Why is my AEG washing machine tripping my fuse box?

[Palhil]

Hi.

I have been having a problem with my AEG 7000 Series Washer Dryer (L7WEG851R) tripping my main fuse box over the last week. I am trying to diagnose what the issue may be. Here is what has happened so far. The machine is three years old, so it is now out of warranty.

Last week I ran my regular program of Cotton at 30°C for 1 hour 9 minutes. The fuse box then tripped around 15 to 20 minutes after starting.

After the fuse box was reset, the machine continued the program for a couple of minutes but it tripped again. I tried a couple more times to reset the trip switch and each time it would work between about 20 seconds to 2 minutes before the trip would go off again.

I decided to try the Rinse program instead. This again tripped the fuse box within a couple of minutes.

As a last resort, and to try and get the clothes out of the machine without being soaking wet, I tried the Drain & Spin program. This finished with no problems.

By this point, I had done a little online reading and suspected that the heating element might be causing the problem. It would make sense since the machine wasn't tripping immediately when I switched it back on and had not tripped during the Drain & Spin program which presumably doesn't use the heater at all. From what I could see it looked quite easy to replace. I took the gamble to buy a new heater rather than pay for an engineer call out.

I bought a genuine AEG heater element and fitted it without a problem. With the machine now empty, I tested my original Cotton program. It worked without any issues for half an hour, so I considered it a success and stopped it.

The next day I ran the Cotton program with a load of washing and again it tripped 14 minutes in with 55 minutes still on the clock. I removed the washing, rinsed it by hand, put it back in the machine, and ran the Drain & Spin program with no issues.

The next day I decided to test the machine again with no load. It ran through the full 1 hour 9 minute program with no problem.

Thinking the cause of the problem may be the weight of the washing somehow shifting the drum and touching a wire, I opened up the back and top of the machine to see if I could identify any wires touching something that they should not. I pushed in any small plugs to make sure they were seated fully. I could also not smell any electrical burns that you sometimes get from overheating.

I ran the Cotton program again but decided to try a smaller load of washing with the drum less than a quarter full. However, yet again, it tripped the fuse box at the 14-minute mark.

I ran the Drain & Spin cycle with no problem. After taking the washing out I decided to test it again on the Cotton program. It completed the whole 1 hour and 9 minute program without issue. I had accidentally left one sock inside. So, at the moment it seems I can successfully wash one small item of clothing at a time.

I can not work out what the issue may be. It seems to be something to do with either the weight or volume of clothes plus, possibly, a specific event in the cycle. I noticed that there is a cable that goes to the back of the drum. I'm not sure if that is a sensor for the temperature or the amount of water. Could it be something to do with this? My only other thought is that because it seems to trip at 14 minutes, that it may be one of the valve releases for the water that goes to the separate compartments in the soap tray.

Any ideas? Obviously, I'm not an electrician or engineer but I would like to identify the likely issue to save time if I have to call out someone to fix it.

Any help appreciated. Thanks.

Paul

 

[brianmoooore]

I assume it's a RCD that's tripping, not a MCB.
Heating element and a water leak, dripping into the electrics are the two main causes of what you describe, but you seem to have covered both of these.
If the fault only occurs when the machine is loaded, then your theory of the drum touching a wire that it has worn through the insulation is plausible.
Note that if the RCD that trips is shared with other circuits, then the problem may well be a N - E fault on a different circuit, and nothing to do with the washing machine at all. If the washing machine takes a pulse of high current, such as when a motor starts, or the heating element switches on, the current in the neutral wire can flow back to the fusebox, then part of it can flow back the neutral wire of another circuit, though the N-E fault, then back to the fusebox through the earth wire, bypassing the RCD, throwing it out of balance, and causing it to trip.

 

[Palhil]

I assume it's a RCD that's tripping, not a MCB.
Heating element and a water leak, dripping into the electrics are the two main causes of what you describe, but you seem to have covered both of these.
If the fault only occurs when the machine is loaded, then your theory of the drum touching a wire that it has worn through the insulation is plausible.
Note that if the RCD that trips is shared with other circuits, then the problem may well be a N - E fault on a different circuit, and nothing to do with the washing machine at all. If the washing machine takes a pulse of high current, such as when a motor starts, or the heating element switches on, the current in the neutral wire can flow back to the fusebox, then part of it can flow back the neutral wire of another circuit, though the N-E fault, then back to the fusebox through the earth wire, bypassing the RCD, throwing it out of balance, and causing it to trip.

Thanks for the reply. Yes, it is the RCD that is tripping. It sounds like it would be best for me to get an electrician to take a look at it rather than just a washing machine repairer.

 

[brianmoooore]

Are all the sockets in your property supplied by the same RCD?

 

[Palhil]

Are all the sockets in your property supplied by the same RCD?

I believe so. I'm not at home at the moment so I can't check. It's a one-bedroom flat. I'll double-check this evening.

 

[brianmoooore]

If there is a socket controlled by another RCD (does your cooker panel have a socket on it and is on a different RCD?) try plugging your washing machine into it, and see what happens. Use a good quality extension lead if necessary, making sure it's fully unwound.

 

[Palhil]

If there is a socket controlled by another RCD (does your cooker panel have a socket on it and is on a different RCD?) try plugging your washing machine into it, and see what happens. Use a good quality extension lead if necessary, making sure it's fully unwound.

There is only one RCD covering everything. The cooker has its own fuse in the fuse box and is directly wired into a switch in the kitchen with a microwave in the connected socket. I could plug the washing machine into there but I don't know if that helps. I have had this washing machine for three years with no issues and no major changes to power usage elsewhere in the flat. I think in any circumstances I'm going to need to get someone in to check the electrics of the washing machine and the fuse box while they are at it.

 

[brianmoooore]

Nothing will be gained by moving to another socket if you only have one RCD covering everything, so, I think you've reached the end of what you can check yourself.
Your single RCD covering everything is far from ideal, and isn't permitted under the current regulations, although these aren't retrospective. The current set up is dangerous and inconvenient in that you could be plunged into complete darkness at any time at night, and be unable to switch the power back on.

 

[Palhil]

Nothing will be gained by moving to another socket if you only have one RCD covering everything, so, I think you've reached the end of what you can check yourself.
Your single RCD covering everything is far from ideal, and isn't permitted under the current regulations, although these aren't retrospective. The current set up is dangerous and inconvenient in that you could be plunged into complete darkness at any time at night, and be unable to switch the power back on.

Thanks for the help. I'll get an electrician to look at it all and work out how to best update the fuse box.

 

[Palhil]

Hi. Just thought I'd give a final update in case anyone else comes across this thread with the same issue.

Before I contacted an electrician I tried one last thing. As I mentioned, the washing machine only seemed to trip the electrics when it had a load in it but not if it was empty. Initially, I thought that it might be the weight shifting the drum or putting extra stress on the motor. However, I had also noticed that there was a wire going into the back of the drum about a third of the way up from the bottom. I assumed that this might be a sensor of some kind and that the higher water level was affecting it. I had nothing to lose so I unplugged it and started another wash cycle whilst keeping an eye on it. This time it worked without any problem. So I decided to take the risk and buy a replacement for this component. It turns out that it was the humidity sensor. The replacement cost £30. When I received it I swapped out the old one. I couldn't see anything wrong with the old one. It's literally just two small wires attached to a plug on one end and a sealed plastic probe on the other.




I was still slightly worried that the fault may lie further down the connection and that by disconnecting the sensor I had just stopped the current from reaching it. However, I have now completed a few full washes with the new sensor and have had no issues.

So there we go. I have no idea how or why that sensor caused such a major issue.

Even though I also bought a new heating element that proved redundant, in the long run, I think I saved money by not having to call out someone to repair it. It was an interesting challenge to work out if nothing else.

?

 

[brianmoooore]

I would guess that the old probe isn't quite as sealed as it looks, and that water has entered it, causing an electrical leak from its wires to the drum.
Well done for sussing it out.

 

[LukeD]

Its great to work things out !

 

[Jan pol]

Hi. Just thought I'd give a final update in case anyone else comes across this thread with the same issue.

Before I contacted an electrician I tried one last thing. As I mentioned, the washing machine only seemed to trip the electrics when it had a load in it but not if it was empty. Initially, I thought that it might be the weight shifting the drum or putting extra stress on the motor. However, I had also noticed that there was a wire going into the back of the drum about a third of the way up from the bottom. I assumed that this might be a sensor of some kind and that the higher water level was affecting it. I had nothing to lose so I unplugged it and started another wash cycle whilst keeping an eye on it. This time it worked without any problem. So I decided to take the risk and buy a replacement for this component. It turns out that it was the humidity sensor. The replacement cost £30. When I received it I swapped out the old one. I couldn't see anything wrong with the old one. It's literally just two small wires attached to a plug on one end and a sealed plastic probe on the other.

View attachment 85575


I was still slightly worried that the fault may lie further down the connection and that by disconnecting the sensor I had just stopped the current from reaching it. However, I have now completed a few full washes with the new sensor and have had no issues.

So there we go. I have no idea how or why that sensor caused such a major issue.

Even though I also bought a new heating element that proved redundant, in the long run, I think I saved money by not having to call out someone to repair it. It was an interesting challenge to work out if nothing else.

?

Hi. Just thought I'd give a final update in case anyone else comes across this thread with the same issue.

Before I contacted an electrician I tried one last thing. As I mentioned, the washing machine only seemed to trip the electrics when it had a load in it but not if it was empty. Initially, I thought that it might be the weight shifting the drum or putting extra stress on the motor. However, I had also noticed that there was a wire going into the back of the drum about a third of the way up from the bottom. I assumed that this might be a sensor of some kind and that the higher water level was affecting it. I had nothing to lose so I unplugged it and started another wash cycle whilst keeping an eye on it. This time it worked without any problem. So I decided to take the risk and buy a replacement for this component. It turns out that it was the humidity sensor. The replacement cost £30. When I received it I swapped out the old one. I couldn't see anything wrong with the old one. It's literally just two small wires attached to a plug on one end and a sealed plastic probe on the other.

View attachment 85575


I was still slightly worried that the fault may lie further down the connection and that by disconnecting the sensor I had just stopped the current from reaching it. However, I have now completed a few full washes with the new sensor and have had no issues.

So there we go. I have no idea how or why that sensor caused such a major issue.

Even though I also bought a new heating element that proved redundant, in the long run, I think I saved money by not having to call out someone to repair it. It was an interesting challenge to work out if nothing else.

?

Hi I've had the same problem with my AEG washer dryer. Before it started tripping a few weeks before it wouldn't complete the drying cycle. I've got the new humidity sensor but how do you remove the old one from the grommet? I am a bit cautious to give a hard pull but is that the way to do it? I'd appreciate your advice.
Jan ( enthusiastic amateur)

 

[Jan pol]

Hi I've had the same problem with my AEG washer dryer. Before it started tripping a few weeks before it wouldn't complete the drying cycle. I've got the new humidity sensor but how do you remove the old one from the grommet? I am a bit cautious to give a hard pull but is that the way to do it? I'd appreciate your advice.
Jan ( enthusiastic amateur)

I managed to remove the sensor by gently levering it out. The tip was covered in a film of white debris well stuck down . Not surprised that it didn't work! New probe in - works fine now. Jan

 

[DPG]

I managed to remove the sensor by gently levering it out. The tip was covered in a film of white debris well stuck down . Not surprised that it didn't work! New probe in - works fine now. Jan

Great stuff !