Our Valued Sponsor
OpinionsConsumer ReviewsGuides and How TosCoffeeGeek ReviewsResourcesForums
Espresso: Espresso Mods and Restorations
Saeco rapid steam - mini HX or what?
Rocket R58 Double Boiler
Rocket Espresso R58 Double Boiler -  Everything you need for the perfect shot!
www.seattlecoffeegear.com
 
Not Logged in: Log In to Postlog in
New Topics updated topics   New Posts new posts   Unanswered Posts new unanswered  
Search Discussion Board search   Discussion Board FAQ faq   Signup sign up  
Discussions > Espresso > Espresso Mods > Saeco rapid...  
view previous topic | view next topic | view all topics
showing page 2 of 3 first page | last page previous page | next page
Author Messages
jannus
Senior Member


Joined: 19 Mar 2013
Posts: 66
Location: South Africa, Cape Town
Expertise: I like coffee

Espresso: NS ElliMatic & OLD Via...
Grinder: mazzer sj
Vac Pot: nope
Drip: yup
Roaster: nope
Posted Wed Mar 27, 2013, 1:33am
Subject: Re: Saeco rapid steam - mini HX or what?
 

Hello ddubick,

Thanks for your response!

ddubick Said:

From that breakout diagram you may be right in your analysis of how it's working.  
I would think the brew temp would start closer to steaming temp due to the issue similar to HX's overheating.  And when you say it drops rapidly do you mean just free flowing water or during an actual shot where water volume isn't all that much?

Posted March 26, 2013 link

I initially worked with free flowing water, but limiting it to about 30ml.  Even testing with the warmed up ppf, I can only get about 58 degrees C exiting from the portafilter.

ddubick Said:

There is the possibility that there's scale coating the small 'HX' tube so badly that the heat from the boiler can't get through.  Have you opened the boiler yet?

Posted March 26, 2013 link

I have.  No scale on the outside of the tube.  There was a bit, but not enough to even get close to covering the whole tube.   All removed when I opened it to replace the o-rings.

ddubick Said:

HX's work well because there's a good volume of water in the HX being moderated by the boiler, normal use and flushing.  This thing is working more like a thermoblock than an HX - not very well.

Posted March 26, 2013 link

So it seems indeed...  :(  Maybe that's why it's not an often seen mechanism!
back to top
 View Profile Link to this post
jannus
Senior Member


Joined: 19 Mar 2013
Posts: 66
Location: South Africa, Cape Town
Expertise: I like coffee

Espresso: NS ElliMatic & OLD Via...
Grinder: mazzer sj
Vac Pot: nope
Drip: yup
Roaster: nope
Posted Wed Mar 27, 2013, 2:20am
Subject: Re: Saeco rapid steam - mini HX or what?
 

Hello everyone,

Thanks for the responses!  My comments below:

EricBNC Said:

This is a single boiler dual use machine - these is no thermoblock or heat exchanger inside that boiler - just a way for fresh water to get in from the pump and two ways for it to get out:
1) through the group head (where the portafilter is attached)
2) through the steam wand.
The dual thermostats control the element to raise temps to make hotter than boiling water for steam and cooler water (but still hot) for pulling the espresso.

Posted March 26, 2013 link

D4F Said:

I am not sure if you have your question answered yet.  I found another diagram, very similar, but large enough for me to see.
You have SBDU and I am not sure if you understand how that works.  Sorry if you and the others have already answered as much as you need.  SBDU is single boiler dual use.  One boiler has two thermostats, one for brew and the other for steam, thus the two temperatures of the stats.  The tube that I think confusing in this diagram is not connected on top but connected centrally at the bottom.  Hot water enters the tube at the top and then out the group.  Cold water enters away from the tube, and tends to settle being cold, thus the high pickup. If I see it correctly the cold enters the front side and that is why the tube is bent back away from the entry.  Most SBDUs are similar. If your temperature is off then you need know if the tube is connected in place and then try to find if the thermostat is working.  

Posted March 26, 2013 link

The above all makes sense, except there's only one thermostat...  That's the part that puzzles me.  SBDU with two thermostats I understand, but this is not it.  This thermostat keeps the water in the boiler at about 124 from what I can see.  D4F, the diagram you have there is indeed perfect.  The single thermostat is labelled 25, described as "Termostato 124 C".  The tube labelled 40 is long enough to actually go into nut 39, and (I guess) therefore takes water from pipe 15 via unit 43 when the pump is active.  I checked this tubing position several times when I had the thing apart, that's how I came up with the mini-hx theory.  If it used the boiler water directly, I would have had 120+ degree water exit from the group whenever the thermostat reaches temperature?

I've let the machine sit now for about 20 minutes before letting it run again, and I managed to get about 65 degree water from the portafilter.  Maybe enough for a double before temperature starts dropping.  Maybe that's just the way this thing is meant to be used...switch on, let it sit, pull a double, and let it sit for 10 minutes before doing so again...  The closest to something passable is probably by doing it that way, by my analysis, although it still doesn't bring temperature close to where it should be.

For comparison, on my ancient SBDU with two thermostats, I get about 82 degrees C exiting the group, without major warmup (I just switched it on now to see, took measurement a few minutes after the temp light went green).

cheers,
Jan
back to top
 View Profile Link to this post
calblacksmith
Moderator
calblacksmith
Joined: 25 Nov 2007
Posts: 7,772
Location: Riverside, Ca, U.S.A.
Expertise: I live coffee

Espresso: ECM Vene. A1, La Cimbali M32
Grinder: Azkoyen Capriccio, Major
Vac Pot: 40s era Silex
Drip: Msl. Com. brewers
Roaster: gave it a try, decided no
Posted Wed Mar 27, 2013, 6:07am
Subject: Re: Saeco rapid steam - mini HX or what?
 

D4F Said:

Or on the spell checker :)

Posted March 26, 2013 link

I did that on PORPOUS, oops, I did it agaoion ;P

 
In real life, my name is
Wayne P.
Anything I post is personal opinion and is only worth as much as anyone else's personal opinion. YMMV!

Feed the newbs, starve the trolls and above all enjoy what you drink!
back to top
 View Profile Visit website Link to this post
D4F
Senior Member


Joined: 15 Mar 2012
Posts: 2,015
Location: USA
Expertise: I like coffee

Espresso: Gaggia Classic PID
Grinder: Baratza Forte-AP
Posted Wed Mar 27, 2013, 3:04pm
Subject: Re: Saeco rapid steam - mini HX or what?
 

Speaking of "mistaks" I realize at least part of mine, and I did not do it on PORPOUS.  Sometimes it is easier to follow an apparent lead on a thread than to really figure it out, sorry for the misinformation.  I looked again at the diagram and pictures.  I saw "SBDU" in the thread and then saw the Classico diagram on PartsGuru, two stats, and then saw that I was on the wrong diagram and switched to the Classico RS diagram.  By that time, my brain did not make the switch and I saw the dual stat clip and did not notice the 1 stat.  

I will try again.  There are only 2 lights and 2 switches if I see it correctly.  An on off switch, and brew/pump switch, and one stat.  

Click Here (www.partsguru.com)

Interesting pump outflow with a split.  I cannot confirm from the diagram where tube 40 goes, but I will take your word that it is attached at both ends.  If the pipe is a through pipe connected at both ends then it appears to be Hx.  That said, how does steam, or water, from the wand exit the boiler?  I cannot visualize that from the diagrams.  The top boiler exit seems from your description to be occluded with the central pipe (Hx).  I found an on line manual

Click Here (www.partsguru.com)

The water flow is not described for steam.  When the pump is run water could not go into the tank, no open outlet. That forces water through the tube and out the group.  The valve on your diagram parts 35 plus minus form that valve, typically spring closed to hold back water.  When the steam wand opens, again I cannot see the outlet from the boiler, the pump run would fill the boiler to prime it or get hot water from the wand.  That fits the manual description.  The group valve would keep water from the tube as least resistance is the open wand.

With only one stat, the boiler should get close to stat temperature.  You should be able to approximate that with a digital instant thermometer help against the hot boiler.  If that is very far off, then the stat may be bad.  Scale buildup could blunt the boiler shell temperature also, but IIRC you already looked at or remedied scale.

Does the central bent "Hx" tube seal into the top and bottom?  If so, then how does water or steam get to the steam wand?  I am missing one tank outlet.  Unfortunately my parts diagram is not in english so the parts description does not help.  If it is meant to function as HX, then the tube must have more volume than I think from the diagram, or the incoming cold water would pass through the tube without much warming.  You would get a little hot water, the tube volume, and then cool.  Normal Hx uses a "cooling flush" as the water in the tube can be overheated.  A cooling flush was not described in the manual and the tube does not appear to have the capacity to support that.

Hope that makes some sense and that you can fill in the blanks.

 
D4F also at
http://www.gaggiausersgroup.com/
back to top
 View Profile Link to this post
ddubick
Senior Member


Joined: 1 May 2012
Posts: 146
Location: Calgary, Alberta, Canada
Expertise: I live coffee

Espresso: Nuova Simonelli Appia 1Gr
Grinder: OE Pharos, Macap M5, Nuova...
Roaster: Behmor 1600
Posted Thu Mar 28, 2013, 9:47pm
Subject: Re: Saeco rapid steam - mini HX or what?
 

Just a shot in the dark.

Are you properly 'priming' the boiler before and after steaming as stated in the manual?  This machine doesn't have a boiler auto-fill function or any means to pulse the pump like other saeco thermoblock steamers I've seen so you have to manually fill up the boiler before and after each steaming session.  If the boiler was only partially full it might explain the low temps coming through the 'hx' system.
back to top
 View Profile Link to this post
jannus
Senior Member


Joined: 19 Mar 2013
Posts: 66
Location: South Africa, Cape Town
Expertise: I like coffee

Espresso: NS ElliMatic & OLD Via...
Grinder: mazzer sj
Vac Pot: nope
Drip: yup
Roaster: nope
Posted Fri Mar 29, 2013, 7:40am
Subject: Re: Saeco rapid steam - mini HX or what?
 

Hi D4F,

No problem on the initial miss-steak (on PORPOUS or not!), I appreciate your trouble in looking all this up!  :)

D4F Said:

I will try again.  There are only 2 lights and 2 switches if I see it correctly.  An on off switch, and brew/pump switch, and one stat.  

Posted March 27, 2013 link

correct, two switches.  The power switch has a light, the pump somehow doesn't (or mine is blown).  Then there's the standard stat indicator light.

D4F Said:

Interesting pump outflow with a split.  I cannot confirm from the diagram where tube 40 goes, but I will take your word that it is attached at both ends.  If the pipe is a through pipe connected at both ends then it appears to be Hx.  That said, how does steam, or water, from the wand exit the boiler?  I cannot visualize that from the diagrams.  The top boiler exit seems from your description to be occluded with the central pipe (Hx).  I found an on line manual

Posted March 27, 2013 link

I concur.  The only light I can shed is perhaps on tube 40:  It is not attached at the top, it kind of just sticks up into the nut.  I suspect that that is how water exits the boiler via the steam wand - there is no "seal" there, it just sits a bit above the highest water level in the boiler.

D4F Said:

The water flow is not described for steam.  When the pump is run water could not go into the tank, no open outlet. That forces water through the tube and out the group.  The valve on your diagram parts 35 plus minus form that valve, typically spring closed to hold back water.  When the steam wand opens, again I cannot see the outlet from the boiler, the pump run would fill the boiler to prime it or get hot water from the wand.  That fits the manual description.  The group valve would keep water from the tube as least resistance is the open wand.

Posted March 27, 2013 link

Agreed, that's my guess as well.  Taking into account though that tube 40 does not form a perfect seal at the top, but just kind of sticks up a bit, when the steam wand opens the pressure in the boiler forces a bit of water out via the path of least resistance (the now open steam wand via the gap at the top of tube 40).  As soon as enough water is out, the steam starts flowing from the wand, slowly emptying the boiler.  On the other hand, if the pump is switched on and the wand is open, the water entering the boiler via tube 6 will force out the already heated water in the boiler.  At this point, however, the water is also being pumped via tube 15 (as if into the "hx tube").  I suspect that either the steam wand valve itself blocks this when open, or the "splitter" (looks like it's part 1) restricts flow to tube 15 enough that the path of least resistance is the steam wand via tube 6 and boiler.

D4F Said:

With only one stat, the boiler should get close to stat temperature.  You should be able to approximate that with a digital instant thermometer help against the hot boiler.  If that is very far off, then the stat may be bad.  Scale buildup could blunt the boiler shell temperature also, but IIRC you already looked at or remedied scale.

Posted March 27, 2013 link

Indeed.  I checked the boiler with a thermocouple, as well as a non-contact thermometer.  Stat clicks off when the temperature of the boiler reaches about 120 degrees C, and it clicks on when the boiler reaches about 110 degrees C.  When the pump is switched on, the heater is not activated automatically.

D4F Said:

If it is meant to function as HX, then the tube must have more volume than I think from the diagram, or the incoming cold water would pass through the tube without much warming.  You would get a little hot water, the tube volume, and then cool.  Normal Hx uses a "cooling flush" as the water in the tube can be overheated.  A cooling flush was not described in the manual and the tube does not appear to have the capacity to support that.

Posted March 27, 2013 link

Yup, that's what bothers me as well.   :(  It looks like the tube volume excess temperature is just kind of absorbed into the head etc, so a cooling flush is not really required.  It really does look like raising the stat temperature is the obvious option, but that could bring it a bit close to the thermal fuse also on there, sitting at 150 degrees C.  

If you think that is a worthy shot, I'll give it a bash, but otherwise I should probably just get rid of the machine, and get something else.

D4F Said:

Hope that makes some sense and that you can fill in the blanks.

Posted March 27, 2013 link

Perfect sense, thanks!  :)

Only other option is to convert  this into a normal boiler (SBSU) by cutting tube 40 in half, dropping the stat to 98 degrees or so, and ditching the steam wand.  Of course, if that doesn't give satisfactory results (read "vastly improved results")...the whole thing goes to the bin.
back to top
 View Profile Link to this post
jannus
Senior Member


Joined: 19 Mar 2013
Posts: 66
Location: South Africa, Cape Town
Expertise: I like coffee

Espresso: NS ElliMatic & OLD Via...
Grinder: mazzer sj
Vac Pot: nope
Drip: yup
Roaster: nope
Posted Fri Mar 29, 2013, 7:45am
Subject: Re: Saeco rapid steam - mini HX or what?
 

Hi ddubick,

ddubick Said:

Just a shot in the dark.

Are you properly 'priming' the boiler before and after steaming as stated in the manual?  This machine doesn't have a boiler auto-fill function or any means to pulse the pump like other saeco thermoblock steamers I've seen so you have to manually fill up the boiler before and after each steaming session.  If the boiler was only partially full it might explain the low temps coming through the 'hx' system.

Posted March 28, 2013 link

A good shot!  I am unfortunately priming it as described...  :)  You are correct in that it doesn't auto-fill.  The manual does however specify that after steaming, the boiler should be primed again before brewing.

Well spotted on that one, I never actually considered that a possibility, it's just by following the instructions blindly that I didn't stumble into that trap.  :)
back to top
 View Profile Link to this post
Tomcody
Senior Member
Tomcody
Joined: 4 Apr 2011
Posts: 45
Location: Georgia
Expertise: I love coffee

Espresso: La San Marco Practical 95E
Grinder: Mazzer Mini Timer
Drip: Arçelik 3200 Turkish Coffee...
Roaster: Air Popcorn Popper
Posted Fri Mar 29, 2013, 8:13am
Subject: Re: Saeco rapid steam - mini HX or what?
 

Quick Question.  Does it Steam?  What happens when you try?

 
"Coffee should be black as hell, strong as death, and sweet as love."
"A cup of coffee commits one to fourty years of friendship."
- Turkish proverbs
back to top
 View Profile Visit website Link to this post
ddubick
Senior Member


Joined: 1 May 2012
Posts: 146
Location: Calgary, Alberta, Canada
Expertise: I live coffee

Espresso: Nuova Simonelli Appia 1Gr
Grinder: OE Pharos, Macap M5, Nuova...
Roaster: Behmor 1600
Posted Fri Mar 29, 2013, 8:15am
Subject: Re: Saeco rapid steam - mini HX or what?
 

Do you think that the boiler is stable around 124 deg?  Do you get lots of steam?  

It doesn't make sense that the brew water is so cool considering this thing was obviously designed to work, it couldn't have gone to market without brewing at a reasonable temp.
back to top
 View Profile Link to this post
D4F
Senior Member


Joined: 15 Mar 2012
Posts: 2,015
Location: USA
Expertise: I like coffee

Espresso: Gaggia Classic PID
Grinder: Baratza Forte-AP
Posted Fri Mar 29, 2013, 8:39pm
Subject: Re: Saeco rapid steam - mini HX or what?
 

I still am trying to understand the mechanics.  If the tube sealed at the top, then it would act as Hx, but there would be no steam exit.  Sound correct?

For the boiler to be filled/primed, water goes in until the boiler is full.  Wand is open.  If you close the wand with the pump running, then the water has to fill to the top of the tube and out the tube.  It could be the highest point it it goes up into the nut and partially into the steam outlet.  That might make sense with the concept that when water enters from the top, into the steam fixture with the valve closed it must then go down the tube.  It would mix, since no seal, and give a blend of cool and stat temperature water.  Actually water may enter at both places and blend the output by aiming cool water at the opening and flooding in cool water to the boiler from the side pushing out some hot water with the cool.  Hope that my description makes sense, but the concept does not as there is no obvious control of the blend unless the valve splitter somehot does that, or the correct fit of the tube at the top.  It seems that a plug of the top/steam entering tube would stop the cool water being aimed at the tube and force more boiler water out.  

What do you know about the splitter valve in the line?  Any adjustment?

If you lower or cut the tube it may do the same, less cool and more hot through the tube.  Is the tube height adjustable from below?  Will it seat down further?

Is there any steam control for temperature?  It seems that you turn on the machine and it goes to a set temperature that is too low for steam and too hot for brew unless you are getting Hx or a water blend as described.  Unlike SBDU, no steam switch, just open the wand?  If so, look for different stats.  135C - 140C would greatly improve steaming pressure and raise the blend temperature, perhaps too hot.

Click Here (espressocare.com)

Click Here (www.cafeparts.com)

Click Here (www.jgbhose.com)

PID is the answer to select the correct temperature.  If you like projects, then DIY PID and you can remove it and reuse it, or sell it when you move on.

 
D4F also at
http://www.gaggiausersgroup.com/
back to top
 View Profile Link to this post
showing page 2 of 3 first page | last page previous page | next page
view previous topic | view next topic | view all topics
Discussions > Espresso > Espresso Mods > Saeco rapid...  
New Topics updated topics   New Posts new posts   Unanswered Posts new unanswered     Search Discussion Board search   Discussion Board FAQ faq   Signup sign up  
Not Logged in: Log In to Postlog in
Discussions Quick Jump:
Symbols: New Posts= New Posts since your last visit      No New Posts= No New Posts since last visit     Go to most recent post= Newest post
Forum Rules:
No profanity, illegal acts or personal attacks will be tolerated in these discussion boards.
No commercial posting of any nature will be tolerated; only private sales by private individuals, in the "Buy and Sell" forum.
No SEO style postings will be tolerated. SEO related posts will result in immediate ban from CoffeeGeek.
No cross posting allowed - do not post your topic to more than one forum, nor repost a topic to the same forum.
Who Can Read The Forum? Anyone can read posts in these discussion boards.
Who Can Post New Topics? Any registered CoffeeGeek member can post new topics.
Who Can Post Replies? Any registered CoffeeGeek member can post replies.
Can Photos be posted? Anyone can post photos in their new topics or replies.
Who can change or delete posts? Any CoffeeGeek member can edit their own posts. Only moderators can delete posts.
Probationary Period: If you are a new signup for CoffeeGeek, you cannot promote, endorse, criticise or otherwise post an unsolicited endorsement for any company, product or service in your first five postings.
Rancilio Silvia - How to
Step by step guide for easy brewing and steaming with the Rancilio Silvia
www.seattlecoffeegear.com
Home | Opinions | Consumer Reviews | Guides & How Tos | CoffeeGeek Reviews | Resources | Forums | Contact Us
CoffeeGeek.com, CoffeeGeek, and Coffee Geek, along with all associated content & images are copyright ©2000-2014 by Mark Prince, all rights reserved, unless otherwise indicated. Content, code, and images may not be reused without permission. Usage of this website signifies agreement with our Terms and Conditions. (0.398711919785)
Privacy Policy | Copyright Info | Terms and Conditions | CoffeeGeek Advertisers | RSS | Find us on Google+