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I have had my Silvia v4 for about 10 months and I am looking at upgrading to a Expobar Minore V4 with a PID rather then installing a PID on the Silvia.
What is the benefit of the dual boiler or the HX? What is the difference? From what I read, they do the same thing.
I am looking for a machine to have a PID, any recommendations aside from the Expobar?
Thank you for the link, interesting read.
You don't seem to have much in the range $2k - $3k in dual boiler. Is there a reason for this?
I'm no expert but my understanding is that the kind of technology a HX uses makes having a second boiler unnecessary. They both can do milk and coffee at the same time. I have an HX and the heat is very stable. It seems this is the more popular choice but others can probably shed light on exactly why.
+1 DustyRusty. The HX e61 group and its thermo siphon is a brilliant design. A really well made HX will produce excellent coffee. There is around a $1000 jump to a good double boiler with a rotary pump and PID controllers on the two boilers. It is a case of diminishing returns. In your thoughts plan for a grinder that is top notch. The espresso machines are limited to the quality of the grind. I make coffee for various folk after their yoga sessions using a HX Giotto Rocket v3 with a M4D grinder, it is brilliant coffee, the folk love it. I make ~10 cups at a time. Better than anything local they say - sugar not needed!
Now I caught the dread 'upgraditis' and was in a position to buy a R58 for home use. It is just different. The coffee is excellent. it would be better at work making the multiple coffees with the two boilers than the HX, we'll see.
Both machines are really great.
I also started with a Silvia v1.5 but the HX was a quantum jump. So easy, so consistent, no words to describe the difference.
ECA looked at the Domobar Junior DB, but it didn't cut it in terms of performance expectations for the Australian market...
No doubt Charlie has done his due diligence and it will work well for tight spaces.
The Pro300 sounds similar to Breville Dual Boiler in some ways
Well, I guess they both have two boilers; after that I think nearly all the similarity ends...
One difference with a DB machine is that the steam boiler can be turned off (depending on what you buy) if you want to only use it for espresso. This function will save you some power usage.
Is a PID an essential requirement, if so, why? You can get good temperature control from a well set up HX machine, unless you want to start making huge changes to your brewing temperatures.I am looking for a machine to have a PID, any recommendations aside from the Expobar?
Good luck with your decision.
Didn't think my bias showed, is it that obvious?
As for cooling flushes, I seriously doubt it.... If you had a cooling flush with an EVO, you had HX stall due to a maintenance item- most likely group pistons and this can happen with any machine. Rocket are set for Australian conditions and work brilliantly. On the other hand, if it was a grey import....
Best not let punters come to incorrect assumptions. There is plenty of other misinformation on the internet for those who are easily led.
As someone who just moved off a HX without a PID (Lelit Mara) to a DB with a PID (R58) I must say there is no great gain with the PID. The HX and the DB both made amazing coffees but I'd say the difference has been in the quality of the grinder I am now using.
Other differences worth considering is (in my uneducated understanding) most HX machines have a vibration pump which are noisy whilst most quality DBs have a quieter rotary pump. I'm sure there are exceptions to these statements.
Quality of build and serviceability is another consideration.
My breville dual boiler at 6am sounds great. As long as you like the sound of power drilling through masonry? 😆
Quality in "quality DBs" is the operative word!
It can be tweaked by the user so it's unfair to say it's a grey import thing.. I experienced it on a previously owned hx and it was not a grey import. Not a hard thing to solve.
Upon further 'research', it seems that Rocket Evo 2 should have a standard restrictor in place, even in the US. https://youtu.be/KJwq4wR8vds?t=7m55s Well, another possibility is Rocket intentionally screwing up our US counterpart by using an unoptimized restrictor?
And the above result was with Rocket Evo 2 with following procedure - it still seems to run hot after idles and run cold if you pull shorter than 2 minute interval?
The shot sequence for Evo in the above chart:
5 min later ->97C
2 min later -> 96C
2 min later ->96C
1 min later -> 95C
1 min later -> 94 C
1 min later ->93 C
30 sec later ->91.5C
30 sec later -> 90C
30 sec later -> 90 C
Attached is the link to a lesser quality Bee Ville's temperature profile:
1 min interval - 4 consecutive shots, across 4 random machines - the max and min temperature span is 92.1-93.4C:
So two statements need proving really......(i) only Oz-official import HX has a restrictor in-place (ii) Optimized HX is as stable as a dual boiler
Give me a SCACE, a couple of restrictors with different hole sizes (if not just blank with drill), and 2 working days. I can optimize a whole container of HXs for you (provided the production quality is consistent across different units on the same model). The name might be Rocket, but it's not rocket' science.
Thermosiphon technology is around for long, it's the same technology used on Londinium. If it can be done on Londinium, what makes it exclusively only to Oz's machine? Hence my questions...
Really it's quite simple...all I am asking for is some evidences behind the 'claims'. It'd save my money because I don't have to spend more on a DB, and I am more than happy to support a local business.
Last edited by MadForCoffee; 21st June 2016 at 06:54 PM.
I am certainly no expert on the topic, but I do own a Profitech Pro 500 which was purchased and setup in Australia.
I don't have a method of measuring temperature however, I can say that I have never seen any flash boiling on cooling flushes even when it has been idle for up to 6 hours. I have also experimented with running no cooling flush vs big cooling flushes to establish difference in shot taste and quality, and in my opinion there wasn't really much impact.
I'm not saying that temperature doesn't change as it would be impossible for me to quantify, but I can definitely tell you it doesn't reach any extremes as I have experienced in other HX machines.
Is it possible for any sponsors to kindly share some graphs re stability, pretty please? Picture/graph really speaks a thousand words in this case (and will help sales so I don't see why not). Sorry for being persistent but I would like to put this to rest and be happy with an optimized HX (a bit of OCD here I know but when you are going to spend 2k+ you probably will..).
I agree that an optimized HX won't show flash boiling (because the E61 head runs cooler with the restrictor and the water get cooled down before it has a chance to flash boil). But absence of flash boiling does not necessarily translate to a consistent temperature. Anything below 98C won't show flash boiling as the Rocket Evo graph indicated above.
It is a huge decision factor for HX vs DB - because an optimized DB definitely shows less than +/-1degree C for random walk-up & continuous shots. However, no HX has been proven to be able to deliver that (except that the fact that they don't flash boil).
Well, I don't have any graphs for you but I can give you my view on the topic.
The better Australian retailers and importers are certainly not lying to you when they say they have specifically tuned their machines to perform to expectations and preferences of Australian coffee drinkers. Just last week I looked at a domestic E61 machine that may make it to market here in Oz through a site sponsor, if we can get it to perform to our satisfaction. As received, it ran crazy hot, the pump pressure was maxed out and there were some fit/finish and vibration/noise issues that needed to be dealt with. Our requests and specifications, including thermosyphon restrictor, pressurestat setting and OPV setting, will now go back to the factory to be pre-fitted to Oz machines if they do indeed make it to import.
Now this machine comes from a well established Italian manufacturer that has been building domestic and commercial machines for decades, more than half a century in fact. Of course they know what they are doing, they just don't know what the vast majority of us here want, prefer or care about. The fact that retailers have this sort of relationship with manufacturers, for what is in the end a very small market, is awesome.
Some notes concerning thermosyphons and dual boilers.
Thermosyphon systems ( most conventional heat exchangers) are both beautifully predictable and frustratingly capricious. For their elegant simplicity, they work extremely well. I think of it in terms of an electrical circuit, with a power source (boiler) and a load (group). The power source generates energy, and the load dissipates it. There are a number of factors that influence the stability and speed or energy of the circuit. Some of these (over and above the initial design) can be regulated or pre-set, like boiler pressure or restrictor size, some cannot - like internal condition of the pipes (scale buildup etc), loss of pressure through leaks or defective valves, or external conditions - temperature, very high use, placement near an open door or window, etc. The list goes on. It is an astoundingly simple yet confoundingly complex set of parameters.
So for those reasons, heat exchangers can and do change their performance with usage habits, age and condition of the machine, time of year, placement in a room. Sucks but there it is. Now, shock horror - most domestic dual boilers feature a thermosyphon too! Think about it, it's still a boiler (heat source) physically removed from a group (load). The only real difference is that the heat source is discretely controlled. As in a conventional thermosyphon however, the above mentioned factors can still degrade it's performance, without necessarily being compensated for by the controller. Then there's temperature setpoint offsets, but I'm not even going there.
So all that boils down to is that this notion that dual boilers are somehow infallible and traditional heat exchangers are flakey and contrary is not always, heck even often, true. Sad fact is it DEPENDS. Depends how well the machine was designed and specified in the first place, how well it was calibrated, how well it was maintained, and how it is driven.
I'll finish by saying one of the most temperature stable and predictable machines I've ever measured was a Faema President built in 1964 and using the original E61 groups and heat exchangers.
PS. as MrJack said above, graphs of extraction temperature are meaningless without a comparable flow rate, which is a whole other topic. I'll also happily generate said data if someone wants to put forward a candidate machine(s) and compensate me for my time!
Last edited by coffee_machinist; 23rd June 2016 at 12:17 AM. Reason: semantics
Nice post Rick, good to read the details from an experienced professional.
This sort of leads in to the question of what is a good, functional design for a single/dual boiler group. My thoughts are that the current trends of the major manufactures to go with an e61 style group on single/dual boiler machines is degrading the machine capabilities. The e61 is radiating away heat, takes a long time to heat up and is dependent on external temperature. I am starting to think that they are just for show with no real advantages. They make sense for heat exchanger types that have overheated water cycling and then radiated away by the group.
Surely a single/dual boiler with group directly below the boiler and insulated around the sides is a better design that will heat up faster and be more temperature stable.
The Streitman CT1 shares some of these elements. Its beautiful.
Rick, thank you for your thoughtful explanations. It does raise more questions than answers.
I am not saying the retailers are lying. I believe some tuning has been done for the machines imported into Australia, but I tend to believe there's always some gotcha/puffery (as some said) involved in the statements. Now I see two (i) if you brew at different flow rate, your brew temp would be different - would DB have the same flowrate issue? (ii) Different environments/ambient will affect the performance of the brew temp. Coupled with the other gotchas you have just mentioned, how can one claim it is consistent under the influence of these factors... So my take home message is these optimized machines do not overheat, but the temp stability/repeatability will depend and vary. Is that reasonable?
As for the E61 HX that runs hot, it's all too common. That has been the default configuration for so long - even in Australia and not limited to grey import. It seems more like a specification requested to the manufacturers. In the US, VBM is one of the the firsts to have restrictors installed (years ago), and now others are catching up (Rocket Evo & ECM Technika, may be more I am not sure).
My previous impression was, these temperature measurement is a routine for reputable coffee retailers? Each machine is supposed to be bench-tested. Was that limited to just plugging in the machine and pull a shot without any technical checking (ie using SCACE etc).
Another question went unanswered is : can an optimized HX pull at 93C without any sort of flush (that was the claim)? On the ECM Technika fitted with restrictor, a short flush(1-2 sec) is still needed to purge the initial water to get to target temp. Has Australian machine been configured to eliminate that all together? How about the recovery time (I suppose this is another gotcha)?
Google for: "Why is properly 'calibrated' thermosiphon not standard on E61 HX (in other parts of the world)? " 😀
Probably lacking a bit of respect for the coffeesnobs forum and the people that have put time into providing answers to your question...... 😈
As consumers, don't we have the right to get unbiased responses/feedback? If it comes to that (respect issue), I am just stating what I see as it is - no disrespect intended. There're a couple of people here that I fully respect (Rick is a legend that I respect 200% for instance). For what it's worth, this seems to me more like a sales forum and I am asking for clarification for the statement behind the claims. See the latest WTB: Heatsnobs thread. To me, it seems that any discussion that does not lead to sales/benefit of the forum/sponsors are frowned upon - and there're always a few prominent posters that jumped on the poster in agreement no matter where you go, or if you hit their buttons. No where have I seen such blatant indirect censorship. Andy has done a great job with the Heatsnob invention, but there is no need to censor other discussions (let it takes its own course and eventually they will come to appreciate how much Andy has put into the Heatsnob invention).
Just buy a dual boiler dude. You'll never appreciate an HX. I like my HX, I'm fascinated by its operation, and enjoy its engineering. And I'll take any variance it may have - cause it just does not make a difference to the taste of my coffee in any noticeable way. If you can discern that difference - buy an expensive machine that'll satisfy you. A GS3, Linea mini, Slayer, whatever will make you happy.
If you don't want puff, why are you asking those that sell/service machines to further explain themselves? Go look at the e61 group diagrams, read articles, do your own research and make your own decisions. Trying to back a sponsor into a corner to say something that they don't agree with just to appease you is no real help at all.
Nothing is a "gotcha", it's just a compromise of engineering between capability and affordability, which you as a consumer get to make a decision about. It's your responsibility to discern through the sales pitch.
I did all this when I bought my e61, and am now satisfied I made a decision for myself. If I didn't like it now, I'd only have myself to blame. But I love it. Take responsibility for yourself and enjoy your research, and enjoy the product you buy. The information is all out there for you, but of course you have to interpret some of if for yourself. There are no absolute facts, just human representation of facts.
No information is free. It cost someone something.
After reading some of the posts in this and other recent threads I wonder about the title of this forum (Coffee Snobs) perhaps for some members (Coffee Machine Snobs) would be a more fitting title.
The only reason I'm a member here is for the simple reason that I enjoy better than average coffee, I've owned a machine for many years that is very capable of dispensing exactly what I want, provided I feed it with the appropriate fodder it performs like a star, shot after shot, day after day and year in year out.
On the other hand we see this preoccupation by some with the minutia of machines and grinders to the point of obsession, perhaps they feel that having a machine tuned to run like an atomic clock will compensate for the deficiencies in their own technique, or, is it simply a case of bragging rights and desire to keep up with the Jones's, regardless of the psychology it all seems like an expensive exercise in futility
As far as coffee quality is concerned, I've had countless shots made on so called, top end machines that should have hit the sink, given any decent espresso machine is well maintained, a knowledgeable operator with a supply of quality beans will be able to produce a brew that will meet my standard, and I imagine 99% of other espresso aficionado's
My passion is good coffee, until my equipment shows signs of not meeting my needs I'll stick with it.
Unsure why, but the term anal - retentive springs to mind.
For a while, I became a bit obsessed with getting planets aligned to make every shot is a so-called god-shot and drooling over equipment that cost big $s.
Then one day I realized i already do make brilliant coffee. OK, not every shot is perfect (but that is an arbitrary standard) and some days I make sink shots. But my equipment is good enough.
But I still like the idea of owning a machine that will allow you to tweak a few settings to get the best out out of the coffee rather than settling for 'near enough'. Damn, I'm drooling again.
Perhaps the way MadForCoffee puts things can sound a little disrespectful. Even still, I would have thought asking questions (maybe a bit more diplomatically) forms part of good research. Agreed, information is not free, but neither is it compulsory to offer any, and it should be appreciated when it is (which is perhaps the source of some of the frustrated messages).
However, still an interesting conversation and valid topic title. Sponsors comments and their reasons are just as legitimate as end users, and good to hear from both sides.
Some of the obsessive questioning into the minutia of operations may be pointless but should it be stopped? I think some useful points have been made (eg apart from large thermal mass, is there a reason for E61 style groups on single, or double boilers?) Keep it going (respectfully) I say.
Holy moly!! I've just read this whole thread and it's been quite an interesting read. There's gotta be thousands of pages of 'free' information on this forum and yet when someone doesn't get handed exactly the (pointless) info they want on a silver platter they get their knickers in a knot. Sure, sellers are making modifications to locally sold equipment and claiming it's an improvement. It's not like it's on any billboards though and probably wouldn't even come up in a typical sales interaction in store (unless the customer asked of course). The whole 'as a consumer we have a right to know thing' really grates with me. What's the point of knowing something you don't understand? I know a lot more about coffee machines than I did a few years ago, but some graphed performance results would be pretty meaningless to me as I'm not a machine tech. And who's to say the graphs were a true reflection of reality anyway? So you're still taking the seller on their word. And of course graphs don't account for the 2 biggest variables - the environment and the USER. (As Rick pointed out). Many, if not most pieces of modern technology that we use are specced for local markets, the cars we drive every day being the obvious example and I bet most people don't ask for graphs and tech data to prove the effectiveness of local specs when they're at the car yard shopping for a new car. Still, I suppose if somethings that important to you maybe you could take some time out of your day to pick up the phone and talk to a few of these sellers, or even go and see them in person (does anyone still do that these days?).
I think some of the comments directed toward MadForCoffee are a bit harsh. Perhaps I've missed something, but I dont think it's a lot to ask for data quantifying improvements made - even if only for intellectual curiosity, but particularly so when they are used to advertise your product. If you have favourable data, why would you withold it?
The reality is, holding knowledge silos is no longer a viable business model, the internet is full of people willing to give their (often very substantial) knowledge and sometimes skills away - for free. Just because.
I'd bet specialty coffee industry itself has actually benefited quite a lot from it too (where would we be without open source technologies?).
Sure, this is a sponsored forum, owned and maintained by Andy (many thanks btw), but frankly it is all but insulting to imply that that is all it is. Without the wider community who frequent and contribute here, what would it be?
It's also rather insulting to suggest that users won't understand the information, and that this in an of itself is justification to withold it. Coffee is complex, but it's not complicated.
I suspect that part of the reason there is so much dogma in coffee, is that many people (including many professionals) don't really understand all of the detail (noone does). Part of why I like forums like this is the diverse backgrounds of the participants.
That said, this post isn't really directed at the sponsors in this thread. Generally, I think they are quite open and forthcoming with information and advice. Sure, I'd like to see the data, for interest sake (I'm guess I'm just that nerdy) - but perhaps it just doesn't exist in a nicely bundled, neatly formatted "here you go" form? But is it rude to ask for it?
To those who think the sponsors (and Andy) need defending (they are perfectly capable), or who would diminish the significant contribution from the many many members who are not sponsors - this is a community, communicating via the internet. Nobody owns us.
p.s. apologies for the lengthy post - it's a long train ride home from the pub
Well, I did not disappear, but just to give myself time to calm down before I respond emotionally like what tends to happen.
There're a few clarifications I have to make:
i) I have a DB (Minore with vibe pump) and have been thinking of upgrading (just pure upgraditis and equipment envious). Then there're some statements that say a well tuned HX can be as consistent as a DB. That certainly intrigues me. Why? There're some well built HX I would love to have. But the reason that held me back was I did not want any sort of flush (my past machine was a Cimbali that runs hot like crazy and a VBM, that is less hot, but requires a short flush) and so that ruled that out for me. Coming from a DB, I certainly did not want to 'downgrade' as I wasn't convinced with what was said. So, I've asked.
ii) Doing my own research - yes - I did that, and trust me, I have done probably more than I should (that was why the hole got deeper and deeper). Not expecting spoon-feeding at all and many unfounded/unfair assumptions were made about me. The only place I've seen to claim that optimized HX that doesn't require flush and still able to hit the temp consistently was CS. It was all anecdotal statement for I could find. So, I've asked for some evidences.
Free information - yes and I am grateful. I've learned a lot from those (which also costs me because of upgraditis ). Rick's post above is a gem for example and is the type of posts that I appreciate. I am more a technical person and thus can greatly relate to that. Anal? To some yes. The reason I am here is to learn and to share/give back if I can (not just to boast how good my coffee is or to small-chat around - not the main intention anyway - as I do perceive forum as a place for intellectual-exchange)
iii) I am not pushing sponsors into corner to say what they don't want. I was taking their words for it and trust it is something can be done. My previous understanding was it is a common routine/practice to check the temperature performance for a machine (especially when you imported a whole container of machines, it is common sense to bench test at least some randomly chosen units). For HX- you want to check if the restrictor was the right specification anyway. For DB, you do want to check if the PID offset was correct from the factory. So it doesn't seem like an impossible task to my opinion (and of course it seems I was wrong for assuming).
If it is a compromise, well, I understand and that was my previous understanding too (but it was certainly presented the other way - and again, that's the reason I've asked for clarification). So may be that just means I have misunderstood what was presented/said about the consistency expectation. When something goes against your *not-so-common* common sense or your previous understanding, you tend to question (in a good way). No one would go around posting information/statement that can't be supported right? That'd create a havoc and a world full of myths.
iv) Well, about the post on the other forum, I was being a little sarcastic (I am sorry if that offended anyone). But as I was saying, it is exactly what I'd observed here. You will see the trend here after hanging/lurking for a while. Always when there is some controversy/questionable, there're always a group of posters that jump simultaneously in agreement - there's us and there's them that don't agree with us. I find this 'culture' rather inhibitive to any open discussion - as there is fear for offending the posters that are 'right'. Like how in this thread I was asked not to be so anal or to question what sponrsors have presented, and accept it as it is. Many has done that (and you don't see them posting), but in my opinion no real learning is occuring because you're just taking the information as is and don't understand what's going on.
I agree with you , MrJack
This is a fine forum and thanks to those who comment and assist.