Bet you haven't seen this before - EM6910
I'll start this thread off with a history of the machine, it isn't mine, it's a friend's. It was provided as a replacement for their other machine when it was damaged in transit after having a steam pump replacement. This in itself was a battle, trying to get a new machine from this company. Some service centre in Melbourne or something.
Anyway, going back about 4 months, they finally got this machine, given to them in "fully tested and in 100% working order". That was the case for about a month, and then it went downhill.
Firstly, the group handle had to be turned further and further tighter so it wouldn't leak. Then, they noticed a puddle of water underneath the machine. Upon inspection inside, water was spraying out of the seal between the 3 way solenoid coil and brass tube. This is when I received the machine.
I disassembled it to replace the o-ring in the valve or tighten it, but it wasn't as simple as that. This is what I found:
You can see the split brass at the base of that nut there, never seen anything like it before, not sure if a lot of use or manufacturing defect was the problem here. I ordered a new solenoid.
As a result of this leak, water had gone all over the board. When the machine was turned on, at the end of the heating up cycle when it's meant to be ready for use, the pump just turned on and kept running. The power light was flashing red at this stage, might have had some other lights flashing, I can't remember. Took the board and control board out and dried as best I could but it still didn't work. Tested most of the passive components and none were faulty, I then replaced the triacs because they were cheap, this also had no effect.
So then I went and bought a new board for it. Installed the new board and new solenoid and finally the machine was back in working order. Then I loaded up the portafilter and pulled a shot with the top off the machine. First thing I saw, water spraying out of the connection between the brass line to the thermoblock and output of the pump. Upon closer inspection, it had been tightened so much that the o-ring had squeezed out of the side of the connection causing the water to leak. It also a had a ton of some sort of sealing lubricant on it, presumably to aid in the sealing or something.
I fitted a new o-ring and fixed that leak. I'm not a fan of brass thread into plastic thread much, it's a stupid idea. Unfortunately I didn't take any photo's of this.
Next I replaced the group head seal which arrived and the group handle was locking in snug now. Friends got their machine back (finally) and all was well.
We come to today, approximately 2.5 months after it was repaired. The machine wasn't turning off with the buttons on the top and was making a weird crackling noise sometimes. Aside from this, everything else was working. It was in this state for about 2 weeks and then the RCD in the house started tripping. Assessment by an electrician was that the coffee machine was the problem. I sent an email to the company who I bought the control board off to see if there was any warranty cover on it, it seemed as though the fault would have been in the board again. There was warranty and a new board was supplied to me in a timely fashion. Not sure if I can mention names here or if it would be considered anti-sponsor promotion but if you've ever had to order parts for appliances from a large online Australian seller, you can probably guess who it is. I would recommend them.
I replaced the board tonight after checking the inside of the machine again. No evidence of any water leaks, no burn marks or physical damage. Powered the machine up, started normally, all was well. Them, I manually ran the pump to check everything was working. As soon as the pump kicked in it made that horrible rattling noise that pumps with no water in them makes. Waited until it pulled some water in but it was taking ages, finally saw water appear but it was only just tricking out of the group. The rattling/crackling noise was still there. I feared a damaged pump at this stage.
Ceased pump operation but the crackling noise was still there. I put my ear a bit closer to the machine to see if I could identify where the noise was coming from at which point it started getting a bit louder. I work in electronic repairs, putting my head near it wasn't a good idea in the first place but I wouldn't have guessed what happened next. As soon as it got louder i reached for the power cord, didn't make it. BOOOOOOOOOOOMMM. Sparks flew from inside the machine and smoke poured out.
Not the first time something's exploded on me so it wasn't that bad but I was certain the machine was extremely damaged and the house breaker had tripped. Surprisingly, the machine was actually still on and ready and the electricity was still on.
Here's the result:
Not gonna lie, I dunno why this happened. The neutral wire to the solenoid has literally exploded out of it. The crackling noise and restricted flow must have been the coil shorting and semi-closing the valve. There was no visible damage or water leaks near the solenoid so I don't know what caused it.
If anyone has any ideas on why this happened or have experienced it before, let me know. Probably not going to bother repairing it any more unless the company I bought the solenoid off will replace it. Unless someone has a spare solenoid they'd be willing to let go cheap?
TL;DR this machine was given to my friend in what is obviously not a fully tested and inspected state and whoever carried out the repairs to it previously need more experience or guidance. It's a wreck.
Judging by the flurry of replies, this mustn't be that interesting. In other 6910 news, I'm pretty over these machines. Seem to be far too much trouble than they're worth.
Have one at work now, steam thermoblock not heating. Luckily I have my machine to test it with, turns out the control board wasn't telling the steam thermoblock to heat. Yet another expensive repair........
I didn't see it - not sure why. I usually check any of the SB threads. Are the PCB's that expensive or is it the time required for diagnosis and fix?
I'm about to pull mine apart to check the steam system - last few days it seems to be struggling to stay strong enough to steam my milk properly. I've got a practice machine I'm going to pull apart first (which unfortunately also has a non-functioning steam pump) just to make sure I know how to not break things before I work on my main machine.
I found a place in Melb does steam pumps for $59 so if I ahve to replace it, that seems reasonable, but I am hoping to find something awry once I get into it.
Yes, the time required is expensive. Being that it's at work I had to charge standard rates.
The customer ended up taking the machine and will fix it himself. Just got me to do all the hard work-.-
You dont happen to have a spare solenoid coil do you?
Distinctly possible - taking apart the spare machine tomorrow (had Uni stuff to get in today) so post a pic so I know what you're talking about or a link so I can see one.
Thanks man, this is a picture i found of it cos i don't have a proper picture. It has a small black or brown box around part of it with 3 wires coming out.
I also took the solenoid coil (the small black or brown box) off it today and found that the brass had split again, causing a massive water leak into the coil which caused it to explode. I can't explain why this happened, the valve was working properly up until this point where it's just failed again. I can't understand it.
I also took the solenoid coil (the small black or brown box) off it today and found that the brass had split again, causing a massive water leak into the coil which caused it to explode. I can't explain why this happened, the valve was working properly up until this point where it's just failed again. I can't understand it.[/QUOTE]
Like Journeyman, fooled by the title (generically bored with "haven't seen before" when usually I have... in spades). I only found this because I was going to ask him how his steaming was getting on.
FWIW, I have seen more "cowboy repaired" 6910's than any other maker added together. Must be an industry somewhere (although five senses did such a botch up of my older 6910 maybe they are official repairers "moonlighting" with even lower quality "workmanship". Shudder.).
My take: 6910's are killed by several snafu's in the manual, bad water (Metro Perth is probably unrivalled for this one) and poor cleaning practices: exaggerated by the manual failing to tell users basics liking how to remove the showerscreen or use the milk wand without slurping up milk... As a machine, they are otherwise reliable & capable of really good coffee.
Anyway, let me know if you need spares, as I have a 6910 with a stuffed mainboard and fully working steam system (Perth WA). Killed by Perth water plus "cleanliness snafu's courtesy of the manual". Be warned, Journeyman has first dibs... even if he insists on using those dreadful internal "taste? You want to taste the coffee? How odd?" cleaners.
All the best
Here's some photo's of the damage to the solenoid this time around. Organised for a replacement solenoid now, i'll be checking the machine to see if there's a reason that it's killed 2 solenoids, can't see what it'd be seeing as the machine works perfectly when it is working at least.