Puck blowout when removing portafilter on La Pavoni

#1: Post by **robkinghorn** » July 11th, 2013, 12:12 am

I searched for this topic but could not find anything on it.

When I slowly remove the portafilter after pulling a shot on my 1975 La Pavoni there is a lot of pressure release going on. It seems to be worse since I replaced all the rings and seals. I know I put the rings on the piston properly. I'm confused why this would change after replacing the seals. Unless I remove the portafilter ultra slowly the top of the puck really blows out. I do the little wiggle technique to release the pressure.

I would appreciate any thoughts about this.

Also, I am in Minneapolis and would like to meet with other like minded La Pavoni users if you are out there.

Thanks!

Rob

#2: Post by **drgary** » July 11th, 2013, 1:15 am

Gesundheit! I think you're talking about a "portafilter sneeze." Search that term on this site and you'll see it mentioned fairly often. It doesn't indicate anything wrong with your machine. It happens when you try and disengage the portafilter when there's still pressure in the brew chamber. To release that pressure you can wait a bit for more coffee to release or raise the lever enough to draw the pressure out but not so much as to introduce more water. At that point you can remove it carefully.

#3: Post by **michaelbenis** » July 11th, 2013, 3:28 am

Gary has pretty much summed it up. In other words, it sounds as if your servicing was sound. However, it shouldn't be more than a minute or so before you can release the PF without a "sneeze". If this isn't the case, it is possible that you are grinding too fine. Backing of a little may not only eliminate the sneeze but also bring you a more finely-nuanced shot. Worth a try...

Cheers

Mike

#4: Post by HB » July 11th, 2013, 6:44 am

From A huge bang when removing portafilter:

HB wrote:The "portafilter sneeze" happens to everyone who owns an espresso machine without a pressure release valve (frequently called a 3-way valve). Those with lever machines can shorten the wait between shots by slowly recocking the lever about half way to introduce air into the chamber and thereby release the water pressure. IMPORTANT: Stop short of the refill port in the chamber.

I've also neglected to tighten the portafilter enough and had the portafilter blow off mid-shot. Talk about a loud bang and a terrible mess!

Or simply wait 1-2 minutes for the pressure to bleed through the puck. By the way, while I was looking this up, I ran across an old-but-good loosely related discussion Lever multiple pull techniques.

July 11th, 2013, 11:16 am

Thank you very much for the great info. Yes, I couldn't think of the term.

You've given me enough information so I can now spend another several hours reading links! That's a good thing.