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Date: 25 Mar 2007 18:04:14
From: Robert Harmon
Subject: newest "challenge" with NS Personal
I replaced o-rings & gaskets, replaced a few suspicious-looking wires, &
even replaced a copper tube that looked a bit worn. I buttoned everything
back up, descaled it, & backflushed it with detergent, & flushed everything
out with copious quantities of plain water. Using filtered water, I pulled a
few trash shots & then tried one for drinking.

YUCK! There's an unpleasant taste to the coffee; I run a water-only shot &
the water is effervescent & takes 30 seconds or so to clear. There is a
definite smell to the water & it tastes pretty bad too. I pulled some tubes,
start examining things, & I see a soapy residue in the HX outlet.

Hmmm? Isn't the only way something like that could've gotten in there is if
the solenoid didn't work properly? But when I back flushed the machine there
was detergent-laced solution in the waste water, which indicates it did work
(at least a bit). I'll be pulling the solenoid apart after the machine cools
& taking a look see. How is the solenoid coil itself tested?
--
Robert (Old machines are fun, old women are another story!) Harmon
http://tinyurl.com/2tnv87






 
Date: 28 Mar 2007 13:04:15
From: Robert Harmon
Subject: Re: newest "challenge" with NS Personal
On 25, 9:51 pm, Barry Jarrett <b...@rileys-coffee.com > wrote:
> On Sun, 25 2007 21:26:52 GMT, "RobertHarmon"
>
> <r_h_har...@Zhotmail.com> wrote:
>
> >I'm thinking the best way to descale the HX is to disconnect the inlet &
> >outlet & run hot solution directly through it.
>
> on these non-thermosiphon machines, that is only ginally effective
> for descaling. you need to pull the plug from the top of the hx and
> fill the chamber with descaler.

Howdy Barry!
Problem's solved & the water is clean & the shots are sweet tasting.

For some reason I used to think of HX's as being closed-systems - a
tube connected to an inlet water supply that looped through the boiler
& exited into the group. I haven't looked at the HX in the Bunn but if
it's the same as the NS Mac & Personal I'll be lowering my opinion of
these machines.

The NS HX doesn't appear to be any more sophisticated than a Gaggia or
Rancilio single boiler. Incoming cold water seems to mix with the hot
water already in the HX. I don't see any separation of the two.

I hope I'm missing something?
--
Robert



  
Date: 31 Mar 2007 03:52:30
From: Barry Jarrett
Subject: Re: newest "challenge" with NS Personal
On 28 2007 13:04:15 -0700, "Robert Harmon"
<r_h_harmon@hotmail.com > wrote:

>The NS HX doesn't appear to be any more sophisticated than a Gaggia or
>Rancilio single boiler. Incoming cold water seems to mix with the hot
>water already in the HX. I don't see any separation of the two.
>
>I hope I'm missing something?


cold water is injected into the bottom of the HX, and the brew water
is pulled through the tube. the length of the tube helps determine
the brew water temp.

sorry for the delay, but i've been out of town all week w/o usenet
access.

--barry "got maddy's cona, though!"



   
Date: 31 Mar 2007 18:14:03
From: Robert Harmon
Subject: Re: newest "challenge" with NS Personal
Barry Jarrett <barry@rileys-coffee.com > wrote in
news:qjmr035hjtg32dciukhc0k3m7k92j7l3vb@4ax.com:

> On 28 2007 13:04:15 -0700, "Robert Harmon"
> <r_h_harmon@hotmail.com> wrote:
>
> >The NS HX doesn't appear to be any more sophisticated than a Gaggia or
> >Rancilio single boiler. Incoming cold water seems to mix with the hot
> >water already in the HX. I don't see any separation of the two.

> cold water is injected into the bottom of the HX, and the brew water
> is pulled through the tube. the length of the tube helps determine
> the brew water temp.
>

So what you did was lengthen the outlet tube so there was more hot water in
the HX before the cold water was injected? OK, so does the process involve
some mixing of cold water with hot water already in the HX? It doesn't seem
likely that the incoming water totally displaces the hot water without
*some* mixing.

Man, this is technology staright out of the Dark Ages! Surely someone,
somewhere, probably at some time in the distant future, has tried sensors &
injectors to mix hot & cold water to get appropriate temps?

Robert (Amazed at what I'm discovering!) Harmon
--
http://tinyurl.com/pou2y
http://tinyurl.com/fkd6r
Remove "Z" to reply via email.


    
Date: 01 Apr 2007 06:12:19
From: Barry Jarrett
Subject: Re: newest "challenge" with NS Personal
On Sat, 31 2007 18:14:03 GMT, Robert Harmon
<r_h_harmon@Zhotmail.com > wrote:

>So what you did was lengthen the outlet tube so there was more hot water in
>the HX before the cold water was injected? OK, so does the process involve
>some mixing of cold water with hot water already in the HX? It doesn't seem
>likely that the incoming water totally displaces the hot water without
>*some* mixing.
>

given the volume of water used in brewing and the volume of water in
the HX, there would be minimal mixing (if any) of hot and cold waters.
temperatures at the top of the HX ran about 225F, iirc. when i did
the modification, i made the assumption that water at the bottom of
the HX was mains temperature, and water at the top of the HX was at
boiler temperature, and if the existing length was giving me 185F,
then adding X" to the tube would bump up the temperature. it was a
WAG, but close enough for me.



 
Date: 27 Mar 2007 20:15:37
From: Robert Harmon
Subject: Re: newest "challenge" with NS Personal
On 26, 10:31 am, "DavidMLewis" <DavidMLe...@mac.com > wrote:
> On 26, 8:12 am, "RobertHarmon" <r_h_har...@Zhotmail.com> wrote:> Is there a secret to getting the plug out without damaging the threads or
> > rounding off the edges of the hex head?
>
> I wouldn't say "secret" since nothing will make something like that
> easy, but I'd carefully heat the surrounding metal with as close to a
> pin-point torch as you have, just before the attempt. That's about as
> effective a way of breaking free this sort of thing as I know. The
> other big aid is to use an impact wrench of some sort.
>
> Best,
> David

Howdy David!
Thanks, it worked perfectly - if pulling my triceps was your plan. No,
it came out fairly quickly. Does this work on the HX retainer as well?
--
Robert



 
Date: 26 Mar 2007 08:31:22
From: DavidMLewis
Subject: Re: newest "challenge" with NS Personal
On 26, 8:12 am, "Robert Harmon" <r_h_har...@Zhotmail.com > wrote:
> Is there a secret to getting the plug out without damaging the threads or
> rounding off the edges of the hex head?
>
I wouldn't say "secret" since nothing will make something like that
easy, but I'd carefully heat the surrounding metal with as close to a
pin-point torch as you have, just before the attempt. That's about as
effective a way of breaking free this sort of thing as I know. The
other big aid is to use an impact wrench of some sort.

Best,
David



 
Date: 25 Mar 2007 14:30:13
From: c0ffeegeek
Subject: Re: newest "challenge" with NS Personal
On 25, 11:04 am, "Robert Harmon" <r_h_har...@Zhotmail.com > wrote:
> I replaced o-rings & gaskets, replaced a few suspicious-looking wires, &
> even replaced a copper tube that looked a bit worn. I buttoned everything
> back up, descaled it, & backflushed it with detergent, & flushed everything
> out with copious quantities of plain water. Using filtered water, I pulled a
> few trash shots & then tried one for drinking.
>
> YUCK! There's an unpleasant taste to the coffee; I run a water-only shot &
> the water is effervescent & takes 30 seconds or so to clear. There is a
> definite smell to the water & it tastes pretty bad too. I pulled some tubes,
> start examining things, & I see a soapy residue in the HX outlet.
>
> Hmmm? Isn't the only way something like that could've gotten in there is if
> the solenoid didn't work properly? But when I back flushed the machine there
> was detergent-laced solution in the waste water, which indicates it did work
> (at least a bit). I'll be pulling the solenoid apart after the machine cools
> & taking a look see. How is the solenoid coil itself tested?
> --
> Robert (Old machines are fun, old women are another story!) Harmonhttp://tinyurl.com/2tnv87


Robert, Share with me your impressions of the machine. I have a
chance to buy one and would like your input.

j



  
Date: 25 Mar 2007 22:06:41
From: Robert Harmon
Subject: Re: newest "challenge" with NS Personal
Howdy J!
It's a well built machine - good size boiler, well laid out interior with
easily reached components.

After tearing my second Mac-type machine down for rebuild there are things I
DON'T like; priy among my dislikes is the group heating arrangement.
Instead of a thermal siphon arrangement NS uses a pass-through plumbing
technique. When a shot is pulled the hot water passes though the rear of the
group before it hits the filter. Where the TS is always working to maintain
a constant temp the NS technique seems to cause a seesaw effect on group
temps.

It makes a good shot within this limitation that's common to all Mac-type
machines. As Barry (the resident NS guru) Jarrett has pointed out, it's
designed to pull shot after shot in a commercial environment, not sit idle
on the counter at home. Google the archives of this group for comments about
the Nuova Simonelli temp characteristics.

After having my hands on several brands of commercial machines I can say
with some authority that my favorite so far is the Bunn ES-1A. These
machines have all the good stuff, are automatics, fit on the counter with a
smaller footprint, parts are available, and are a joy to work on (best
example access to the control panel; remove a finger nut & it flips down.
Others require removing several screws at least to do the same thing.)
--
Robert (Gig 'em!) Harmon
http://tinyurl.com/2tnv87

"c0ffeegeek" <jerry.may1@gmail.com > wrote in message
news:1174858213.207930.265390@d57g2000hsg.googlegroups.com...
> On 25, 11:04 am, "Robert Harmon" <r_h_har...@Zhotmail.com> wrote:
>> I replaced o-rings & gaskets, replaced a few suspicious-looking wires, &
>> even replaced a copper tube that looked a bit worn. I buttoned everything
>> back up, descaled it, & backflushed it with detergent, & flushed
>> everything
>> out with copious quantities of plain water. Using filtered water, I
>> pulled a
>> few trash shots & then tried one for drinking.
>>
>> YUCK! There's an unpleasant taste to the coffee; I run a water-only shot
>> &
>> the water is effervescent & takes 30 seconds or so to clear. There is a
>> definite smell to the water & it tastes pretty bad too. I pulled some
>> tubes,
>> start examining things, & I see a soapy residue in the HX outlet.
>>
>> Hmmm? Isn't the only way something like that could've gotten in there is
>> if
>> the solenoid didn't work properly? But when I back flushed the machine
>> there
>> was detergent-laced solution in the waste water, which indicates it did
>> work
>> (at least a bit). I'll be pulling the solenoid apart after the machine
>> cools
>> & taking a look see. How is the solenoid coil itself tested?
>> --
>> Robert (Old machines are fun, old women are another story!)
>> Harmonhttp://tinyurl.com/2tnv87
>
>
> Robert, Share with me your impressions of the machine. I have a
> chance to buy one and would like your input.
>
> j
>




 
Date: 25 Mar 2007 20:22:28
From: Barry Jarrett
Subject: Re: newest "challenge" with NS Personal
when you descaled, did you descale the hx, too?



  
Date: 25 Mar 2007 21:26:52
From: Robert Harmon
Subject: Re: newest "challenge" with NS Personal
Howdy Barry!
I'm learning a lot more about NS Mac-type machines than I ever really wanted
to know. But it's fun at the same time, so I must be learning something.

Yes, I pulled a lot of solution through it too. But I back flushed after
descaling & flushing the water system. I've never heard of having detergent
getting past a solenoid before, have you?

I'm thinking the best way to descale the HX is to disconnect the inlet &
outlet & run hot solution directly through it. Would that work better than
using the pump to pass it through the system? Other than using gravity what
would be a good way to do this?
--
Robert (Gig 'em!) Harmon
http://tinyurl.com/2tnv87
"Barry Jarrett" <barry@rileys-coffee.com > wrote in message
news:1gmd035a0f5ud92hthsqmsvipq35eiss2p@4ax.com...
> when you descaled, did you descale the hx, too?
>




   
Date: 26 Mar 2007 02:51:30
From: Barry Jarrett
Subject: Re: newest "challenge" with NS Personal
On Sun, 25 2007 21:26:52 GMT, "Robert Harmon"
<r_h_harmon@Zhotmail.com > wrote:

>I'm thinking the best way to descale the HX is to disconnect the inlet &
>outlet & run hot solution directly through it.

on these non-thermosiphon machines, that is only ginally effective
for descaling. you need to pull the plug from the top of the hx and
fill the chamber with descaler.



    
Date: 26 Mar 2007 15:12:44
From: Robert Harmon
Subject: Re: newest "challenge" with NS Personal
Howdy Barry!
Yeah, that's what I was thinking too, but was hoping to avoid. We had one
machine that had a leak in the HX & when we tried pulling the plugs out the
plug threads were bonded to the threads on the boiler. It made a Hell of a
mess of the boiler & we invested a day & a half just repairing the damage.
Is there a secret to getting the plug out without damaging the threads or
rounding off the edges of the hex head?

BTW, I really appreciate your help with these older commercial machines. If
it wasn't for you these would've probably ended up in the landfill.
--
Robert (Keeps 'em working!) Harmon
http://tinyurl.com/2tnv87
"Barry Jarrett" <barry@rileys-coffee.com > wrote in message
news:t6de03l5lsuplp95n5s3el8tcd78t4lqff@4ax.com...
> On Sun, 25 2007 21:26:52 GMT, "Robert Harmon"
> <r_h_harmon@Zhotmail.com> wrote:
>
> >I'm thinking the best way to descale the HX is to disconnect the inlet &
> >outlet & run hot solution directly through it.
>
> on these non-thermosiphon machines, that is only ginally effective
> for descaling. you need to pull the plug from the top of the hx and
> fill the chamber with descaler.
>




     
Date: 31 Mar 2007 03:54:27
From: Barry Jarrett
Subject: Re: newest "challenge" with NS Personal
On Mon, 26 2007 15:12:44 GMT, "Robert Harmon"
<r_h_harmon@Zhotmail.com > wrote:


>Is there a secret to getting the plug out without damaging the threads or
>rounding off the edges of the hex head?
>

if something doesn't budge with moderate force on a regular wrench,
then i reach for the impact wrench and the correct socket (not all
fittings are metric, btw).


--barry "and then the flaming wrench"