Post By rustla
EM6910 - Backflush going nowhere
I've got a Sunbeam EM6910 which I've had for a few years.
A few months ago I noticed it was leaking at the group a little during extraction, so promptly replaced the group seal.
At first I thought it fixed the issue, but it just moved the leak from the front of the group to the back where I couldn't see it.
I've noticed my shots over the last few days are pouring very fast, the finer I ground, the worse it seemed to get.
So decided to run a chemical backflush (which I usually do every fortnight - month). The pressure gauge didn't move, water went nowhere (some came out the group while water was being pumped) when I cut the water and the portafilter locked in, like it was pressurised.
I've tried this a few times tonight and given up as I wasn't getting anywhere.
Does anyone have any ideas what might be going on? I thought it might be the collar, but I'm really not sure.
Do you run the cleaning program for it or just do backflushes? Also, when I do my backflush the pumping sounds normal for maybe 20 seconds or so then the noise changes, at which point I hit the button and I get the flush sound out through the 3-way.
And I do a normal backflush every day or two - the fortnight/monthly chemical clean is meant to be the programmed one that takes 10 minutes or so to run.
Try getting some clean/descale liquid from a coffee bean supplier and run it through for a while - not backflushing, just run through maybe half a litre or so. Do the steam wand and the water nozzle as well. The water one won't take much usually but my steam one will run for more than 5 minutes and I still get the sound that seems like it is clearing its throat, so I give it maybe 10 minutes of steam.
Then do it all again with clean water.
I used to have that problem when I had my Sunbeam. I think that when I backflushed, I forced coffee ground remnants back into the lines. The gauge wouldn't move and the backflush couldn't flow, so it just came through the group head. Eventually I just took the machine to the authorised service technician. It was an easy fix for him (I think) as he would probably disconnect some tubes and clean them out. I think it's important to rinse the group head thoroughly using a brush before backflushing as the Sunbeam doesn't have a true three-way valve.
Thanks for the quick responses.
I'll look into cleaning liquid and getting the machine looked at.
Anyone know of a good repair guy in Perth?
If you ring the Sunbeam help line (the number is on the flap to the water tank) they will give you a nearby repairer. Good luck.
If you are a tinkerer, you could open it up and remove and unblock the pipes. On a machine I got going, the symptoms were the same. The blockage was a short (a few cm) copper pipe with a few bends. The blockage was so stubborn, it took numerous soakings, boilings, ultrasonic cleans, pokes with guitar strings (the blockage was between the tight bends) and compressed air. It finally cleared and backflush and gauge worked as intended.
Got the machine back after being serviced on Friday, shots are looking much healthier and the gauge works again.
Not able to achieve much microfoam at the moment, the bubbles are way too big, but I'll keep going, maybe my technique is rusty or having the machine serviced has changed the steam delivery.
Not sure if I'm able to name the service place I took it to, but if you search the web, the place is located in Hilton, in case anyone else sees this thread.
Thanks everyone for your suggestions
just out of curiosity, what did the place charge you for a service?
im having a very similar problem and not getting anywhere with back flushing. tried tinkering a little bit but couldnt gather enough courage to tinker far enough to get to the problem =p
It ended up being $117 in the end
Basically $77 plus parts, they did a full service on it for that too
You've got to add a takeaway coffee each day on top of that though too ;-)
For future reference, there's a Guide for Collar Replacement at http://coffeesnobs.com.au/brewing-eq...how-guide.html - the early links are dead but there's a Dropbox one at the bottom that works. If that dies, PM me your email address and I can send a copy.
The reason I mention it is because to replace the collar you need to open up the machine, so that part of it all is valid for whatever you may want to do inside there.
Why don't you upload the information in the relevant section for an easy reference for all:
Documentation - Midrange