hhmm. thanks yeeza i hadnt thought about that one.
im assuming you mean the 3-way solenoid?
any idea what me is to be doing to check this out?
if you have a multimeter, check to see if there is a short to the earth (green/yellow) contact. There should be no continuity there. If so, thatll answer your question. Maybe see if theres some moisture between them too that may be affecting it. Its hard to tell without seeing it obviously. All done without it plugged in obviously.
I cant imagine it having anything to do with adjusting the OPV though.
Oh and the usual electrical disclaimers apply.
Maybe JavaB could lend a hand here.
From an electrical perspective, a backflush represents a condition where the pump is running at a maximum, but youd only run it for a second or so.
Realistically, there would be more "load" on your electrical system just pulling an espresso, since the pump is also pretty much running fullpower and in this case for 30 seconds.
If a normal shot is not tripping your electrical system, a back flush shouldnt either unless something else is amiss.
What exactly is tripping, an RCD or a Circuitbreaker? [note, these are diffferent]?
Essentially, the solonoid will behave the same way for a shot or a backflush, so I dont think this will be the cause.
At what point during the backflush does the power trip [ie whilst the brew switch is on or when it is released]
Are there other things on the circuit [eg kettle or toaster] that may be running at the same time?
Id be more inclined to suspect there is some water leakage that only occurs under the pressure induced by a backflush but not for a shot, so the OPV may be worthy of further investigation.
If you also have an RCD, this may make sense.
Unplug the machine and check inside for any signs of moisture, especially around the OPV, boiler, pump and threeway valve.
I guess if the OPV was incorrectly adjusted, such that a pressure >9bar was obtained, something may be getting too stressed during the backflush process.
Did someone call ::)Originally Posted by YeeZa link=1214223242/0#3 date=1214275007
Id say it is moisture in or around the three way valve or the pump causing leakage to earth...... when the three way and pump are under pressure there might be a small water leak..... and that is causing a partial short to ground and tripping the earth leakage breaker.....
Its not the sort of thing which can readily be found by use of a multimeter (they dont supply enough volatge to cause the unit under test to "break down") but a megger (high voltage insulation tester) will probably be needed.
About all a "home user" could do would be to unplug the wires to the solenoid (with power off of course ::)) restore power and then see if the breaker is tripped..... if not the problem is with the 3 way..... if it still trips the problem is with the pump. No water will flow from the group with the three way disconnected by the way.
Other than to check visibly for signs of water leakage at the offending part (3 way or pump)..... and make sure there are no leaking fittings.... the next step would be to replace the offending item..... or take it to a repairer who does have the right gear to check for insulation break down.... and they can replace the faulty "bit"....
thanks VVV much for your suggestions. *:-*es and hugs
yeeza *- thanks for sending out SOS signals to JavaB
and i dont have a multimeter
reubster - whats a rcd and whats a circuit breaker?
the safety switch is being tripped.
and thats what confused me too - the load for a shot is about the same as the load for the backflush. i turn the pump off as soon as i hear the pump quieten down.
javaB - ill have a look around inside for signs of h20. and then try your suggestion of unplugging the wires to the 3-way.
so when i do this (remove wires to the 3 way), should i try a backflush and see what happens?
you mention that no water exits the group *so where does it all go?
if it IS a leak which is only showing under pressure, then simply fixing the leak should fix the problem then right?
you guys rock
A RCB = ELB = earth leakage breaker which is often called a safety switch as well.... it will have a small "test" button on it which, when pressed, causes the breaker to drop (the test switch causes a small leakage current to earth). A circuit breaker just has a large "switch" which drops when the current overloads it (or you switch it off).... no test button!
When you remove the 3 way plug, test the unit as you did when it failed before. The OPV will allow the water to flow either back to the tank or into the drip tray (depends on the machines design).....
If pressure is causing water to leak and wet the connections..... then if you can find it - and fix it - then the problem should go away (once the water has dried up of course).....
Is the circuit tripped while the pump is going during the backflush or when you turn the pump off and the 3-way valve opens up?
If the former then Id be looking for a leak someplace.
If the latter then it sounds like the water coming out of the discharge pipe from the 3-way valve is splashing onto an area that is causing the trip.
From your description it sounds like its the latter. Check and make sure your discharge pipe is located properly so that its output is going into your drip tray and not splashing elsewhere.
Java "Arent electronics fun?!" phile
not as much fun as electronics AND water *:oOriginally Posted by Javaphile link=1214223242/0#8 date=1214282159
thanks again SO MUCH guys. ill have to open her up and see when the house is tripping - during brew or after.
yes its an elb with a test switch!
i have to say its been kinda annoying having to re-set the 4 clocks around the house... *:(
aaron "off to play with water and many volts"
and in the meantime, can you explain how water dripping trips the elb?
im assuming the water is dripping onto some wiring?
The water/moisture creates a short circuit between an active line and earth. The whole body is earthed too, and most other things metallic. Its a safety thing. The water dripping itself doesnt cause the trip, just what it touches, ie, the wiring.
ok so i opened her up tonight and found some signs of water leakage around the place so tightened things up. pulled a shot no probs.
chemical backflushed with fingers crossed.
pulled the pump faster than i usually would after hearing the pump quieten. ALL GOOD!
then waited 15 secs and went again.....and BUGGER. maybe 2 secs AFTER stopping the pump, the rcd kicked in and down went the house lights. a little cursing ensued followed by me sitting here frustrated.
so, im thinking maybe ill get someone to have a look inside.
1: any suggestions for someone in melb?
2: now that i have baclkfush chemicals sitting in the system, is that going to be a problem? (ie do i need to get the machine to backflush real quick to avoid chemicals sitting for too long?)
thanks again guys.
In my experience with prosumer stuff, this is more often than not caused by a faulty element. Your machine is a tad more complex though....
Faema and cimbali are imported by two of the biggie Melbourne coffee roasters. You could try either or even the Veneziano techies could most likely assist.
so after chris suggestion. i have got "craig the techie" at veneziano to have a look tomorrow (very kindly). hopefully his LM mojo translates to Faema mojo
Update: “Craig the Techie” from Veneziano had a look at my machine today for me. Massive shout out to him as he is a true magician and a great bloke to boot.
Even prior to this whole backflushing issue, the shots I was pulling since resurrecting my machine were so bad it wasn’t funny (not even a little bit). I couldn’t drink straight espresso out of her - all my shots needed milk to tame the utter ugliness of it all. I presumed it was a brew pressure issue, and perhaps a temperature issue (they’re related, right?).
So I dropped off my machine, left him a note as to the backflushing issue and the fact that I had played with the OPV but didn’t have a clue what the brew pressure was.
Picked up my machine today, took her home, left her on for an hour, and once I had dialled in my grinder (after having relied on stovetop espresso for a few days),
I PULLED THE BEST SHOTS I HAVE EVER PULLED AT HOME. I am talking syrupy, dark, tiger striped, heavy bodied, luscious, sweet goodness.
HAPPY CAMPER? YOU BETCHA.
So Craig, YOU ARE AN ABSOLUTE LEGEND AMONG LEGENDS
Ps: for those of you who want to know WHY the safety switch was “turning out the lights”…it was…………..drumroll please……a dodgy solenoid coil.
Goodnight and G-d bless you all
lucky guess ;)Originally Posted by roknee link=1214223242/0#16 date=1214996209
Good to hear all is back up and running - and even better than before!
yeah i was going to give you ten points and the chance to move into the bonus round...but then thought i might offend reubster javaB or javaphile..as they were on the money as well.
so ill have to call the referees on this one and THEY can let you know the outcome while i slowly slowly back away.... ;)
oh it is SO good to make decent espresso.
pics to come....