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Topic: Vacuum coffeemaker: First stall (5 msgs / 159 lines)
1) From: MichaelB
I've been making vacuum coffee for over a year, first the Yama 5 cup, then
the 8 cup, and now the Cona C since Xmas. Never even a hint of trouble or an
indication that something could go wrong. I typically get a forceful rise,
enough to really jiggle the glass filter, and the water shoots up very
quickly. Then I stir to wet all the grinds, wait a minute, and turn off the
flame. The coffee descends rapidly, and you can watch the grinds with bloom
on top get sucked dry and see the foam appear in the bottom bowl. Result,
velvety smooth coffee with just the tiniest hint of residue in the bottom of
the bowl after pouring the last drop into an insulated carafe.
This morning the coffee went up as usual but would not come down. Instead of
streaming down in force, it barely dribbled down. When it was evident it was
not coming down on its own I used kitchen tongs to grab the glass filter and
managed to turn it enough to get the coffee to flow down. It was reallly
hard to budge so there was still a very strong pressure differential. There
was no loss of vacuum - if anything it was the opposite. Could it have been
too strong?
The only thing I recall that might have been different is that I had it on a
real high flame (higher than usual) till almost ready to rise and then
turned it down considerably (lower than usual) just before the water started
to rise. Could this have been the cause?
The coffee, two day old Green Stripe, is so good that the slight sour taste
of sitting on the grinds too long is a minor component of the overall
wonderful taste. Quite drinkable and enjoyable. Just finishing my last cup
Maybe this will never happen again (hard to type with fingers crossed :-)
but any thoughts on how to avoid a repeat will be appreciated.

2) From: Barry Luterman
This is a multi-part message in MIME format.
It sounds as if you are using a Cory Rod. My guess is you are right. You =
were boiling too vigorously and popped the rod as the last water =
traveled north. When the rod popped some grinds got between the rod and =
bowl resulting in a stall.

3) From: gene nandrea
I brew with a Yama so I do not have experience with the Cory. I am thinking
that if grounds were stuck in the filter it seems like it would allow more
grounds to pass south and not cause a stall. From the description of the
problem it sounds like the vacuum was intact but something was clogging the
filter. Are there changes in the grind that might cause more fines to be
produced which might in turn clog the filter? I don't know if it would help,
but I do not add the ground coffee until all the water is north, then stir
and start the timer.
On 2/22/07, Barry Luterman  wrote:

4) From: Aaron
Since you still had vaccuum, can't say the seal gave way.  I have 
noticed that some coffee's, I dont want to say are more 'dusty' because 
I really can't prove that.. but they just seem to be more 'clogsome' 
than others.
I use a Bodum electric vac pot and also use a swiss gold 1 cupper 
extensively and yes there have been issues there too.  Some coffees just 
dont like to play well during the drain phase....  for some reason my 
Kona's typically tend to be a big PITA for the first cup I brew but 
after the filter is heated up by one dose, rinsed well and made ready 
with another, the clogging problem tends to all but go away.  I have 
also noticed that some of the SG's tend to be more picky than others.. 
and cleaning makes a HUGE difference.   Rinsing in water is not enough, 
you have to soak them in cleaners to really clean the screen properly.  
I actually use an ultrasonic cleaner, and even after a soak in coffee 
brite or any cleaner of your choice,  throw it in the US for 3 minutes 
and you'd be amazed at the crap you still pull out.  Might want to check 
how clean your bottom filter is.  Wetting it down before grounds adding 
might help too... run it under warm / hot water, throw grounds in, put 
rig together like youd normally do for coffee.
Only other thing i can recommend without knowing all the details  is,  
grind it a bit coarser see if that helps, and on that, get a spoon and 
drag it across the bottom filter of your vac pot just enough to clear 
some of the grounds / grunge away and it should be enough to let the 
force of the vacc suck it down into the pot.  If you do have vaccuum 
present it will suck the liquid down if you clear a path for it.   Given 
the grounds have been steeping already, it shouldn't hurt the flavor too 
terribly much.
Are you sure the thing was being held down by a strong vaccuum and not 
just squinched down really tightly?
Let us know if you figure out what's gone wrong here.

5) From: MichaelB
Thanks for the ideas. I'll try again tomorrow and will grind coarser.
IMO coarser grinds often produce sweeter brews than the finer grinds so
there shouldn't be a downside to opening up the grinder a bit.
BTW, the Cona vac pot comes with a glass filter.http://www.sweetmarias.com/prod.brewers.vacuum.shtml.No need to shop for an
aftermarket Cory or other antique glass rod. I love the Yama pots with the
cloth filters but I love the all glass Cona even more. I'm still amazed at
how well they work. (Well, perhaps just a little bit less amazed than I was
On 2/22/07, Aaron  wrote:

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