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Thread: Thermoblock versus Boiler

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    Thermoblock versus Boiler

    Gene Cafe Coffee Roaster $850 - Free Beans Free Freight
    I am interested, for interest sakes just how good thermoblock machines are at making espresso and lattes. I know anyone with a boiler machine will put these machines down so I guess I am asking owners past and current how they find these machines.

    Curious, I am.

    Grant

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    Re: Thermoblock versus Boiler

    I was priveleged to be part of a judging panel that tested 10 different brand / model machines in all different price brackets a couple of weeks ago and the results were interesting....if for no other reason, it showed us (I think) that it is not so much a question of thermoblock VS boiler, but a question of comparing rather, the result (or "performance") obtained (ie coffee & steaming) from the "working end" of any individual model.

    So what I am saying is, some boiler machines "produce" better than others, and some thermoblock machines "produce" better than others, and some boiler machines "produce" better than some thermoblock machines, and vice versa, and there are different pricing brackets to all!

    Some machines just perform better than others...irrespective of their internals....

    Having basically just said such nice things about thermoblock machines in general, I will personally remain biased against anything that has its guts made of aluminium (sorry, but aluminium, HEAT and water dont mix....atleast not in my stomach).

    Notwithstanding, dont forget the other caveats such as the fact that in general, most thermoblock machines are "electrical appliance" brands and their long term repairability including availability if parts and / or availability of service agents is suspect compared to the fact that in general, most of the "better" and / or more expensive domestic machines branded or manufactured through traditional coffee machine channels are boiler machines and whilst this has nothing specifically to do with the thermoblock VS boiler thing, this group of machines has good long term repairability and availability of parts and repairer networks....so is still related to the discussion overall.

    Regardz,
    FC.

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    Re: Thermoblock versus Boiler

    Grant,

    with a bit of tweaking (removing the dual-wall crema-killing baskets, super heating hte thermoblock by running steam for about five minutes prior to running a quick cooling flush, then brewing etc etc), my little sunbeam has performed wonderfully. BUT it only performs wonderfully for one drink at a time. Dont even consider steaming enough milk for two lattes - theres simply not enough power in the steam to do this effectively and efficiently, if youre after microfoam and latte art.

    On tuesday nights, theres a Bible study group at my house, and to make about four milk drinks (a mocha, a latte, a double cap and a hot chocolate for my wife) it can take up to 20 minutes. Bring on the HX!

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    Re: Thermoblock versus Boiler

    Quote from mattyj:
    On tuesday nights, theres a Bible study group at my house, and to make about four milk drinks (a mocha, a latte, a double cap and a hot chocolate for my wife) it can take up to 20 minutes. Bring on the HX!
    Hi mattyj,

    Ive got a good boiler machine and making Lattes for four would take me at least 20 minutes from start to slurp. ;) Maybe I need to sharpen up my act a bit...

    Cheers,
    Mal.

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    Re: Thermoblock versus Boiler

    Quote Originally Posted by Mal link=1118073813/0#3 date=1118124645
    Quote from mattyj:
    Ive got a good boiler machine and making Lattes for four would take me at least 20 minutes from start to slurp. ;) Maybe I need to sharpen up my act a bit...
    Wow that would leave some relatively cold coffee at the end.

    I make them 2 maybe 3 at a time (based on volume of milk to be steamed) which would have 4 done in 7-8 minutes at most.

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    Re: Thermoblock versus Boiler

    This is the big difference between a consumer machine and a commercial machine. The ability to pull continous shots and steam at the same time.

    Java "Believes in over-kill" phile

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    Re: Thermoblock versus Boiler

    Hi Wired,

    Usually Im the one to end up with a "warm" brew or Latte since I have to clean up before joining the throng (all shots are doubles). I guess of that 20 minutes, probably 8-10 minutes is cleanup time... never had any compaints from the recipients and I dont mind having the occasional warm one as the company is always welcome and stimulating. Still tastes great though :D :) :-*

    I notice that you have a rather special HX machine though Wired and this should halve the usual prep time compared to a single dual purpose boiler machine like Silvias, Mokitas and their ilk. Ahh, maybe one day I can aspire to owning a similar machine, probably a pipe dream though. Dream on McDuff... ;D

    Cheers,
    Mal.

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    Re: Thermoblock versus Boiler

    my concern about thermoblocks is the steam production - not the quality (run it for long enough, and its incredibly dry), but the quantity and force of the steam.

    IME, thermoblocks simply cant produce powerful enough steam to cope effectively with more than one (maybe two) standards drinks at a time.

    While a dual thermoblock machine might enable the user to pull shots and steam simultaneously - is the steam production powerful enough to keep up???

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    Re: Thermoblock versus Boiler

    but a dual boiler machine might be nice! ;D

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    Re: Thermoblock versus Boiler

    Its been an interesting weekend, pairing a mazzer mini with my sunbeam - while some have said that they speak different dialects, Ive been drinking the best espresso ive ever had - making sure the machine is running hot (doing the steam for a few mins trick mentioned above).

    While the SB and smaller boiler machines may have shortcomings with speed/steam production etc etc, its shown me that the grind is the key factor. As long as the water is delivered at a reasonably consistent temp and pressure, and as long as youve got the distribuition and tamp down pat, its cool - but getting a good grind seems to be the key. With my old delonghi, espresso was good, not great. With the mini maz, its been amazing!

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    Re: Thermoblock versus Boiler

    Hi,

    I started this thread some time ago.

    Still no one has really studied a thermoblock wrt temperature stability.

    The EM6900 has now come along and seeks to position itself amongst the better quality boiler based machines. This machine is really the first one where people really serious about espresso, might consider a thermoblock machine ie. well built (apparently), fully featured (lots of buttons for predetermining pour volume), twin stainless steel lined thermoblocks (holds out promise of HX level performance) and also a particularly well written manual. It is also available at a reasonable price point of $599.

    I know some people think if it tastes good then the machine is OK and taste is really important. The only problem with taste is that it is incredibly subjective. If you really wanted to test something based on test then you would need a blind taste test for the same bean on different machines and using several different palates!!

    The temperature test is also a reliable measure as an espresso machine is just something to supply water at a certain temperature and pressure to the coffee. Really very basic so measuring temperature variation during a shot should give a very objective measure of the machines ability to produce good espresso.

    Some people seem to be able to readily pick out a 8 degree or so variation in temperature during a pour. This variation is likely to be much more noticeable in a side by side comparison with coffee done in a machine with a much more stable temperature profile. Some experience baristas could probably pick out even a second crack variation although I doubt many of us could do that.

    I guess that might be a reasonable goal then second crack, something easily achievable with the right technique on most boiler/HX machines.

    Grant


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    Re: Thermoblock versus Boiler

    Quote Originally Posted by mattyj link=1118073813/0#7 date=1118196365
    my concern about thermoblocks is the steam production - not the quality (run it for long enough, and its incredibly dry), but the quantity and force of the steam.

    IME, thermoblocks simply cant produce powerful enough steam to cope effectively with more than one (maybe two) standards drinks at a time.

    While a dual thermoblock machine might enable the user to pull shots and steam simultaneously - is the steam production powerful enough to keep up???
    If steam production is what you fear the most, then fear no more. The Sunbeam EM6900 will steam till the cows come home with enough force to microfoam all your lattes.

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    Re: Thermoblock versus Boiler

    Quote Originally Posted by wattgn link=1118073813/0#10 date=1120966090
    Really very basic so measuring temperature variation during a shot should give a very objective measure of the machines ability to produce good espresso.
    I see a lot of posts that confidently predict a theoretical ability of a thermoblock to deliver temp stability. *Sorry, I just dont see how.

    A thermoblock is an array of honeycombed channels that water runs through, picks up heat from, and comes out the other end. *By definition (and plain physics) the thermoblock is going to cool as water runs through it. *The first water that hits the coffee will be hotter than at the end of the shot.

    Compare this to a boiler machine that dispenses water that is pre-heated to brewing temperature. *No cooling issue here, but it depends a little on boiler temp stability.

    Now compare to a HX machine. *Conceptually this IS a little closer to thermoblock in that cold water runs through a channel and is heated. *In this case, though, the heat exchange is from a large boiler that has the ability to recover the temperature loss from cold water by using its excess heat reserves. *The pipe that runs through the boiler is heated by boiler water at the same time as the espresso water cools it. Because the same highly conductive agent (water) is doing both the heating and cooling, you can achieve equilibrium.

    In order for a thermoblock to match either of the above methods, it would need to be enormous and very heavy. *Even then I doubt that most durable metals could conduct heat quickly and accurately enough to recover temperature lost between the start and end of an espresso shot. *Sunbeams new machine boasts stainless steel, which is better than aluminium for durability, but its a poorer heat conducter. *The rest of the industry uses aluminium thermoblocks for heat conduction reasons, at the expense of durability. *Either way you lose. I can see why Sunbeams design team opted for durability in their new high end machine - it fits the rest of the image marketing for that model - but dont take it hook line and sinker, people!

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    Re: Thermoblock versus Boiler

    Quote Originally Posted by ShortBlack link=1118073813/0#12 date=1121159849
    *By definition (and plain physics) the thermoblock is going to cool as water runs through it. *The first water that hits the coffee will be hotter than at the end of the shot.
    Hi ShortBlack,

    So, then how do you explain that I can open the steam up full power and it just never slows or looses power at all. *It just keeps on frothing as long as I like. *A thermoblock is creating the steam as well as a thermoblock heats the water for the coffee. *Maybe, there is more to physics than we know?

    I dont know myself. *But I am not a physics graduate. *
    But it works on this machine.
    To be fair, it never worked on my other TB machines I ever tried, though.

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    Re: Thermoblock versus Boiler

    Shortblack:

    I dont think it will deliver the same temperature stability either.

    Mind you as Monti says, the proof is in the tasting. It may be if the temperature stability is reasonable then it may be difficult for most people to taste the difference.

    I dont think though that there is any evidence yet that it will come close to the stability of lets say more traditional technology.

    Still if you look at the machine, it has a lot to offer and it looks set to kill off top end consumer machines like the Gaggia which from what Sparky has determined might even be less stable than a good thermoblock machine like the Sunbeam.

    Grant


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    Re: Thermoblock versus Boiler

    Just remember everyone, that you cannot compare the new Sunbeam EM6900 to any other TB machine. It is head and shoulders above them all, IMO. If you are comparing it as if it was a normal TB machine you are going to be way out with your assumptions.

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    Re: Thermoblock versus Boiler

    Quote Originally Posted by Monti link=1118073813/0#13 date=1121160501
    So, then how do you explain that I can open the steam up full power and it just never slows or looses power at all. *It just keeps on frothing as long as I like. *A thermoblock is creating the steam as well as a thermoblock heats the water for the coffee.
    Monti, when it comes to the separate steam thermoblock I would guess that Sunbeam got it right. For that particular job all you need is a temp over 100C. How far over doesnt matter. If you have a block of metal and a big enough electrical element you can steam all night! Just ask anyone who uses a steam iron (even a Sunbeam one ;D) .

    But the espresso shot is another matter. For espresso you need stable temperature, not a minimum temperature. And that is where thermoblocks inevitably fall down. Please dont get me wrong - the Sunbeam may deliver a decent AVERAGE temperature through a coffee shot, but proper extraction depends on consistency to minimise the burnt and sour tastes that come from temps that are respectively too high and too low.

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    Re: Thermoblock versus Boiler

    Quote Originally Posted by ShortBlack link=1118073813/15#16 date=1121161410

    Monti, when it comes to the separate steam thermoblock I would guess that Sunbeam got it right. *For that particular job all you need is a temp over 100C. *How far over doesnt matter. *If you have a block of metal and a big enough electrical element you can steam all night! *Just ask anyone who uses a steam iron (even a Sunbeam one *;D) .

    But the espresso shot is another matter. *For espresso you need stable temperature, not a minimum temperature. *And that is where thermoblocks inevitably fall down. *Please dont get me wrong - the Sunbeam may deliver a decent AVERAGE temperature through a coffee shot, but proper extraction depends on consistency to minimise the burnt and sour tastes that come from temps that are respectively too high and too low.
    Except, if you have a certain size of block of metal big enough and you know how much it will heat the water if it passes through it at a certain speed and volume then you have the temp controlled. *Dont think of it as the heating element heating the water inside of it and when it starts pumping itll have new cold water passing through it. *Rather, IMO, it has no hot water inside and the same temp water passes thorough it at constant speed and volume, so the temp of evey drop should be the same from start to finish. *

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    Re: Thermoblock versus Boiler

    Quote Originally Posted by Monti link=1118073813/15#17 date=1121162268
    Rather, IMO, it has no hot water inside and the same temp water passes thorough it at constant speed and volume, so the temp of evey drop should be the same from start to finish. *
    Monti, any thermoblock would be empty at the start of a shot. Thats not the issue. Regardless of the speed and volume, the start of the shot will be hotter than the finish because the water draws heat from the metal as it passes through. The last 30 mls will have less heat to draw from the metal because it has been cooled by the first 30, and the metal wont have had the time to recover the right temperature.

    Ive pretty much said all I can to describe a thermoblock to you! Having said that, if your Sunbeam makes you a good cup of coffee then all is well and you should enjoy your purchase.

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    Re: Thermoblock versus Boiler

    wouldnt the elements be on during the pour thus canceling out to a certain extent the temp dorp caused by the cool water comming in?

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    Re: Thermoblock versus Boiler

    Rich:

    It is difficult to say what is happening in the thermoblock.

    It is a real balancing act dependent on flow rate, heating rate of thermoblock, thermal mass of the thermoblock, reaction time of the thermocouple to changing temperature and the logic it uses to control temperature.

    I still think it is an incredibly difficult tightrope to walk. In an ideal world you would have instant energy and instant response to changes in temperature. In reality the logic in the microprocessor will do a lot of prediction based on less than instant response times of the thermocouple to varying flowrates (which it can only estimate from temperature changes), the thermoblock cant transfer heat instantly either so it is all rather approximate.

    The boiler is a sledgehammer approach to this delicate balancing act which works! ie. low tech, brutal, somewhat inefficient but very effective and stable.

    I guess we will see just how clever Sunbeam is over the next few weeks or months as interested techies do their own measurements.

    Grant

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    Re: Thermoblock versus Boiler

    Quote Originally Posted by wattgn link=1118073813/15#20 date=1121175001
    It is a real balancing act dependent on flow rate, heating rate of thermoblock, thermal mass of the thermoblock, reaction time of the thermocouple to changing temperature and the logic it uses to control temperature.
    Grant
    Hi All,

    I dont believe that it is an all that difficult task to overcome... given that the design would have to take into account the variables that effect the outcome and then have a suitable control mechanism to deliver the desired outcome.

    Im sure Sunbeam and many other companies have the where-with-all to successfully achieve such a design and its implementation. The actual physics involved is minuscule in comparison to that of many other appliances, its the economies of scale that will determine how far companies like Sunbeam are prepared to go in order to satisfy the wants and desires of hobbyists such as ourselves.

    Cheers,
    Mal.

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    Re: Thermoblock versus Boiler

    Mal:

    Well, I dont agree with you at all on that point.

    Well see though, you could be right but up until this point in time, thermoblocks havent delivered for all the reasons just discussed.

    Microprocessors help for sure to work all this stuff out. At the end of the day though it is old fashioned thermocouples and pumps and heated thermoblocks which have to do the work.

    You could look upon the boiler as just being a very large thermoblock, one where all the balancing and timing issues are ironed out by the thermal mass in the boiler.

    The thermoblock you could look upon as being a very small boiler, which is pretty well what it is.

    I suspect that thermoblock technology may be good enough for the average consumer but Id be very surprised if it matches the performance of a good boiler.

    I was just thinking about the last time we used the commercial machine at Supreme Coffee Machines. One of the things I noticed was the tendency to easily burn coffee. You have to be so careful not to let that group heat up. Tricky. Boiler machines still seem to be the best solution to good temperature control especially with good PID/microprocessor control built in.

    Well soon see.

    Grant

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    Re: Thermoblock versus Boiler

    There is nothing innate to the Thermoblock system that makes it inferior to the Heat Exchanger based system. In point of fact the Thermoblock type system is capable of better control and more effeicient use of energy than the HX type system. *If youre willing to pay the bucks required to build such a system.

    The shortcomings we see in the TB based systems are not with the principles of TB systems but rather in their application.

    Whats that you say? "You can claim thats the case but wheres the proof? Theres not a single TB based system out there with great thermostability!"?

    Perhaps not in the espresso world. In the science world however such systems have been around for decades. *Every high-end piece of lab equipment I have seen made with-in the last 20 years that needs to heat a solution up for testing purposes uses guess what, thats right, a Thermoblock type system.

    Most of these systems have a thermo-stability measured in tenths of a degree with some Ive seen being as accurate as +/- 3/100ths of a degree F. with the newer ones probably accurate to a hundreth of a degree or better by now.

    Due to the very nature of their design (assuming of couse that its actually *built to be capable of it) Thermoblocks are in point of fact more thermally stable and more controllable than Heat Exchanger based systems. Both theory and physical application proves it beyond any shadow of a doubt.

    Just because a machine is a Thermoblock does not automatically make it inferior to a Heat Exchanger based system.

    Yes, based on what weve seen in the past for TB based systems in the espresso world it *probably is, but it might not be.

    Eventually someone is going to put the needed engineering into a TB based espresso machine that will give it thermal stability like nothing weve ever seen before in the espresso world, but that lab workers have been seeing every day for decades and take for granted.

    Before we rip on a new Thermoblock based machine lets give it a chance to prove itself. Who knows, perhaps somebody finally got it right.

    Java "First test, *then decide!" phile
    MattyRay likes this.

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    Re: Thermoblock versus Boiler

    Quote Originally Posted by ShortBlack link=1118073813/15#18 date=1121165589
    Monti, any thermoblock would be empty at the start of a shot. *Thats not the issue. *Regardless of the speed and volume, the start of the shot will be hotter than the finish because the water draws heat from the metal as it passes through. *The last 30 mls will have less heat to draw from the metal because it has been cooled by the first 30, and the metal wont have had the time to recover the right temperature.

    Ive pretty much said all I can to describe a thermoblock to you! *Having said that, if your Sunbeam makes you a good cup of coffee then all is well and you should enjoy your purchase.
    I have to disagree with you and also with Wattgn, and agree with Rich and Rae.

    Guys, look at it this way:
    I you send water with a constant speed and volume down a pipe that is heated all the way through, then at the end of it every drop of the water will be the same temperature if the pipe is long enough, regardless you send chilled or room temperature water. If you want to control the temperature at the end of the pipe even with different temperature waters going into the pipe, all you have to do is to make the pipe longer. If the pipe is so long that the water is reaching the required temp by half way up the pipe, then the water just travels on from there, at the same temp, till the end. If the water starts out colder, then it will just travel further up the pipe before it reaches the required temp, and then just travels on the same to the end of the pipe.

    Not so difficult at all and no microprocessors needed with fast adjusting ability. All is needed is constant speed of water (pump), constant volume (diamatre of pipe or tubing) and an appropriate length of pipe or distance for the cold water to travel. They are all easy to achieve with primitive and cheap techology.
    The reason it hasnt been done is because there hasnt been a need for them to build one. People havent been asking for them. There hasnt been much competition for this type of machine, etc.

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    Re: Thermoblock versus Boiler

    Im sure thermoblocks can ultimately work as well as, if not better than boilers. Whether they can do so economically is another question. Lets face it, coffee machines use the simplest technology (large thermal inertia) to achieve their goal. But large thermal inertia has its disadvantages such as inability to respond to change. Using the KISS principle (Keep It Simple Stupid), the boiler machines are the way to go. For exquisite control of water temperature using feedback, boilers would not be the best.

    One point with boilers is that if the cold feed water introduced during a shot mixes efficiently with the boiler water, it will inevitably lower the brew temperature. If it doesnt mix efficiently, then the boiler temp can remain approximately constant provided the cold feed water remains segregated from the water delivered to the group. So its a matter of intelligent design, not just size. It also not just a matter of the thermal inertia of the system, its also and primarily based on the fact that water has poor thermal conductivity and so if it doesnt mix efficiently, it will remain segregated, producing cool spots within the boiler.

    One point with thermoblocks is that they must be hotter than brew temperature to ensure rapid heating of the flowing water. That means the water in the thermoblock at the start of a shot will be hotter than brew temperature. So thermoblock inevitably starts out hot and ends cold. The total temperature variation depends on the design.

    Bare in mind that Quickmill have been building high quality thermoblocks for years. Ive heard that the new Sunbeam TB may be based on the Quickmill design.

    PS I agree mostly with Montis statement above. However, it is more complicated than that as as the water heats up it cools the TB, which must be heated to compensate. As a TB thermostat is only measuring the temperature at one point it will average the heat lost and not be able to compensate accurately. However, with a known flow rate and some electrickery, you could pre-program the heating element to provide optimal heating for the load. Ultimately the Sunbeam is just an electronic HX machine. HX machines work pretty well, but have enough stored energy to heat the 30-60 ml of water required for a shot. The TB just has to apply this energy with the heating element. So if a HX machine works, so can a TB.

    Dont judge the ultimate performance of a TB on the performance of cheap TB machines. Theyre cheap for a reason.

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    Re: Thermoblock versus Boiler

    Sigh. I should have given up by now.

    Monti, lets just simplify things and say that espresso brews at 92C. Youre just assuming that a long pipe heated to 92C will give you water at 92C. But it doesnt work like that.

    Heat exchangers need to be hotter than 92C so that water, travelling at a given volume and rate, will reach 92C. Thermoblocks (being a type of heat exchanger) have to be hotter in the hope that the water will heat to 92 as the metal cools (i.e. "exchanges" its heat with the water). This is why the boiler in commercial HX machines is always at steaming temperature, while the espresso pipe that runs through that boiler outputs water at 92C. If you cant grasp that, you may as well stop reading now.

    Now the perfect thermoblock would be at the right temperature to heat the whole shot to 92C, so that the block and the water would both end up at that exact temperature. But here comes the problem. To do that, the water needs to be sitting still and not moving through (like, for example, in a boiler).

    You also assume that a thermoblock will contain just enough water for the coffee shot and no more. Have you wondered how water is pushed through a thermoblock and into your portafilter? Answer: with a pump. What does the pump use for pressuring the coffee shot through? Answer: more water from the tank.

    Enough said.

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    Re: Thermoblock versus Boiler

    Actually if the HX were at the brew temperature it would take an infinitely long pipe for the water to reach brew temperature, as the rate at which heat flows is proportional to the difference in temperature. Thats why HX machines work over a range of flow rates, not for all flow rates.

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    Re: Thermoblock versus Boiler

    Quote Originally Posted by ShortBlack link=1118073813/15#26 date=1121215722
    Heat exchangers need to be hotter than 92C so that water, travelling at a given volume and rate, will reach 92C. *Thermoblocks (being a type of heat exchanger) have to be hotter in the hope that the water will heat to 92 as the metal cools (i.e. "exchanges" its heat with the water). *This is why the boiler in commercial HX machines is always at steaming temperature, while the espresso pipe that runs through that boiler outputs water at 92C. *If you cant grasp that, you may as well stop reading now.
    Heat exchangers do have to work like that as they heat the water in the heat exchanger which is further away from the group head. How far is a HX in an average machine? It is in the middle of the huge boiler. Is it not? While the TB is righ at the mouth of the portafilter in comparison. It is impossible to place a HX close enough to the group head. You have to forget the notion that TB machines work exactly like HX machines. On the surface they do, but in reality there are a lot of differences. Maybe you cannot grasp that? - just to be rude like you in my expressions. Except that I feel bad about being rude.

    Now the perfect thermoblock would be at the right temperature to heat the whole shot to 92C, so that the block and the water would both end up at that exact temperature. *But here comes the problem. *To do that, the water needs to be sitting still and not moving through (like, for example, in a boiler).
    The water wouldnt have to be still at all. It can be moving and being heated at the same time. Is it not? Is it such a crazy idea?

    You also assume that a thermoblock will contain just enough water for the coffee shot and no more. *Have you wondered how water is pushed through a thermoblock and into your portafilter? Answer: *with a pump. *What does the pump use for pressuring the coffee shot through? *Answer: *more water from the tank.
    You assume, what I assume wrong! I had a laugh
    You havent been reading my post properly. You are bing very rude and derogative now and not keeping to the subject. Please, step back in line and have some manners.

  30. #30
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    Re: Thermoblock versus Boiler

    Quote Originally Posted by ShortBlack link=1118073813/15#18 date=1121165589
    Monti, any thermoblock would be empty at the start of a shot. *Thats not the issue. *Regardless of the speed and volume, the start of the shot will be hotter than the finish because the water draws heat from the metal as it passes through. *The last 30 mls will have less heat to draw from the metal because it has been cooled by the first 30, and the metal wont have had the time to recover the right temperature.
    Are you assuming that a whole lot of cold water hitting a thin little hot pipe? *Because I would suggest that rather it is small amounts of room temperature water hitting a thick and long thermoblock that is at the required temperature. *So, the heating element would not suffer from cooling down and the water could reach the required temperature rather fast. *If the mass of the hot pipe is large enough compared to the mass of the water traveling through it then there is no measurable or substancial loss of heat throughout the process, whether it is 30ml or 60ml going through it. *

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    Re: Thermoblock versus Boiler


    I think Javaphile gave some excellent examples. TB designs can easily do the job.

    Lets just sit back and see how the actual machine performs. It doesnt seem too shabby at the moment. A mate who is wanting to upgrade is waiting for Alan Frews verdict. He says hell go with it if it can hold its temperature to within 2 deg C during a shot. Otherwise hell save some more and go with a HX machine.

  32. #32
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    Re: Thermoblock versus Boiler

    I agree Sparky.
    Cannot wait to see the results.
    Hopefully, itll show how good the new Sunbeam is.
    But as I am sipping my own extraction form said machine, I dont need any tests to tell me how good it is. It is by far the best TB machine out there, and at worst, it has clearly closed the gap between the small boiler and HX machines like the Silvia, etc. If one needs something substancially better then it, one now needs something that costs around 4 times the Sunbeam.

    Arent we lucky to have all these choices?
    Arent we lucky that companies like Sunbeam are striving to make better machines at affordable prices so that more of us can enjoy a good coffee?
    Arent we lucky that we can spend less money on the machine and spend more on buying other accessories like a roaster, grinder, or more beans and so end up with better brew in our cups?
    We are getting very spoilt indeed.
    We have to welcome new products.

    I have personally introduced many people to good coffee by showing them or buying them cheap TB machines and who now are working up to better and better machines. Lots of them will be able afford this new Sunbeam and will reach new heights in their effort to strive for a better brew, and they wont even have to give up conveniences that a Silvio has to go without to keep its price down.

  33. #33
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    Re: Thermoblock versus Boiler

    I give up Monti. I wasnt being rude and Im not duped by people who accuse others of rudeness in order to silence their opinions.

    You obviously love your Sunbeam, and love is blind. Im off to my local coffee shops to tell all the baristas to buy thermoblocks ;)

  34. #34
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    Re: Thermoblock versus Boiler

    Quote Originally Posted by ShortBlack link=1118073813/30#32 date=1121298569
    I give up Monti. *I wasnt being rude and Im not duped by people who accuse others of rudeness in order to silence their opinions.

    You obviously love your Sunbeam, and love is blind. *Im off to my local coffee shops to tell all the baristas to buy thermoblocks *;)
    You were very derogative in your posts towards me, indeed. I am asking you, nicely, to stop doing it.
    I am not about silencing anyones opinions. I welcome all opinions (including yours), but there is a way to do it with manners without bullying people. Get off your high horse and join in the conversation with enthusiasm but with respect to others. I have done nothing to hurt anyones feelings here other than having, maybe, a different oppinion on the machine.

    Cheers ;)

  35. #35
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    Re: Thermoblock versus Boiler

    Monti:

    Yes, phew a bit hot in here!

    It is just a stupid machine. I mean whatever we argue about, we, the members are the forum.

    It is good though really that we have something to argue about.

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    Re: Thermoblock versus Boiler


    Ive been thinking.... tinker mode on.... Id bet that if you got two thermoblocks and joined then together, the temperature stability during a shot would rival that from a HX and at 1/10 the price.

    Add some tight temperature control to the second thermoblock and you could dial in your desired temperature. Only problem would be sourcing a decent group/PF combo... Maybe an old Gaggia group/PF... I might have a check on ebay... ;D

  37. #37
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    Re: Thermoblock versus Boiler

    Monti:

    We could settle the debate about temperature stability over about 30 minutes with a thermocouple dipped in your portafilter.

    The lovely thing about temperature measurements is that it is just so OBJECTIVE. The evidence, whether you like it or not, is incontovertible.

    It is like the old race adage, "when the flag drops, the bullshit stops"

    The Silvia is not a perfect machine and I now have a warts and all understanding of my machine and how it works.

    The Sunbeam is still unexplored but this will change over the next few weeks. If it were to be shown that the temp variation is in the range of just a few degrees over a shot and close to the target temp of about 94C then you would find that this machine would be on Geeks buying lists. If more than this then I would say it will be off the Geeks buying list but may still garner some respect depending. If it is more than say 5 degrees variation then it will be "Sayonara Sunbeam".

    It will all be over quite quickly, one way or another, when it happens.

    Grant

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    Re: Thermoblock versus Boiler

    I think a lot of us geeks live very sheltered lives. I believe most people who buy coffee machines dont know how to operate them and are more interested in a design that fits in with their kitchen decor. How many people would know how many degrees their brew water varies? Before I shoved a thermocouple into a Gaggia, most people assumed that they were temperature stable. Im sure Gaggias sales wont suffer now that the cat is out of the bag. In fact I like the look of my Classic. I think it looks better than the Silvia, even though it doesnt perform to the same high standards. How many people dont think past that point?

    Stock every DJ and Meyers with a $600 machine that steams and brews at the same time. Add to that that it looks good, has lots of nifty features... It will out sell the Gaggia Classic on function and maybe looks. The only thing Gaggia has going for it is its name and reputation, and if youre new to espresso, then it doesnt even have that.

    I believe that Sunbeam employ marketing people to identify a market niche and aim their machine at that level. Im sure theyre not aiming at us coffee geeks, but theyre not far off.

    One last thought. When people upgrade their Silvias to HX machines, its usually because the Silvia cant make milk based drinks fast enough. It looks like the little $600 Sunbeam has that one sown up. Being more than $400 cheaper than the cheapest deal on a new HX machine. Id say they have some market niche. The purported performance doesnt even have to be true, it just has to be propagated by the people selling the machines.

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    Re: Thermoblock versus Boiler

    Quote Originally Posted by wattgn link=1118073813/30#36 date=1121313444
    Monti:

    We could settle the debate about temperature stability over about 30 minutes with a thermocouple dipped in your portafilter.
    I am sure many are already doing the testing out there. We are just going to have to wait, I guess. I do hope that they are doing it properly not like that test on coffeegeek where someone just stuffs a huge styrofoam cup under the showerhead and puts a temperature measuring lead through the side of the cup, with the cup jacked up underneath. He is measuring the temp at a flow speed, volume, distance, pressure., etc, that is irrelevant and doesnt reflect conditions that are present when actually extracting coffee.

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    Re: Thermoblock versus Boiler

    Probably the wrong thread, this should probably be in the other argument about thermoblocks, but what the heck ...

    I saw the sunbeam today, in the flesh. Whats with the plastic inside the portafilter? Other than that, it looked nice ... but I must confess, I saw it after an hour or two playing with a dual-boiler expobar brewtus (one of three in Australia) at Forsyths in Naremburn ... the sunbeam just didnt compare with two boilers, PID, E-61 group head ...

    That said, the brewtus will be $1400 more ...

  41. #41
    Avi
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    Re: Thermoblock versus Boiler

    Perhaps the plastic is the "crema enhancer" disc. Never a good sign :) I cant see why a real espresso machine would need such contrivances.

    Id remove that out of the PF before attempting any real brewing. The sign of real espresso is a rust coloured (reddish-brown) crema, not a golden "crema" that emerges out of an "enhanced" portafilter.

    Just my 2 cents worth.

  42. #42
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    Re: Thermoblock versus Boiler

    OK, we are not jumping into conclusions here, are we?

    The plastic inside the pf is not a crema enhancing device and the creama that emerges from it is golden brown indeed and just the same colour as the one I extract from our comercial machine. *The plastic is simply there to make it easy to clean (and it is soooo easy), and to smooth the flow of the brew out of the pf. *If you look, youll see that there is one hole in the middle and it goes straight down into the exit hole. *The oils from the coffee do not stick to it and it is only a rinse and whipe affair to keep it clean. *

    They used SS, brass where it was needed and used some very good quality plastics where it is needed for ease of maintenence. *At least it wont rust like the Silvia does, I guess. *;)

    Ooooh! *
    <Monti runs and puts his motorcycle helmet on.>

  43. #43
    Avi
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    Re: Thermoblock versus Boiler

    Monti...is this "one hole in the middle" a small hole, a pinhole?

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    Re: Thermoblock versus Boiler

    Nothing like a pin hole. Much larger.
    It seems to be the same size all the way through to the two-pronged outlet down the bottom of the pf. It seems to be around 5-7 millimetres but it is only an estimate.

  45. #45
    Avi
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    Re: Thermoblock versus Boiler

    Monti,

    There is no reason to get either defensive or offended by my posts. I was merely curious. I was only asking the question about crema enhancement because many TB machines have these devices installed, I guess to give the impression that these machines can actually produce real espresso.

    Personally I couldnt really care less. Your crusade is your own, and I hope that you understand that neither I, nor anyone else here is trying to attack you or yr new machine.

    What people are trying to do is determine the truth about this machine. You will have to admit that Sunbeam has a far from stellar record in producing machines for the connoisseur. This is why any claims to the contrary is greeting with scepticism. And it is why many of us would like to see an objective review on this machine, performed by an expert. We will not have to wait long.

    Avi

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    Re: Thermoblock versus Boiler

    Quote Originally Posted by Avi link=1118073813/30#44 date=1121395542
    Monti,

    There is no reason to get either defensive or offended by my posts. *I was merely curious. *I was only asking the question about crema enhancement because many TB machines have these devices installed, I guess to give the impression that these machines can actually produce real espresso.
    Defensive? *What do you mean? *I just gave you the answer to your question. *If I was, I am sorry, *didnt mean it, but what are you refering to if you dont mind me asking?
    I dont blame you if you are a sceptic at all. *After all, there hasnt been a TB machine like the EM6900 before. *I have no problems with your questions. *Keep them coming. *Ill do my best to give you the answers, and my oppinions too.

    Personally I couldnt really care less. *Your crusade is your own, and I hope that you understand that neither I, nor anyone else here is trying to attack you or yr new machine.
    *

    What crusade? *I am just happy and amazed that a TB machine can be this good, myself. *That is all. *Sorry, if that is out of line. *

    What people are trying to do is determine the truth about this machine. *You will have to admit that Sunbeam has a far from stellar record in producing machines for the connoisseur. *This is why any claims to the contrary is greeting with scepticism. *And it is why many of us would like to see an objective review on this machine, performed by an expert. *We will not have to wait long.
    I agree with you all the way. *I just like to give things a chance and gather the facts before I shoot them down. *So far the only fats I have is that it makes damn good coffee and the steam is more then powerful enough and never runs out. *It also looks damn good. *8)

  47. #47
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    Re: Thermoblock versus Boiler

    Hi All,

    I think that without solid data resulting from an independent and respected reviewer/tester pushing the EM6900 though its paces, is just causing this thread to disappear into an ever decreasing spiral of argument, counter-argument and frustration on many fronts. We will all have to wait until such data is available before coming to any conclusions about the pros and cons of said machine before venturing further conjecture and argument.

    All that matters at the moment is that Monti is more than satisfied with all facets of the EM6900s performance, build quality and quality of the shots produced and that is surely the most important thing for now?

    How about we all wait until the data is published, eh? :)

    Cheers,
    Mal.

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    Re: Thermoblock versus Boiler

    I need morrree measurrrrements Captain otherwise this threads gonna bloooowwww!!!!


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    Re: Thermoblock versus Boiler

    Behmor Brazen - $249 - Free Freight
    I had a laugh



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