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Nope.  I built a handful of thermocouples, a digital lab thermometer,
and a PID controller to try to master the dance of temperatures. :-)
I'm totally convinced that a reliable, predictable, steadfast
temperature is required for awesome espresso.  (See www.lucidcafe.com)
Imagine my horror when I found that my Saeco Classico cycles the
boiler temperature between 217F to 275F, a swing of SIXTY degrees!
That's the whole spectrum from sour to charcoal water.  This is the
external top surface temperature of the stainless steel boiler,
measured as the thermostat switches the heater off and on.  Hopefully
the PID controller smoothes the whole thing out.  I can't believe they
use bimetal thermostats to control something as important as
temperature!
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Whatever you do, don't get any Saeco with "Rapid Steam".  I would
gladly trade my Classico for a Rio Vapore without Rapid Steam.  The
Rapid Steam feature requires that the boiler keep water *above* the
boiling point and under pressure.  Then it mixes this superheated
water with cold water to reach ~95C for brewing.  That it works at all
is amazing.  It's a real PITA to tune.  (However, it may have the
advantage of giving more hot water before cooling down.) Other than
that, I'm very impressed with the Saeco.  It uses the same pump (brass
ULKA) as the hallowed 'Silvia'.
When I get the whole PID project finished, I'll put together a web
page with pictures and such.  I'm curious to see what kind of
extraction temp stability I can get with this boiler design.
Best of luck!
-Steve
homeroast mailing listhttp://lists.sweetmarias.com/mailman/listinfo/homeroast

-=> On Thu, 24 May 2001 22:22:02 -0400, EuropaChris said:
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Yow!  That's exactly what I rigged up.. just a PID controller,
thermocouple, and SSR to control the heater.
I got it working this weekend, and the PID is almost magical.. it just
homes right in on whatever temperature I set.
Unfortunately, even this can not save my espresso.  I fear the
boiler/exchanger is simply too small.  There is no way I can get a
full 25 seconds of temperate water.  It either has to start off
charcoal hot, or end sour cool.
From studying your Silvia photos, it appears the Silvia has a larger
'boiler' (and much nicer plumbing).  I have no idea what the capacity
of the Saeco boiler is, but it would be interesting to see them side
by side.
Thanks for the pointer!  Research is ongoing, and I'm up at 2:30AM
from all the "testing". :-)
-Steve
homeroast mailing listhttp://lists.sweetmarias.com/mailman/listinfo/homeroast

Hi, Steve.  From what I've seen of Saeco boilers, they are indeed quite small.  I've played around with a Maestro, and while it has the same pump as the Silvia, the teeny boiler can't do more than 2oz. without loosing it.  However, for the espresso I like, 2 oz. is fine, and it's a great little machine.  It even steams darn well for the size of it.
The Silvia has a 12 oz. boiler, which really makes the difference.  It will pull a 2.5oz. double and hardly even flinch.  No, it's not a pro machine, and it won't stay stable to .3 deg. F like Schomer's PID controlled Marzocco, but I can pull shots with the best.
Have fun!
Chris
homeroast wrote:
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