (before shutting down when the shaking got too bad!), or at the end of spin cycles, when slowing down, suddenly changing spin direction (with a horrible screech/shake as it doesn’t wait for the drum to stop first!!)
At the moment the machine sort of behaves OK if it’s very cold, but after it’s been on for 10 mins or so, all of the above are possible, with the most common being no drum action, stalling mid cycle, or going through a sequence at high speed….
In summary, it basically seems possessed. Any ideas what the root cause(s) might be? Should I take it to the dump, call a repairman, or call an exorcist?!!
(I’d like to repair it if possible. It’s basically a good machine and all the bits seem able to work and otherwise seem to be in reasonable condition. I am also VERY loathed to add yet further to UK landfill….)
Help!
Mark
p.s. I live in a hard water area and never used any descaling products if that’s relevant……
Re: Electrolux seems possessed!!!
Mark,
No it is not possesed but rather in need of attention to the motor thats all. Probably needs a new set of brushes and the Tacho checking out :tup:
Also the manifold needs close attention etc etc. Not a costly exercise at all but one that requires expert attention nonetheless. Not a DIY job!!!
We may have someone on this site local to you that can sort it? Try this link:-
Repairs@Martin
Re: Electrolux seems possessed!!!
If it’s what I think it is, the motor tacho generator coming loose then it’s a straight forward enough repair Mark.
These are pretty good machines on the whole and well worth a look at, try the repairs@ module and the directories for an engineer, if they don’t throw someone up in your area, pop your postcode back here and I’ll check another list I have.
Dave.
Re: Electrolux seems possessed!!!
Thanks Martin/Dave – you guys are stars!
Phew! So it *probably* doesn’t need a new timer/controller then?! That would be excellent news!
I assume that the brushes might account for the motor not starting when warm?
But what exactly is the tacho? I assume it’s some sort of motor controller/regulator? Is this an electronic or mechanical speed controller, and is this mounted on the motor or nearby? (FWIW, I can see a smallish module nearby, which appears to have all the motor wiring running to it. It’s about the size of a notebook PC power brick, but looks like a tuppaware box. Is that it?)
I assume that it is somehow interacting with the main timer/controller, which might account for the main timer just clicking through the rinse cycle sometimes without pausing for any motor action? Am I on the right lines?
When you say coming loose, do you mean you suspect the connectors to this module (assuming it is that remotely mounted electronic assembly), or something else – i.e. like it needs replacing?
Also, why do you suspect the manifold, and what actually is that?(!)
I checked the repairmen database and it doesn’t show anything. I’m in Cambridge (CB4).
FWIW, I’m an electrical engineer, but more electronics than electrical, and know a lot more about PCs than I do about washing machines. I might tackle this repair myself if it’s largely a case of cleaning and reseating a connector and swappind some brushes, but if thre’s anything more than that would otherwise prefer to call the ghostbusters!
What do you reckon – DIY or repairman, and, if so, any names?
Thx
Re: Electrolux seems possessed!!!
The motor tacho generates a signal which can be read by the digiboard or tupperware box and so allows motor speed to be controlled. The magnetic armature has a habit of working loose over time and can cause the coil assembly round it to be pushed off. Eccentric things then start to happen….. Check on the end of the motor, with the power off.
If no joy, engineer time.
Regards,
Penguin45.Re: Electrolux seems possessed!!!
I’ve just had a good look under my machine.
From your description I think I’ve found the tacho. If I’m right then it’s on the very end of the motor shaft (at the opposite end to the the belt drive) on a section of motor which is around 4cm in diameter, and has two thin wires coming from it. I can only see a half sugar cube size lump on the outside, and I can’t tell off-hand if there’s any more to it inside. There is however a shaft end cap right next to it which also looks pretty much in place and is quite rigidly mounted. The bit of the motor structure that it’s mounted to also seems aligned and quite rigid. What actually is the tacho? Is it some kind of magnetic sensor? If so, should I remove the end cap and check if there’s a magnet inside that’s working loose from the drive shaft?
Whilst I was fiddling I also had a look at the brushes, and they seem to be in reasonable shape – i.e. plenty of carbon left, and making good contact with a reasonably clean comm. The machine has only had light use and there’s no obvious sign of lots of carbon from wear.
At this stage it looks to these inexperienced eyes that the tacho is perhaps OK? Is that right, and should I therefore be thinking that the motor control electronics might be faulty, or haven’t I actually yet checked the tacho properly?
I can see how a tacho fault may account for the drum speeding up, and *possibly* even account for the non-starting (tho I’d have suspected the brushes for that), but I don’t understand why it explains the spin suddenly changing direction, or the main timer rapidly clicking through the fill/drain sequences in the rinse cycle?
If the motor control electronics are also partly responsible for timing the motor action then I guess I’d be more suspicious that it’s this module which is causing the problems. I note that penguin called the electronics here a “digiboard”, which says to me that this is perhaps a lot more than just a few high voltage switches; i.e. it probably has quite a complicated motor controller built in? In which case it presumably does some of the motor sequence timing too? Or am I just completely barking up the wrong tree? 😆
Thx
Re: Electrolux seems possessed!!!
If so, should I remove the end cap and check if there’s a magnet inside that’s working loose from the drive shaft?
Yep, that’s the area to check 😉
Dave.
Re: Electrolux seems possessed!!!
The timer is just a box full of switches. The machine is controlled by the digital control board – dedicated processor etc. The timer only moves if the digiboard tells it to. SO…… When you set the programme, the switch combination in the timer tells the digiboard which programme to run and away we go. Now, unlike the “old fashioned” electro mechanical machines which advanced every three minutes, this one advances when the predetermined sequence has been completed for each stage. This particular machine will, for instance, shut down functions that do not conform to the programme. This could be motor speed control. If the motor is switched on and a signal is not detected after a preprogrammed period of time, that’s a fault and the programmes shuts off the motor.
The down side of this is that the digital contol board can (and does) go wrong. So can the timer unit, although this is less common. The mention of the timer unit clicking through several positions quickly would point at the digiboard, although (I’m afraid to say) there is no guarantee of this. I have attended these machines where consistant use with a faulty timer has caused the digiboard to pack in as well.
Engineer time?
Regards,
Penguin45.Re: Electrolux seems possessed!!!
Thanks again guys.
Sadly I’m away from home at the moment but keen to look into this further when I get back. You’ve given me some really good insight into how this all works, and how the functionality is distributed. Perversely, whilst I probably sound like a complete numpty to you with my lack of washine machine knowledge/experience, I could probably actually do a component level fault level diagnosis on the digiboard if I had to (I’ve actually designed quite a few state machines in my time!) What you’ve told me fills in many of the gaps in my knowledge and gives me a sporting chance of getting stuck into this now. I’m really, really grateful for that insight.
Next stop that tacho, and then the digiboard…… I will let you know how I get on!
Re: Electrolux seems possessed!!!
It’s not the tacho……
I stripped the tacho down last night and it was fine. It’s quite nicely made, and whilst there’s clearly room for improvement in how it’s made, the most obvious problem that would occur doesn’t seem to have.
I don’t know if this is how they are on all washing machines, but I assume this is how it works on my Electrolux.
On the end of the motor shaft is a small lump of plastic. Embedded into it are a number of magnets (6 I think?) The magnets are aligned radially – i.e. like spokes on a wheel – and I assume are oriented NS, then SN, then NS, etc. This produces a set of six magnetic fields looping out from end of each magnet and back into each neighbour.
I assume the tacho sensor is just a coil wound radially around the whole lot? Alone, this wouldn’t sense anything, as the field is radial and the coil is axial, so, as the motor shaft turns there are no net changes to the field cutting the coil. The clever bit is that the coil is surrounded by two stamped pieces of steel, one mounted on either side. On the inside of the coil are shaped fingers. These fingers are the same size as the ends of each magnet. There are effectively two sets of fingers, one on each stamped steel component, and they fit together alternately on the inside of the coil. I haven’t counted them, but I assume there may be twice as many fingers as there are magnets?
As the rotor turns there are alternatively N and S poles under each set of fingers. The fingers couple the field back through the tacho sensor, so that a field of alternating N/S crosses the coil. In effect, the steel assemblies are a radial to axial field converter, and pulse doubler. Each revolution of the motor therefore produces several AC cycles of tacho output – perhaps 12 cycles per revolution?
I assume the problems which can arise with this design include the disks coming apart (which would weaken the sensor output), or the disks slipping so that the two sets of fingers converge (which would also weaken the output, nd make the signal lopsided). Alternatively a magnet could work loose from the plastic mount?
On my tacho, everything seems present and aligned, so I’ll wager it’s producing good output. As I’ve said before, I suspect the digiboard is playing up, so when I get another chance that’s the next thing to check.
If anyone’s still interested I will let you know how I get on…..
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