EM6910 Noises in the night

flatwhite2

For the very first time the other night the low water alarm started just as I finished cleaning down the machine and I didn't top up the water as I was mere seconds away from turning it off and enjoying my brew, thinking I'll fill it up in the morning.

During that night, at approximately 2:20am I was awoken by the main pump pumping water through the group for about 2-3 seconds.  I got up and checked it out, the machine was off (ie no lights but I leave it turned on at the wall) and nothing seemed amiss.  After checking a few other things through the house I was just hopping back into bed when it did it again.  Wondering what the hell was going on I grabbed my multimeter (I'm a sparky by the way) and tested the outlet and found 252V...sort of high.  I logged the voltage for the rest of the night in case it did it again but it didn't.

Now I have had the machine for probably 18 months and it has never done this before so I  was thinking it was something to do with the low water so I set up the machine again the next night and set up my meter to log the voltage.  Sure enough at 4:20 am I was woken once again this time the machine only ran once.  A check of the log and at that time the voltage was the highest it had been all night at 255.34V.  I have been trying to get information out of energex as to when the hot water switching frequencies were operating that night with no success.

So at this stage I'm thinking that there is some flaw in the circuit design whereby when the following conditions are met the group pump will operate
- The machine is turned on at the socket-outlet
- The machine is turned off at the control panel (not on standby with the light flashing)
- The water tank is low so that the alarm would sound if it were turned on
- The input voltage is above 255V
- Switching frequencies are being transmitted by the energy authority to turn on/off the hot water.

Now I think its a combination of high voltage and switching frequencies because the voltage goes up and down all night and when withing 0.3-0.5 of a volt of the max it didnt operate and switching frequencies are sent several times through the night so I believe it is when the two come together that there is an issue.

I left the unit with a full tank of water and nothing happened last night.  As I dont have enough equipment to log two things at once I will be trying to log for switching frequencies tonight and see if the unit operates and will let you know how I go

What I am hoping is that other members with this machine can
A) Set up their machine to be turned off with a low water alarm and see what happens
Advise if they have had similar instances which were unexplainable that they can relate to this story.

askthecoffeeguy

could it be a ghost in the machine? pat

allanjohn

My 6910 has jsut been replaced after a recurrrance of this problem where the machine would switch itself on. The tech told me there was an internal leak from the pump, which shorted the main board. I must say that customer service was great - they have attended promptly to all my issues. But this machine is just not up to 10 cups a day - depsite all the references in the manual and brochures to "professional". I will try to take the new unit back to Myer as I have no confidence in the Sunbeam machine for our needs. It may be great for 2 or 3 coffees a day. And yes, it seems the 11-month point is where the problems start - that's when it firs started showing the signs and went in for its first repair.

askthecoffeeguy

Really, I've had a play on these machines and thought that they did a pretty far job of knocking out the coffee - my only concern with thermoblocks is that the thermo's tend to cark it sooner or later - but I had no problems pulling some beautiful shots - still, if you can afford the money spend a bit more and you will get a better machine (I still think the em6910 is a 'category killer' though - and the next bracket tends to kick in at at least $1000 more expensive!)