Hey fellas! Just wondering if any of you out there happen to use a nuova simonelli aurelia 2 group head machine and when ever I flush a group head it trickles water for a good while so I find myself waiting to use it again for longer than I need to be. Is this normal for this machine or should I be looking for a technician to come check this out?
The Aurelia's preinfusion system (SIS) uses a small chamber in the group to ramp the pressure up. This chamber will hold just a bit of water and drip for a couple of seconds after you flush. Without timing it, up to 5 seconds of drips seems right.
This chamber is found under a small square plate (1 inch x 1 inch or so?) on top of the group. After several years of use, the o-ring that seals that chamber can sometimes fall apart and start to leak. I suspect that when this happens the chamber may also fill up more than usual and then drip a little longer. If you are seeing dripping for longer than a 5 seconds or so then this may be what is happening.
If you suspect your chamber o-ring is leaking, take the top panel off of the machine and find that plate. Its really easy to see - if you lock in a blind portafilter and run the group for 5-10 seconds any leak should make itself obvious. If it is leaking, call a tech. (PS, when you do call, make sure to let them know that this particular part is leaking. Most techs should stock this, but if they don't do much with Nuova Simonelli they may not.) Note that if this o-ring is leaking, chances are pretty good that the machine is ready for some other tune-up work too - steamwand pivots, steam valve o-rings, sightglass o-rings, etc.
Simonelli also sells a plug that you can have put in to disable this feature. If you find this dripping extremely annoying, you can ask a tech to do this... but you will lose the pre-infusion feature.
Something you might try for now is to start your flush right when you remove the portafilter. If you use one of the programmed buttons, it will stop the flush while you're still grinding your shot and the dripping should subside before you're ready to lock in.
Hope that helps.
thanks for the info! That's exactly what i've been doing so far; flushing it before grinding. Substituting one habit for another I guess. Your info is gonna be very helpful and as soon as I get a chance I'm gonna check the machine out, thanks!
Here's a pic from CoffeeGeek that shows the plate I'm talking about.
you can pick up the o-ring for that top plate for about 65 cents online and it's really easy to change yourself as long as your not gonna void some kind of a warrenty. if you bought the machine used then go ahead and change all of them and the other pieces like bradly said.