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Date: 01 Feb 2007 13:42:32
From: I->Ian
Subject: Thermosyphon Stall Solved
A few months back I requested help on a thermosyphon stall on my
Vibiemme Domobar Super e61 group.

Several kind folks responded with solutions, but alas it turned out to
be the CBLF, not the hardware.

I was not running enough water out of the group when doing a cleaning
flush after pulling a shot. Opening the valve for a couple of seconds
drained the upper chamber of the group. No Water, No Thermosyphon
Flow.

If I don't flush or flush lots, no stall.

Thanks to all who previously responded.

And to Michael and Angelo at http://www.espressoresource.com and
Stefano at http://www.espressocare.com. These guys are tops!




 
Date: 02 Feb 2007 11:12:31
From: Eric Svendson
Subject: Re: Thermosyphon Stall Solved
Hi Ian -

I read the first account of your thermosyphon stall and was pretty impressed
with the excellent diagnosis (that I sure couldn't have come up with) you
received and the efforts you made to uncover the problem. I was thinking
that you accidently bumped the level sensor down when you were installing
the PID's thermocouple. BTW, what did you use to bend that HTTC
thermocouple (which is normally not recommended for field bending) ?

And while I'm at it - what does CBLF mean?

I guess I don't understand unless the valve opening and the pump starting
were not in sync.

Skol,

Eric S.





"I- >Ian" <someone@nowhere.com> wrote in message
news:82n4s2h902ekh539tb6628q69bh110r8de@4ax.com...
>A few months back I requested help on a thermosyphon stall on my
> Vibiemme Domobar Super e61 group.
>
> Several kind folks responded with solutions, but alas it turned out to
> be the CBLF, not the hardware.
>
> I was not running enough water out of the group when doing a cleaning
> flush after pulling a shot. Opening the valve for a couple of seconds
> drained the upper chamber of the group. No Water, No Thermosyphon
> Flow.
>
> If I don't flush or flush lots, no stall.
>
> Thanks to all who previously responded.
>
> And to Michael and Angelo at http://www.espressoresource.com and
> Stefano at http://www.espressocare.com. These guys are tops!




  
Date: 02 Feb 2007 11:31:53
From: I->Ian
Subject: Re: Thermosyphon Stall Solved
On Fri, 2 Feb 2007 11:12:31 -0500, "Eric Svendson" <erics@erols.com >
wrote:

>Hi Ian -
>
>I read the first account of your thermosyphon stall and was pretty impressed
>with the excellent diagnosis (that I sure couldn't have come up with) you
>received and the efforts you made to uncover the problem. I was thinking
>that you accidently bumped the level sensor down when you were installing
>the PID's thermocouple.
>
The TS stall occurred before I installed the PID. In retrospect, all
the solutions weren't.

Accident? Moi? Surely you jest!!! I takes pichers afore I start ;-)

> BTW, what did you use to bend that HTTC
>thermocouple (which is normally not recommended for field bending) ?
>
I bent it over a wooden dowel. Very carefully. The part in the boiler
is also gently curved to position the bead.
So far, so good.

>And while I'm at it - what does CBLF mean?
>
Carbon Based Life Form or IOTH = Imbecile on the Handle

>I guess I don't understand unless the valve opening and the pump starting
>were not in sync.
>
For lack of a better word, I was 'burping' the system. I was running
just enough water to clear the screen and didn't run the pump quite
long enough. The water drained from the upper chamber when the brew
valve opened, leaving an airspace in the upper chamber. If I ran the
pump long enough, the upper chamber refilled and the TS flowed.

What remains a mystery is why running water out of the boiler would [
could? ] cause the TS to restart. Coincidence??

My next machine is going to have tempered glass boiler and tubing so I
can _SEE_ what's going on!

The long and the short is if I never run a cleaning flush, the TS
never stalls. If I run a long cleaning flush the TS never stalls. If I
run a cleaning flush with a blind basket and let the pressure build,
the TS never stalls.

The only time the TS stalls is if I open the brew valve for a short
interval - exact time undetermined. And it's probably variable
depending on the state of the machine at the time.

>Skol,
>
>Eric S.
>

Slainte,
Ian
>
>
>
>
>"I->Ian" <someone@nowhere.com> wrote in message
>news:82n4s2h902ekh539tb6628q69bh110r8de@4ax.com...
>>A few months back I requested help on a thermosyphon stall on my
>> Vibiemme Domobar Super e61 group.
>>
>> Several kind folks responded with solutions, but alas it turned out to
>> be the CBLF, not the hardware.
>>
>> I was not running enough water out of the group when doing a cleaning
>> flush after pulling a shot. Opening the valve for a couple of seconds
>> drained the upper chamber of the group. No Water, No Thermosyphon
>> Flow.
>>
>> If I don't flush or flush lots, no stall.
>>
>> Thanks to all who previously responded.
>>
>> And to Michael and Angelo at http://www.espressoresource.com and
>> Stefano at http://www.espressocare.com. These guys are tops!
>