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Date: 20 Mar 2007 21:53:50
From: Robert Harmon
Subject: tuning a pstat
I've a Nuova Simonelli Personal a friend gave me. It looks to be in pretty
good shape & when I bench tested it everything worked - sort of.

Besides the usual suspects; leaks & crud build up, the first thing I noticed
was that if I aimed for 1.1 - 1.3 boiler pressure the water in the Styrofoam
cup never exceeds 184F. If I want it to reach 195F I have to set the
pressure at 1.6 bar. I understand that these gauges are stone-age technology
but could it be that far off? Also, at 1.6 bar the temp is 196F for the
flush, 193 & 191 for the next two 1.5 ounce pulls, then drops off quickly
for subsequent pulls.

I would've thought that, given the boiler size, incoming cold water wouldn't
drop the HX temps that fast. If HX's are that unstable where are the
advantages over a single boiler if you still can't pull shots consecutively?
Is it considered to be enough of an advantage being able to steam & brew at
the same time?
--
Robert (Hmmmmmm!) Harmon
http://tinyurl.com/pou2y
http://tinyurl.com/psfob
http://tinyurl.com/fkd6r






 
Date: 21 Mar 2007 00:47:46
From: Barry Jarrett
Subject: Re: tuning a pstat
On Tue, 20 2007 21:53:50 GMT, "Robert Harmon"
<r_h_harmon@Zhotmail.com > wrote:

>I've a Nuova Simonelli Personal a friend gave me. It looks to be in pretty
>good shape & when I bench tested it everything worked - sort of.
>
>Besides the usual suspects; leaks & crud build up, the first thing I noticed
>was that if I aimed for 1.1 - 1.3 boiler pressure the water in the Styrofoam
>cup never exceeds 184F. If I want it to reach 195F I have to set the
>pressure at 1.6 bar. I understand that these gauges are stone-age technology
>but could it be that far off? Also, at 1.6 bar the temp is 196F for the
>flush, 193 & 191 for the next two 1.5 ounce pulls, then drops off quickly
>for subsequent pulls.
>
>I would've thought that, given the boiler size, incoming cold water wouldn't
>drop the HX temps that fast. If HX's are that unstable where are the
>advantages over a single boiler if you still can't pull shots consecutively?
>Is it considered to be enough of an advantage being able to steam & brew at
>the same time?


this is SOP for older simonellis, and the whole reason i got into
machine modification. simonelli once told me that 185F was the
"ideal" temperature for brewing espresso, and if i didn't like the
espresso at that temperature, then there was something wrong with my
blending/roasting.



  
Date: 21 Mar 2007 00:55:04
From: Robert Harmon
Subject: Re: tuning a pstat
Howdy Barry!
Looks like another good candidate for a PID install, doesn't it? Would a
water line running through the boiler before it enters the HX help, or is
that just adding an HX to an HX? Or even a smallish holding tank with a
preheater for water destined for the HX? I'll have to think about this one,
the HX seems to be at least contributing to the problem by dropping temp to
fast.
--
Robert (Gig 'em!) Harmon
http://tinyurl.com/pou2y
http://tinyurl.com/psfob
http://tinyurl.com/fkd6r

"Barry Jarrett" <barry@rileys-coffee.com > wrote in message
news:a3010394m04rbeej9fcpi65frsnhjcm121@4ax.com...
> On Tue, 20 2007 21:53:50 GMT, "Robert Harmon"
> <r_h_harmon@Zhotmail.com> wrote:
>
> >I've a Nuova Simonelli Personal a friend gave me. It looks to be in
> >pretty
> >good shape & when I bench tested it everything worked - sort of.
> >
> >Besides the usual suspects; leaks & crud build up, the first thing I
> >noticed
> >was that if I aimed for 1.1 - 1.3 boiler pressure the water in the
> >Styrofoam
> >cup never exceeds 184F. If I want it to reach 195F I have to set the
> >pressure at 1.6 bar. I understand that these gauges are stone-age
> >technology
> >but could it be that far off? Also, at 1.6 bar the temp is 196F for the
> >flush, 193 & 191 for the next two 1.5 ounce pulls, then drops off quickly
> >for subsequent pulls.
> >
> >I would've thought that, given the boiler size, incoming cold water
> >wouldn't
> >drop the HX temps that fast. If HX's are that unstable where are the
> >advantages over a single boiler if you still can't pull shots
> >consecutively?
> >Is it considered to be enough of an advantage being able to steam & brew
> >at
> >the same time?
>
>
> this is SOP for older simonellis, and the whole reason i got into
> machine modification. simonelli once told me that 185F was the
> "ideal" temperature for brewing espresso, and if i didn't like the
> espresso at that temperature, then there was something wrong with my
> blending/roasting.
>




   
Date: 21 Mar 2007 02:06:36
From: Barry Jarrett
Subject: Re: tuning a pstat
On Wed, 21 2007 00:55:04 GMT, "Robert Harmon"
<r_h_harmon@Zhotmail.com > wrote:

>Howdy Barry!
>Looks like another good candidate for a PID install, doesn't it? Would a
>water line running through the boiler before it enters the HX help, or is
>that just adding an HX to an HX? Or even a smallish holding tank with a
>preheater for water destined for the HX? I'll have to think about this one,
>the HX seems to be at least contributing to the problem by dropping temp to
>fast.

have a look at how the HX is plumbed. is it a thermosiphon, or do
both water inlet and outlet lines pass through the same fitting?



    
Date: 21 Mar 2007 04:58:15
From: Robert Harmon
Subject: Re: tuning a pstat
Howdy Barry!
There are two tubes on the HX inlet; 1) inlet water line, 2) goes to, or
rather it comes from??, group. It looks like this would preclude a pre-HX
HX, so I guess it's another job for PID man.
--
Robert (Gig 'em!) Harmon
http://tinyurl.com/pou2y
http://tinyurl.com/psfob
http://tinyurl.com/fkd6r

"Barry Jarrett" <barry@rileys-coffee.com > wrote in message
news:no4103pj05o2ta0qf7n9qudfmrbm16mff7@4ax.com...
> On Wed, 21 2007 00:55:04 GMT, "Robert Harmon"
> <r_h_harmon@Zhotmail.com> wrote:
>
> >Howdy Barry!
> >Looks like another good candidate for a PID install, doesn't it? Would a
> >water line running through the boiler before it enters the HX help, or is
> >that just adding an HX to an HX? Or even a smallish holding tank with a
> >preheater for water destined for the HX? I'll have to think about this
> >one,
> >the HX seems to be at least contributing to the problem by dropping temp
> >to
> >fast.
>
> have a look at how the HX is plumbed. is it a thermosiphon, or do
> both water inlet and outlet lines pass through the same fitting?
>




     
Date: 21 Mar 2007 05:12:07
From: Barry Jarrett
Subject: Re: tuning a pstat
On Wed, 21 2007 04:58:15 GMT, "Robert Harmon"
<r_h_harmon@Zhotmail.com > wrote:

>Howdy Barry!
>There are two tubes on the HX inlet; 1) inlet water line, 2) goes to, or
>rather it comes from??, group. It looks like this would preclude a pre-HX
>HX, so I guess it's another job for PID man.


you can put as many pids on that as you care, but it won't help at
all.




      
Date: 21 Mar 2007 14:54:23
From: Robert Harmon
Subject: Re: tuning a pstat
Howdy Barry!
I read your posts for an earlier thread where you mention adding length to
the draw tube. Did you happen to take & retain pics of that mod? I'm still
considering putting a coil of tubing through the boiler wall between the
inlet water & the HX - effectively lengthening the HX. I'm thinking that
this will ameliorate the problems of temp fluctuations when pulling multiple
shots.
--
Robert (??) Harmon
http://tinyurl.com/pou2y
http://tinyurl.com/psfob
http://tinyurl.com/fkd6r

"Barry Jarrett" <barry@rileys-coffee.com > wrote in message
news:vkf103tlukn1ho9surv5mqml0quqm82b0t@4ax.com...
> On Wed, 21 2007 04:58:15 GMT, "Robert Harmon"
> <r_h_harmon@Zhotmail.com> wrote:
>
> >Howdy Barry!
> >There are two tubes on the HX inlet; 1) inlet water line, 2) goes to, or
> >rather it comes from??, group. It looks like this would preclude a pre-HX
> >HX, so I guess it's another job for PID man.
>
>
> you can put as many pids on that as you care, but it won't help at
> all.
>
>




       
Date: 21 Mar 2007 17:58:32
From: Barry Jarrett
Subject: Re: tuning a pstat
On Wed, 21 2007 14:54:23 GMT, "Robert Harmon"
<r_h_harmon@Zhotmail.com > wrote:

>the draw tube. Did you happen to take & retain pics of that mod? I'm still

someplace i have a photo of the mod. all i did was solder on a
length of copper tube to the existing copper draw tube. the length
was a WAG.

>considering putting a coil of tubing through the boiler wall between the
>inlet water & the HX - effectively lengthening the HX. I'm thinking that
>this will ameliorate the problems of temp fluctuations when pulling multiple
>shots.

it won't. those machines will start hot and then get progressively
cooler until they flatline at whatever the baseline temp is for the HX
setup. it takes about six doubles in a row to go from too hot to too
cool.





        
Date: 21 Mar 2007 18:31:29
From: Robert Harmon
Subject: Re: tuning a pstat
Howdy Barry!
Gotta tell ya, it's beginning to look like the Bunn ES-1A may have been my
luckiest buy yet. Despite its small boiler (about half the size of the NS
Mac) it's proven to be very temperature stable. I pull shot after shot & the
brew temp never drops more than 6F (none of which I attribute to the PID).
In this regard, it's even better than the Cimbali M32 Classic.

I'm very disappointed in the NS's performance (the Mac I rebuilt had the
same issues). Is there still a problem with newer NS machines? Besides the
LM GS4 (which I believe is obscenely priced), which commercial machines do
you believe hold their brew temps best? I had been telling friends that
pretty much any commercial machine is superior to consumer & prosumer
models, but I guess that's not true, is it?
--
Robert (Disappointed, yet again!) Harmon
http://tinyurl.com/pou2y
http://tinyurl.com/psfob
http://tinyurl.com/fkd6r

"Barry Jarrett" <barry@rileys-coffee.com > wrote in message
news:ias2035uasurjf2n3uug9081u6sbo5n7p4@4ax.com...
> On Wed, 21 2007 14:54:23 GMT, "Robert Harmon"
> <r_h_harmon@Zhotmail.com> wrote:
>
> >the draw tube. Did you happen to take & retain pics of that mod? I'm
> >still
>
> someplace i have a photo of the mod. all i did was solder on a
> length of copper tube to the existing copper draw tube. the length
> was a WAG.
>
> >considering putting a coil of tubing through the boiler wall between the
> >inlet water & the HX - effectively lengthening the HX. I'm thinking that
> >this will ameliorate the problems of temp fluctuations when pulling
> >multiple
> >shots.
>
> it won't. those machines will start hot and then get progressively
> cooler until they flatline at whatever the baseline temp is for the HX
> setup. it takes about six doubles in a row to go from too hot to too
> cool.
>
>
>




         
Date: 21 Mar 2007 19:19:41
From: Barry Jarrett
Subject: Re: tuning a pstat
On Wed, 21 2007 18:31:29 GMT, "Robert Harmon"
<r_h_harmon@Zhotmail.com > wrote:

>Gotta tell ya, it's beginning to look like the Bunn ES-1A may have been my
>luckiest buy yet. Despite its small boiler (about half the size of the NS
>Mac) it's proven to be very temperature stable. I pull shot after shot & the
>brew temp never drops more than 6F (none of which I attribute to the PID).
>In this regard, it's even better than the Cimbali M32 Classic.

i wouldn't call 6F "stable". ;)


>
>I'm very disappointed in the NS's performance (the Mac I rebuilt had the
>same issues). Is there still a problem with newer NS machines? Besides the
>LM GS4 (which I believe is obscenely priced), which commercial machines do
>you believe hold their brew temps best? I had been telling friends that
>pretty much any commercial machine is superior to consumer & prosumer
>models, but I guess that's not true, is it?


my NS was very stable, as long as it was in constant use (as is the
case with many commercial machines). unfortunately, it was stable at
a temperature far lower than i desired, and was not easily adjustable.
very few machines, either commercial or home, have good off-idle
performance. commercial machines are meant to be *used*, and many
will provide good to excellent stability (depending upon what one
considers "stable"... certainly within 6F!) under moderate to heavy
use. let the thing sit idle for awhile, though, and expect the first
shots to be hot (or cool if it's an older zocco). off-idle issues
have been addressed recently, with the newest NS, zocco, and
Synesso machines performing quite well.





          
Date: 22 Mar 2007 00:28:13
From: Robert Harmon
Subject: Re: tuning a pstat
Barry Jarrett <barry@rileys-coffee.com > wrote in
news:fhv203p41cosfj6v96qvfjuqa6n30prjo1@4ax.com:

> On Wed, 21 2007 18:31:29 GMT, "Robert Harmon"
> <r_h_harmon@Zhotmail.com> wrote:
>
> >Gotta tell ya, it's beginning to look like the Bunn ES-1A may have
> >been my luckiest buy yet. Despite its small boiler (about half the
> >size of the NS Mac) it's proven to be very temperature stable. I pull
> >shot after shot & the brew temp never drops more than 6F (none of
> >which I attribute to the PID). In this regard, it's even better than
> >the Cimbali M32 Classic.
>
> i wouldn't call 6F "stable". ;)
>
>
> >
> >I'm very disappointed in the NS's performance (the Mac I rebuilt had
> >the same issues). Is there still a problem with newer NS machines?
> >Besides the LM GS4 (which I believe is obscenely priced), which
> >commercial machines do you believe hold their brew temps best? I had
> >been telling friends that pretty much any commercial machine is
> >superior to consumer & prosumer models, but I guess that's not true,
> >is it?
>
>
> my NS was very stable, as long as it was in constant use (as is the
> case with many commercial machines). unfortunately, it was stable at
> a temperature far lower than i desired, and was not easily adjustable.
> very few machines, either commercial or home, have good off-idle
> performance. commercial machines are meant to be *used*, and many
> will provide good to excellent stability (depending upon what one
> considers "stable"... certainly within 6F!) under moderate to heavy
> use. let the thing sit idle for awhile, though, and expect the first
> shots to be hot (or cool if it's an older zocco). off-idle issues
> have been addressed recently, with the newest NS, zocco, and
> Synesso machines performing quite well.
>
>
>
>


I didn't state that correctly - it should have read 6 degree swing (+ or -
3 degrees F from the set point).