Many thanks for all your replies.
OP stated that this is the 2nd Bosch machine that has caused the same problem. A few basic checks of household electrics might be a worthwhile investment, starting with a ramp test of the RCD in question?
I bought the previous Bosch two years ago. It was a smaller 7kg machine. My current one is an 8kg Bosch Series 6. Within three weeks the 7kg machine started intermittently tripping the RCD. The trips were more frequent than the ones I'm experiencing now with this machine. I got the Bosch engineer (the same guy who recently looked at my current machine) to look at it. He ran the electrical, quick wash and spin tests on the machine and checked the sockets. He didn't look inside the machine. He said he couldn't find a fault on the machine (the previous 7kg one) and attributed the problem to the dedicated mains socket that I have for the machine - despite his socket testing gadget showing no faults.
He advised me to put the machine on another socket. I did this and the machine was still tripping. So I was forced to call out another Bosch engineer. He ran the same electrical, quick wash, and spin tests on the machine. It intermittently tripped in front of him while running the quick wash cycle. So he declared a motor fault. This second Bosch engineer also did not look inside the machine.
The brand new 7kg machine was declared faulty so I paid a bit extra and got it replaced with my current 8kg Bosch from John Lewis. My current machine has gone for almost two and half years without tripping. During this time it was connected to the dedicated mains socket that the first Bosch engineer said was "faulty". If my RCD or the power socket was faulty, then surely my current machine would not be able to go for almost two and a half years without tripping the mains. This is why I found it hard to accept the recent diagnosis from the Bosch engineer (who also diagnosed the previous machine).
Is this machine plugged into the same circuit as everything else in the kitchen ('kitchen ring')?
What else is plugged into this circuit? If you could list everything and anything plugged in it would help.
My uneducated gut is thinking cumulative earth leakage tripping the RCD so that next step for me would be to unplug everything and start plugging things back in and monitoring the earth leakage.
I would combine that with a load check on a clamp meter while the machine e does a cycle, just to get an idea of how much leakage there is. It may just be you've got too much leakage and the RCD does its job.
You may find having a separate radial (on am RCBO) for your white goods eliminates the tripping issue
Hi thanks
This morning I decided to find out which circuits my devices and appliances are on. My RCD is only labelled with A,B,C,D and numbers. So it was difficult to figure which circuit breaker is responsible for what.
The big thing I've learned today is that all the appliances in the kitchen (microwave, boiler, kettle, washing machine, and fridge, and a small lamp) are all on one circuit breaker. BUT this is not the circuit breaker that trips. All this time I presumed the circuit breaker that trips was responsible for the machine and all the appliances in the kitchen, but it's not the one that trips.
The circuit breaker that trips covers the following:
Wireless router, 19" flat panel TV, small speakers and subwoofer (all three are connected via a four plug extension and are always on/standby)
BT cordless phone main base unit (plugged directly into a mains socket and always on)
Smartphone charger (always plugged in, but turned off at the mains)
Small decorative lamp with five lights, but only one bulb installed (always plugged and switched on at the mains, but never in operation while the machine is running)
Small DAB radio (always plugged in, but turned off at the mains socket)
A small low power single bulb lamp and BT cordless phone charge station (connected via a four plug extension. Always on at the mains. Phone charge station is always on, lamp rarely used never in operation when the washing machine is on)
That's everything that's plugged into the circuit that trips.
Break it down into the main categories and decide which to pursue next: 1. The WM is faulty and sometimes causes excess earth leakage due to water ingress, chafed cables, faulty components. This might correlate with a cycle position, load weight, temperature etc. A maintenance person might find evidence during testing regardless of whether a trip occurs, but intermittents can be notoriously difficult to find. Although I don't like the sound of the Bosch guy's attitude I would not blame him straight off for not finding the problem, as I have spent literally years looking for similar faults. 2. The WM is not faulty but the total leakage on the circuit is high. At a particular point in the cycle or under certain wash conditions its contribution to the total leakage increases and the total passes the RCD trip threshold. It can be complicated to discover the necessary pattern of activities that provokes a trip by experiment due to the number of parameters, e.g. how long since the grill was used and whether the fridge compressor starts during the WM's spin. But, electrical testing could give a reasonable indication as to whether the total leakage is high enough for it to be relevant and worthy of consideration. Note that the amount of leakage is not directly related to the power consumption of each appliance or whether it is switched on. A switched-off PC can leak as much as 100 switched-on heaters. 3. There is an actual fault on the wiring that is being physically disturbed by the WM, e.g. a damaged cable under a floorboard that the machine stands on, that only vibrates when spinning. Pulling the WM out could conceal this problem indefinitely. Visual inspection of the wiring is the only way to rule it out.
Hi, thanks
I've never had an argument with a service professional before until I encountered the Bosch engineer who recently looked at my machine. I just wanted him to inspect the machine properly and asked him to take the top panel off and check for stray wires, chaffing, see if the drum is catching, etc.
And that's when he flipped. He said he didn't need to take the top panel off as he could see everything through the hole in the back. I asked him several times, and he became sarcastic and invited me to look at the machine since I was the "expert". I declined and I said I wasn't going to pay if he wasn't going to inspect it properly.
At that point he said he didn't need to be in my home. I tried to reason with him and said I would be happy to pay if he would just look at it properly. His body language became increasingly hostile and he repeatedly kept saying "you've refused to pay" and used that as an excuse to storm out.
He shoved the machine back under the worktop and left it unbalanced and unplugged.
He also lied in the engineer's report. He said he wanted to carry out a 15-minute quick wash cycle on another socket. I would have been happy for him to do this, except he actually told me he wanted to run a cycle for over an hour on another socket while he went away. I declined because I wanted him to visually inspect the inside of the machine properly first, something which he said wasn't necessary.
I also noticed there were no readings for any of the electrical tests on his report.
I wrote a long email to Bosch, but they are standing by him and his conduct.
Based on the symptoms I described I was expecting a more thorough inspection of the machine beyond the basic tests. I just didn't expect such poor service from Bosch.
I really hoped to rule out a fault with the machine. I've just discovered today that the actual circuit breaker that trips isn't the one covering the circuit that the washing machine or any of the kitchen appliances are on.
All this time I presumed that the circuit breaker that was tripping was the one that the machine is on (my RCD has no labels identifying which breaker belongs to which room), but it isn't.
I don't know whether this means that the machine is not faulty. Perhaps you are right. The earth leakage is so high from other devices on the tripped circuit and the machine's "normal" earth leakage is just tipping it over.
But from what I've worked out today, the machine is not on the circuit that is tripping. Could the earth leakage from a device or appliance on one circuit cause the circuit breaker on another circuit to trip?
Thoughts appreciated.