Is my 3-way valve working correctly?

[MDL]

I may be crazy, but I think that my 3-way valve may be sticking.

I've had my VII since April and my recollection is that initially at the end of a shot there would be a clear release of pressure and the sound of water shooting into the drip tray (like backflushing, but less violent).

Now, at the end of a shot there is a sound and the pressure releases but I don't hear a release of water into the drip tray. Rather, when I release the portafilter there is a gentle run of water into the drip tray.

Am I crazy, or has something really changed and what is "correct"?

Thanks,
Mark

[Niko]

Do you backflush with detergent often?
That valve will stick if backflushing isn't part of your routine maintenance, I speak from experience because I've been there...
One time I had a really bad leak that would fill the drip every two hours because the valve was stuck partially open from all the coffee oils. Another time the valve was making a horrible squeaking sound when it engaged because it was jammed up, once again from lack of detergent backflushing.
This one took quite a while to fix and get rid of the noise, it was a matter of 3 weeks before it went away completely with really hard backflushes using Cafiza.

[MDL]

I routinely backflush with Cafiza every month (I only make 1 or 2 doubles per day). In addition, I backflush with water more frequently.

[Richard]

. . . initially at the end of a shot there would be a clear release of pressure and the sound of water shooting into the drip tray (like backflushing, but less violent).

Now, at the end of a shot there is a sound and the pressure releases but I don't hear a release of water into the drip tray. Rather, when I release the portafilter there is a gentle run of water into the drip tray.

There are several factors that can affect what you describe, including dosage and grind, which you don't mention.

I know that dosage in the range of 12-13 grams, ground finely enough to be pulling 1.0-1.5 oz in about 20-25 seconds, allows a significant water column on top of the puck, leaves a very soupy puck, and there is not a strong whoosh of water from the three-way valve. On the same machine, larger doses result in a firm, dry puck and that wet whooshy exhaust of water from the three-way.

[Niko]

I routinely backflush with Cafiza every month (I only make 1 or 2 doubles per day). In addition, I backflush with water more frequently.

Try it every 2 weeks for the next 3 times, it can't hurt the machine and it might remedy the situation.

Has it been a month since the last backflush? If so, this might be the culprit. Have you been using beans that are more oily lately? Your usage is pretty low but oily beans do tend to gunk things up quicker between cleanings.

I know that dosage in the range of 12-13 grams, ground finely enough to be pulling 1.0-1.5 oz in about 20-25 seconds, allows a significant water column on top of the puck, leaves a very soupy puck, and there is not a strong whoosh of water from the three-way valve. On the same machine, larger doses result in a firm, dry puck and that wet whooshy exhaust of water from the three-way.

Richard, I've never tried down dosing that far. I've been meaning to try it and with certain S.O. beans that make me want to shoot the Vivaldi, I'll have to keep that it mind.

[MDL]

I use a level single basket worth of beans (Peet's Espresso Forte) tamped to 30 pounds with an Espro tamper to pull close to 2 ounces in about 25-30 seconds. In general lthe puck is pretty solid but moist. There is not a layer of water on top of the puck after the pull. I have never weighed the beans (don't have a scale) and I've always been unsure of when people start to time their pulls. My major concern has been taste and getting close to 2 ounces without blonding or soupy pucks.

[Niko]

I guess that answers my question about oily beans...
Mark, you may want to try some good hard Cafiza backflushes. Peet's tend to be on the oily'er side of things. I'm not saying it's bad, no harm done just more cleaning is involved. Some of the beans I put through my equipment tends to be just as oily. It sounds like an accumulation of oils have finally worked their way into sticking the valve a little. Try the detergent now and then backflush with regular water every 3 days after the cleaning.

[chas]

There's no dictate that says the 3-way has to make a lot of noise when it opens. If you don't have water on top of your puck, that's a good sign that it's working.

I have noticed during backflushing if I fill the pf with water first, there is very little noise when the 3-way opens. However, if I don't fill it with water first, water is explosively expelled from the 3-way so the air pressure in there has a lot to do with how forceful the water gets expelled.

[MDL]

Thanks everyone.

I have done a hearty Cafiza backflush and will repear every few weeks instead of every month.

Perhaps my low usage actually requires more frequent backflushing than I had thought; although I don't have high volume, I do use oily beans and they could generate oils that get stuck because they sit there in the machine?

Anyway, when I backflush I certainly get violent release of water into the drip tray, so I think that the valve is working.

Take care,
Mark