Backflushing the VII

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Niko

Backflushing the VII

Post by Niko »

I know this was posted before the forums went down back in December so I wanted to re-spark this conversation. I remember some people mentioned weak backflushing with the VII.
I wanted to start by saying that I actually got hit by water while backflushing mine the other day, it has that much pressure! Some were complaining that the unit wasn't building up enough pressure, maybe it was caused by using the rubber disk in the double-basket instead of the single.
blacroix

Post by blacroix »

Are you supposed to use the single?

My pressure is set at 8.2 bars - might turn it up just slightly to around 8.5. Backflushing seems a bit weak - I don't get much of anything going on until I shut off the pump - but that's the 3-way valve releasing, right?

Also, after your post about the regulator being based on relative pressure compared to water line pressure, I think I'm giong to check my expansion valve setting - is that also relative to the line pressure? I'm assuming it is not, based on where it is in line with everything else... assuming it is more relative to elevation and atmospheric pressure. Correct me if I am wrong on this.
Niko

Post by Niko »

Yeah, you're supposed to use the single basket with the rubber disc.
I use a true blind basket for mine and the backflush pressure builds up even higher - reason why I got hit with water.

Mine is also at 8.2 bars but I think the weak backflushing is maybe caused by the lack of a good seal (the rubber disc) in the basket. I'd leave the 8.2 bars alone if your incoming line pressure is at 25 psi.
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chas
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Post by chas »

My S1 came with a small rubber disk that only fits into the single basket. However, my VII came with a larger rubber disk that requires using the double basket.
Chas
LM GS/3 & LaSpaziale Dream v 1.25 (US 120V)
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pierre

Post by pierre »

hmm, I never used any baskets when backflushing. My rubber backflush disk has a little nipple in the center which fits into the exit hole in the portafilter. At least, that's how I assumed it was supposed to go... works fine for me.
RGoldman

Post by RGoldman »

Does loading too fine of a grind and tamping too hard so that NOTHING, not a drop, comes out of the filter count as backflushing? :oops:
Ok... so it only happened once and it was really early in the morning.....

How often is backflusing (the correct way) necessary? How often with the cleaning solution?

Ron
blacroix

Post by blacroix »

According to the instructions:

- Backflush weekly
- Backflush monthly with cleaning solution

It says to NOT use cleaning solution more than that - I'm assuming it's tough on the rubber seals or something. Anyone have a more informed reason?
Niko

Post by Niko »

Too much cleanser over-lubricates the parts, causing them to squeek on E61 machines. On the Spaz you're looking at similar problems, such as very leaky valves from over cleaning with detergent.
RGoldman

Post by RGoldman »

I'll make sure not to over do it then!
Do you drop out the screens and clean them every week too?
Niko

Post by Niko »

Yeah, the screens get a Cafiza bath every week. You can keep a good shot count by counting the spent pucks in your knockbox, when it fills - it's time for a cleaning...
blacroix

Post by blacroix »

Niko wrote:Yeah, the screens get a Cafiza bath every week. You can keep a good shot count by counting the spent pucks in your knockbox, when it fills - it's time for a cleaning...
Wow... I fill my knock box every day. Two doubles in the morn... 1-2 after work... wife has one in the morn, one after work. :) Counting is way too much work for me... I just clean on Sundays when I have some down time...
Niko

Post by Niko »

That'll work just fine.
I've pulled over 2400 shots on my other S1 in just a little over 6 months. You do the math, it's a LOT OF COFFEE. This is why I keep 125 lbs of greens in the dining room.

I have to backflush everyday and with Cafiza every week, at least...
RGoldman

Post by RGoldman »

125lbs of greens! And I thought I had a big stash put away at the moment!
What's your favorite SO or blend that you roast for espresso Niko?
blacroix

Post by blacroix »

HOLY SMOKES! How long does it take to go through that?!

...and does your doctor know? :) Maybe we could get a special setup so you could just get an espresso dripping directly into an IV...
Niko

Post by Niko »

I've cut down my espresso intake to 4 shots a day, imagine how much it was before that. I can still put away 3 shots in a row 10pm in the evening and still sleep by 11:30pm (the same evening). I guess I'm a freak.
I constantly order more greens to try out and I roast every other night, one of my favorites is Australia Mountain Top for strraight espresso, it's sweet, smooth and creamy which goes down so easily. I like it so much that I only serve it to my wife and myself (almost done with 20lbs in just a couple of months). We go through a lot of coffee, friends and relatives are always dropping by for their fixes. I've had many occasions when 50+ shots were pulled in a session, the Spaz gets a real workout - the plumbing gets cleared out, knockbox fills 3 times over and the shower screens get changed at the end of the night. Sometimes it feels like a cafe in my kitchen.
Some of my favorite blends would have to be a nice central (a C.O.E. winner) with some top notch African beans. Another good S.O. for espresso that I like is the Rwanda Bourbon, it makes a very nice cup when mixed with the Panama Boquet. It's got some zing to it. I think I have about 17 or 18 varieties at the moment. It goes fast in my household, hence the two Vivaldi's (I & II) and the Quick Mill Anita.

My current avatar shows the Aussie being pulled into 2 Pavinas, this is the only coffee so far that tastes this good straight out of the roaster. It was still warm when it hit the grinder burrs.

Gentlemen, start your grinders...
RGoldman

Post by RGoldman »

Hard for me to tell yet if we are using less coffee now than we were before we got the new machine. We both love strong coffee so I was always cramming as much into the swiss gold/TV or Fp that would fit.
I find that I am drinking 3 to 4 double shots a day now and I don't think it's any more than I was going through before.
My first espresso roast is good although, the only thing I have to compare it to is the Vivace Dolce and Vita. The blend is Brazil YB, Guat Huehue, Rwanda, Java, and 10% India robusta PB. Lots of crema and pretty smooth tasting.
I am trying to decide on what to roast next.
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