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Thread: Temperature sensor - E61 HX or SBDU Group Head Thermometer from TTP Coffee Sensor®

  1. #1
    Site Sponsor CoffeeSensor's Avatar
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    Temperature sensor - E61 HX or SBDU Group Head Thermometer from TTP Coffee Sensor®

    Gene Cafe Coffee Roaster $850 - Free Beans Free Freight
    Hi guys !
    If you have any questions about our product, i will gladly help. I'm Tudor. Me and my family are the ones that manufacture the sensor in Romania, EU.
    Since we started the production, we sold hundreds of units worldwide and keep getting orders.
    We already had some customers from AU + NZ also. Maybe they can post here their impressions and feedback.
    Even if it's not so good, because these ones always can and will improve the experience with Coffee Sensor and also the product itself in my opinion.

    So, for any type of questions and even suggestions on how to improve the product, please write here.
    Thanks !
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  2. #2
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    A double up of the other post as I didn't see this one...

    "So anyone used the Coffee Sensor? Interested in a group buy? (3 needed for free shipping). I'm willing to give it a go, and give me a bit more insight into what is happening at the brew head. Works about $80-ishAUD each, delivered. "

    My only suggestion is based on the website, to have someone who is a proficient English speaker go over it. (some of the words you use, are correct, but not really the right ones). Let me know if you want some help!!

    Before

    The most common question about our coffee sensor is what can it do for you? Well, Coffee Sensor offers valuable and instant information during the entire brewing process of the coffee puck.

    First off, our sensor tells you if your machine is ready to go before your first coffee of the day, by indicating E61 group head idle temperature. After this, you will know how to correctly adjust the cooling flush (by name, a HX coffee machine special cooling process), by knowing the perfect moment of finish and start of the coffee extraction. During brewing, it will show you the exact temperature level throughout the entire extraction. Here, most of our customers finally know if their machine is stable or not or if the pressurestat is set up way to low or way to high. In one case, our customer, when trying to set up the machine and adjust the pressurestat, found out that it's actually broken and the machine was sent off for repairs, being in warranty period.

    In the end, we can say that with the help of our product, you will see the HX or SBDU machine with completely new
    After

    The most common question about our coffee sensor is what can it do for you? In a nutshell, the Coffee Sensor offers the user instant feedback during the entire brewing process, providing valuable information and eliminating guesswork.

    Before you have had your first coffee of the day, the sensor will tell you whether your machine is ready to go from a temperature perspective by displaying the E61 group head idle temperature. This will enable you to accurately utilize the ‘cooling flush’ (a process used by HX coffee machines to ensure optimal temperatures of the brew head). No more maybe, I think it is, kind of, maybe…now you know.

    During brewing, the Coffee Sensor will show you the exact temperature levels throughout the entire extraction. This enables you to gain a better insight as to whether your machine temperatures are stable or not. You may even find out that in fact the pressurestat is set up too low or too high, or even in the case of one customer that the pressurestat is faulty!

    In the end, we can confidently say that with the help of our product, you will see the your HX or SBDU machine with completely new eyes.

  3. #3
    Site Sponsor CoffeeSensor's Avatar
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    Rockford, you're sent from Heaven
    As English is not our first spoken language, it would be great for someone to go over the text parts and give us suggestions.
    If you want it to be you, great.
    Just PM me and send me your request for this help and we'll solve it, trust me.
    I just modified the text that you gave me here.
    Thank you so much !

  4. #4
    Site Sponsor CoffeeSensor's Avatar
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    I would like to add that the start is usually a little bit slow in any country, regarding the orders for the Coffee Sensor.
    Take Romania for instance, first 5 units were sold in a few months and after the feedback started to spread, we sold about 80 units no problem and we are very glad that about any HX machine that is here has a Coffee Sensor installed.
    People don't really know so well our product or company and the use of the sensor.
    Is it so important or not? Does it work a full year and goes after that to the trashcan or...?

    I can offer you a worldwide true feedback about our sensor and the usage part.
    As we sold the sensor in EU, America, Canada, Israel, Arabian Region, AU+NZ and so on, we consider that real feedback is the most important to future customers.
    I started to sell it in Romania. I created one first version and this one, from now, is somehow V2.
    The product is manufactured here. Don't make the mistake considering that it's a Korean sensor resold by us. I still have the original blueprint of the adapter that i and my father in law created
    I did not even know about the korean version, up until i already started to sell the sensor worldwide.
    It all started when i saw a thread on the internet that said something like ,, no more guesswork.". When i started searching the internet and saw that one sensor is 100-170 USD, I wondered what if i could do something affordable and easy to install and use.
    And the answer is yes, it can be done. And i did it.

    Sole use of the sensor will not tell you the exact temp inside the coffee puck, but as a lot of other accessories that we normally use, indicates indirectly if you re in the good / bad zone or not.
    It's the same thing with the boiler pressure gauge. If it's indicating 1, then the temp of the water should be X, if it's 0.8, the temp is...
    The sensor, with the readings that it gives, helps the users understand better the idle and extraction temps. Some people understood that their machine or pressurestat is actually broken. The HX just could no warm up as it should and get to the ideal extraction temperature.
    Some people extracted the coffee at 102 degrees C. Way up. Burned taste in the cup. Some customers had the extractions at 85 degrees. Way low and sour taste.
    The situations are multiple and the sensors always performed well. It helped a lot of customers understand what's up with their machine and how can they improve the taste and machine work process.

    The build of the sensor is solid. One sensor, the oldest, has over an year and goes strong, without any change of the battery. The adapter is uni body, stainless steel, food grade.
    The battery inside the sensor is LR44 type. Changing it is a 2 minute job.
    Installation is straight straightforward, just replacing the hex screw on front of the group head.

    I think we will have our first 3 units order here. Also will send some test sensors for feedback regarding your region.
    Hope my posts help you as much as possible.
    Cheers !
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  5. #5
    Senior Member CafeLotta's Avatar
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    I've become a big fan of grouphead thermometers after having used one now for a few months on a single boiler E61 machine. I think any non-PID E61 machine could benefit from one, especially once the user becomes familiar with the temperature dynamics of their individual machine. It allowed me to identify temperature fluctuation patterns during use and to utilise this information for more precise control of brewing temps. Most important was developing a controlled and repeatable brewing routine.
    Last edited by CafeLotta; 9th October 2018 at 10:10 AM.
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    I bought 3 of them, 2 are spoken for, so if anyone wants the third one, let me know $80.
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  7. #7
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    Quote Originally Posted by Rockford View Post
    I bought 3 of them, 2 are spoken for, so if anyone wants the third one, let me know $80.
    yup i'm keen, i'll send you a pm

  8. #8
    Site Sponsor CoffeeSensor's Avatar
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    Some units already are on their way to Au. I have send them Tuesday.
    Hope you guys will enjoy the sensor and give all the users some feedback.
    Keep in touch !

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    Have received the 3 sent!

    Installed mine in about 5mins, aaaaaand now I've opened a can of worms on myself. I don't know the what/why/how of the readings. So I'll do a bit of a writeup so I can get a better understanding of what is happening throughout the process. It is quite eye opening to say the least the temperature fluctuations throughout the process.
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  10. #10
    Senior Member CafeLotta's Avatar
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    Quote Originally Posted by Rockford View Post
    Installed mine in about 5mins, aaaaaand now I've opened a can of worms on myself. I don't know the what/why/how of the readings.
    It will take a while to learn the patterns during warm-up and brewing. You won't get a meaningful brew temp reading until a couple of seconds after the brew water starts running. You'll see the temp rise and stabilise within a narrower high/low range and with smaller variations in the reading when the machine is at operating temp. Its not a static reading. Eventually you'll see patterns within the variations in temp readings and the speed with which changes occurr.

    If you want a little "light" reading on grouphead thermometer use, start at page 9 of the pdf linked below....

    https://www.chriscoffee.com/v/vspfil...ter_Manual.pdf

    What type of machine are you using?
    Last edited by CafeLotta; 17th October 2018 at 08:45 PM.
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  11. #11
    Senior Member CafeLotta's Avatar
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    Found some interesting videos of grouphead thermometers in use. Much easier to understand what they offer by watching them in action.

    Flush method on a Rocket Giotto Evoluzione Hx machine - https://www.youtube.com/watch?v=xsmGMUdYGQ
    Flushing on Hx machines is a whole different topic - https://www.youtube.com/watch?v=bHSFBM3cWHI

    On Profitec 700 Dual Boiler PID - https://www.youtube.com/watch?v=GFjcEbYc13o
    Having a dedicated brew boiler with PID, the high/low temp variation is a lot less once at operating temp.

    On Expobar Brewtus Dual Boiler PID which pre-heats water pumped into the brew boiler - https://www.youtube.com/watch?v=UrkhkqGcSIs
    Just focus on the grouphead thermometer stability with this machine. Not sure about the reading on the multimeter. I find 1 to 2 degrees lower at the shower screen? At the beginning it seems the E61 grouphead has cooled off a bit or isn't fully warmed-up as there's a fair ramp up in temp before showing actual brew water temp.
    Last edited by CafeLotta; 19th October 2018 at 09:08 AM.

  12. #12
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    Thank you very much CafeLotta for the info.
    We have been very busy this time of year and we are preparing for Black Friday as everybody i guess.

    About the readings, you are very correct.
    But you can get a static reading, but as we i saw from hundreds of hx, only from dual boiler machines. Their stability is just great.
    Once you have resolve the cold nose problem, usually within extraction, you can see a static 90-92 degress on the sensor with no problem.
    The single boiler machines are not so stable and you really do need to learn your own machine patterns in order to better understand the working temps.

    We know a fact that it's tempting to only watch at the LCD readings and think that that is really the temp from inside the puck, but our sensor as others E61 accessories, has to be used in conjunction with other info that you need to learn at any HX machine, like sounds, visual details, taste and very important, the moment in which you start the extraction.

    There are in general two situations in which you can get in:
    1. The water from the boiler is hotter than the group, in a case where the sensor indicates a temp higher than the one from inside the puck
    2. The water from the boiler is colder than the group temp, so you will see lower temp on the sensor but inside the puck you will get a little bit higher temp.

    All this can be solved by a longer warm up and a correct cooling flush / cold nose.

    I really want to see your feedback about our sensor.
    I want to attach proof from one our customer that the sensor is very exact (good calibration) and shows correct readings, by indicating the exact same temp as a thermocouple:
    We had some new customers that wanted to know how exact is our thermometer...

    IMG-20181025-WA0001.jpg

    Cheers !

  13. #13
    Senior Member CafeLotta's Avatar
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    Quote Originally Posted by CoffeeSensor View Post
    I really want to see your feedback about our sensor.
    Thanks for the opportunity to try out one of the CoffeeSensor E61 grouphead thermometers. I'll install it soon and then use it for a couple of weeks to get a good comparison to the one I've been using.
    Last edited by CafeLotta; 26th October 2018 at 08:53 AM.

  14. #14
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    CafeLotta, you have a full inbox, but i will answer here since i think some info is important for all users and future customers:




    Switch the sensor on or off using only your fingernail, not the entire finger, in case you have a big hand
    The sensor has a small protection film on it, when it will be too used, just peel it off.
    If that is not OK, than it could be defective and i can change it with no problem ! The button needs to be pressed with no problems.


    The calibration and accuracy are great for the value.
    It was tested well before going worldwide with this product, because it could have been a disaster for us to launch a product called temp sensor and for it to have way off readings.


    The thermometer can be pulled off the stainless steep adapter. But usually that's not necessary and not recommended.
    The sensors has two main parts, the one that is attached to the adapter and the motherboard and LCD. The second part can be disconnected immediately from the first part and adapter, to change the battery for example.


    It can also be rotated 360 Degrees even. For it to be exactly horizontal when facing the user.
    Just make sure the cables stay in the original position, when you disconnect the sensor.
    If you take the wires from it also, bare in mind that they have a lot of thermal paste on them for maximum contact and good readings.
    If you put them inside again, make sure they have paste on them. If not, please find some thermal paste maybe from the PC world and use it.
    Or check if there is inside and when putting the wires inside, get some paste on them from inside the adapter until you get to final position.


    I would be more than glad to assist you anyway i can during the tests.
    Of course the main thing is to see how the sensor reads comparing to the Eric or any other manufacturer.
    The thing is that the speed is usually the same, since all sensors are manufactured to read between the range -50 - 300 degrees. So the diode and wires are practically the same, as the motherboard also.
    One client called our sensor cheap, regarding the inside look. When we have send the insides of the Eric, he understood that the sensors are the same, just different prices


    If the sensors will read the same, the only thing that separates them is the price and of course, customer service, a thing that a lot of companies lack these days. Especially regarding speed of answering questions / to problems and sending replacements free of charge.
    What i try is to send a cheap but good product worldwide. Think that for one Eric we send 3 sensors and offer free shipping. That's why we sold hundreds worldwide not to mention in Romania, where i think one from 3 HX has the sensor on it.
    Also we keep getting thanks and emails with very good feedback and one more important thing, our product seems to be the one with the best value for money ratio.



    Cheers from Romania !
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  15. #15
    Senior Member CafeLotta's Avatar
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    Quote Originally Posted by CoffeeSensor View Post
    If the sensors will read the same, the only thing that separates them is the price and of course, customer service, a thing that a lot of companies lack these days. Especially regarding speed of answering questions / to problems and sending replacements free of charge.
    Thanks for the additional information and apologies re: full Inbox. It has been cleared. You're quite right, the CoffeeSensor is alot less expensive than Eric's device (expensive US shipping doesn't help) and also less expensive than TheBat device (if it's still available?). Price, quick support with queries and being a CoffeeSnobs site sponsor make your product an attractive alternative. I expect when I get a chance to put the 3 of them side by side (as an end user), their performance in reading grouphead temp will be similar.
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  16. #16
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    Quick review and request for help in understanding…

    I like Empirical Reproducibility insofar as one can produce consistent results with so many variables. (Dosed grinds, coffee distributors, calibrated tampers etc). It may have something to do with working in IT and the realisation that I’ll never be a coffee ‘artist’ knowing how to almost caress the process and make minute adjustments on the fly and go by feel. So the idea of a sensor that could provide me a bit more ‘data’ into the process was always going to catch my attention.

    Ordering was painless and the sensor arrived in about a week all the way from Romania. Installation was seriously a no-brainer, it took me longer to read the instructions than actually do the install. You are provided with all the tools necessary (Allen key and small spanner).

    Do read the instructions!! As it has a couple of safety tips and advice on the install and testing of the sensor and if you get it wrong it could be a painful experience.

    It is small enough not to be in your face, and generally disappears into the general aesthetics/busy nature of an E61 coffee machine. The black backing matches my levers and handles perfectly.

    You don’t have to worry about turning it off as it does itself after a short period of time (5mins?) and comes up to ‘speed’ very quickly when you turn it back on, getting the temperature within about 3secs. It is very responsive and precise to changes in temperature.

    All in all, given the price in comparison to others on the market (less than half the price of others) it has given a real insight into what is happening during the process, and has raised a lot of questions for myself, which I hope to get answered so I can use it to it’s full potential.

    Couple of pics.

    IMG_2671.JPG

    IMG_2672.JPG

    Apologies for the video being blurry, it is from a small P&S camera so a bit dodgy.

    The cooling flush was initiated after the machine had been on for about an hour. You see the temperature go up over 100C (how does that work for water?). Then gradually goes down to about 85C after running for 30secs. Am I supposed to stop the flush once it gets to the ideal temperature? Say 93-95C?


    https://youtu.be/9x_mksPha7Q


    The second Video is the pull, I only took it until the first drops dribbled out, assuming it has reached max temp at that point in the puck, it maintains that temperature for the duration of the pull for about 40secs until I stop. Is this the important one in terms of the end product? It was 95.7C and very steady.


    https://youtu.be/_x0CcYlYMVM

  17. #17
    Senior Member CafeLotta's Avatar
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    Quote Originally Posted by Rockford View Post
    The cooling flush was initiated after the machine had been on for about an hour. You see the temperature go up over 100C (how does that work for water?). Then gradually goes down to about 85C after running for 30secs. Am I supposed to stop the flush once it gets to the ideal temperature? Say 93-95C?

    The second Video is the pull, I only took it until the first drops dribbled out, assuming it has reached max temp at that point in the puck, it maintains that temperature for the duration of the pull for about 40secs until I stop. Is this the important one in terms of the end product? It was 95.7C and very steady.
    It appears that you are using an Hx machine and the high initial temp (100C +) is probably due to the water in the heat exchanger sitting virtually idle for a prolonged period (closed recirculating loop via thermosyphon shown in red in diagram) while exposed to the higher service/steam boiler temps. As you flush through the grouphead, the cooler water from the reservoir pushes out the hotter water in the heat exchanger eventually emerging closer to appropriate brew temp. Flushing this hotter water will raise the E61 grouphead temp to a degree. You probably need to let it stabilise for a few minutes before proceeding to brewing. Working out the correct timing before brewing is the key and where the grouphead thermometer helps.

    Heat Exchanger Generic Diagram.jpg

    The flush and brew method has been discussed at length here - https://www.home-barista.com/tips/ne...ue-t13355.html

    More about HX machines - https://www.home-barista.com/hx-love.html

    In case you're interested here's a real life E61 Hx split to reveal internals - https://www.youtube.com/watch?v=2jn28YTS3OQ
    Shows how a Heat exchanger (in a Hx machine) passes through the Service/Steam boiler to heat water.
    Last edited by CafeLotta; 27th October 2018 at 04:10 PM.
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  18. #18
    Senior Member Jackster's Avatar
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    Nice home barista link!
    Will try the flush and wait.
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  19. #19
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    Hi.
    The grind is too small. The extraction takes to much time.
    The temp is to high on the sensor, i mean the second video, with the pull.

    After one hour warm up, the water will be always above 100 deegres, on single boilers. That if the presurestat is set up correctly.
    I am talking about the moment of the cooling flush start. Very hot water, just as CafeLotta mentioned, comes directly from the heat exchanger, since it just sat idle for a prolonged period.
    The key is to stop the flush just in time to get during the extraction between 90-92 deegres on the sensor, as steady as possible. This is where the HB link will give you the basics of the correct method and ways to test and cool your machine's water.
    I think yours will have to go lower (presurestat setting), even with a correct cooling flush, you will loose much less water and will get to the correct temp, don't worry.

    Keep in touch.
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  20. #20
    Senior Member Lyrebird's Avatar
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    Quote Originally Posted by Rockford View Post
    You see the temperature go up over 100C (how does that work for water?).
    Because the water is still under pressure (see the Antoine equation).
    Last edited by Lyrebird; 28th October 2018 at 02:40 PM.
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    Yep understood, now I've read all of Cafelotta's articles/vidoes, it all makes sense.

    I've eased up on the grind. I will need to research changing the pstat and temperatures.

    From the article it is around 95C as a good starting point, and to make sure I don't fluff about after the cooling flush (45secs). I can't experiment at the moment as I am almost out of beans and the next roasting date is not until Wed so have to be mindful.
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  22. #22
    Senior Member CafeLotta's Avatar
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    Quote Originally Posted by Rockford View Post
    I can't experiment at the moment as I am almost out of beans and the next roasting date is not until Wed so have to be mindful.
    Was that a Behmor on your Christmas list?

    Just wondering whether the machine in your photos is a Bezzera Magica?

  23. #23
    Senior Member CafeLotta's Avatar
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    Hi Tudor, I tried installing the CoffeeSensor on the VBM grouphead today and ran into a clearance issue. Unfortunately the Hex nut part of the fitting doesn't clear the grouphead even with 4 copper washers (see photo below) and it would need even more washers to clear and allow for tightening. (I ran out of washers).

    CoffeeSensor.JPG

    For use on the VBM the CoffeeSensor design may need to be modified - maybe the Hex nut machined thinner similar to Eric's? I think 4 Washers is already too many.
    ***I looked back over some reference material and it appears that Eric had the same issue with Vibiemme (VBM) E61 groupheads. He had to machine the Hex on his fitting thinner to get clearance. I think you would also need to lengthen the round section under the Hex to clear on VBM groupheads with the CoffeeSensor.

    To compare the fitting lengths with the other group thermometers, refer the photo below. TheBat device is on the left, Eric's device in the middle and the CoffeeSensor on the right. I've tried to keep the flat surface at the end of the screw thread on each fitting in line. As a reference, Eric's device with 1 copper washer has a minimal grouphead clearance to the hex nut when tightened.

    Thermometersx3.JPG

    *** P.S. I solved the issue with the on/off button by carefully lifting the protection film off the buttons and re-positioning back over them. Seems to work fine now when turning On/Off.
    Last edited by CafeLotta; 29th October 2018 at 07:29 PM. Reason: ***Information added

  24. #24
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    Quote Originally Posted by CafeLotta View Post
    Was that a Behmor on your Christmas list?

    Just wondering whether the machine in your photos is a Bezzera Magica?
    Gawd, I can't even begin to imagine me roasting my own. Best leave it to Andy. :-) (maybe one day)

    Correct, it is the Magica.
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  25. #25
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    Hi CafeLota. Thx for the info.
    We had very few VBM customers until now. We know about this possible problem. For some time, we have send only one copper washer.
    After some feedback just like yours, we decided to add three more. The feedback was Ok after that, regarding some VBM models. That's why we keep sending the sensors like this, with 4 washers.

    We know about VBM owners and the smaller angle between the grouphead and the zone where the sensors is installed, but until the new lot of sensors will be manufactured, will keep sending more washers to solve the problem.
    Even in the instructions, we mentioned that some machines need more washers.

    The new design will have more flat bumper zone between the grouphead and the hex zone, where customers tighten the sensor with the small wrench.
    Also, the tip will be flattened, not like now, looks like the tip of an arrow.

    About the washers, i can send some towards you, no problem.
    In the metrical system, the washers are 6 x 10 mm. Usually they are found at kitchen and sink appliances.
    Please send me the feedback if you found some washers yourself or i can send them.

    Keep in touch !

  26. #26
    Senior Member CafeLotta's Avatar
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    Quote Originally Posted by CoffeeSensor View Post
    We know about VBM owners and the smaller angle between the grouphead and the zone where the sensors is installed, but until the new lot of sensors will be manufactured, will keep sending more washers to solve the problem.
    Even in the instructions, we mentioned that some machines need more washers.
    With respect, I don't believe washers are the answer here. If you look at the photo with the 3 thermometers, the distance between the bottom of the hex of Eric's thermometer in the middle and the bottom of the hex of the CoffeeSensor on the right is how much length you need to make up. The length of the round section under the hex will give you some idea of how much of a difference there is. Eric's thermometer with 1 washer gives a very small clearance to the grouphead but it is a clearance. You should probably try to get access to a VBM grouphead if possible to see for yourself. When I get a chance I'll get some extra washers so I can give you a measurement of how much extra length I think is required to clear the grouphead. A round spacer bush with a washer each side would be better than multiple washers.

    The one thing I hope people installing these understand is that the hex part of the sensor mount should not be contacting the grouphead like what is shown in my first photo in post #23 above. There should be a clearance gap after tightening otherwise you will be tightening against the grouphead itself.
    Last edited by CafeLotta; 30th October 2018 at 11:01 AM.

  27. #27
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    Washers, as I think I explained, are or will be just a temporary solution. I know the problem and the design will be modified. We have one small lot left before getting the problem fixed. As I said, only for Vbm users, washers could be a solution, I thought 3 are OK from 2 Romanian customers. It seems I was wrong or they did not gave me the real feedback I needed.
    Thanks and please belive that this detail about the design will be solved. And it's just a Vbm problem, not for all models.

    LE: this is how the sensor looks on any other E61 machine with only one copper washer. See how mych distance is between the grouphead and our hex zone.
    But of course, you are right and i know exactly how to permanently solve this issue. Just as you said actually.

    20181030_085545.jpg

    VBM indeed has another angle of the hex hole.
    As i mentioned, the design will be modified, exactly where Cafe mentioned. The distance between the lower hex portion and the straight zone, will be increased. Just like Eric's.
    Glad that maybe people now see that i did not copy Eric's design. I preffered using my own one and improve along.
    Also i found out about The Bat and Vidastech after i launched my design worldwide.

    Thanks and keep in touch !
    Last edited by CoffeeSensor; 30th October 2018 at 08:09 PM.

  28. #28
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    I have a Vidastech E61 thermometer that I purchased from Amazon. It looks identical to your Coffee Sensor. Are they the same product with a different name?

    By the way I am finding it to be very useful. I definitely recommend this type of product to any owner of a HX machine.

  29. #29
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    Hi.
    No, not the same products.
    They are Asian, we are from România, EU.
    We have made our own design and parts. The only thing that look the same is the thermometer.
    Thanks.

  30. #30
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    Hello guys.
    We await you for our 3 day Black Friday with a special price for those who want a cheap and reliable E61 group thermometer on Coffee Sensor - Digital Thermometer & Adapter for E61 Groupheads
    The special price will be available from 16 to 18 Nov.
    In the morning of the 16th of Nov, we will start the campaign, around 9:00 AM, romanian local time (Eastern European Standard Time = GMT+2).
    Thanks and keep in touch !
    Last edited by CoffeeSensor; 13th November 2018 at 07:20 AM.

  31. #31
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    Hi guys.
    We've started the BF campaign.
    We offer 30% off for our customers for 3 days.
    Of course, the discount is from the real sale price, so one sensor is 35 EUR now...
    The new price is already available on our website.
    Thanks and keep in touch !

  32. #32
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    Happen to be in Europe at this time so I ordered 3 to get free shipping.
    If anyone would like 1 pm me. Will sell it at cost ($55) + shipping ($9) or pickup in Sydney (east).
    I'll only be able to ship it out on the 3rd of Dec, so keep that in mind, might take a while to get it.

  33. #33
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    Hi Benny. We received your oder. Will try to ship today or max on Monday.
    Maybe other members will want to try and buy the sensor. So maybe you can help us an them to obtain it.
    Since you are in EU, we can send 3 sensor also with free shipping now on BF.
    Keep in touch !

  34. #34
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    Work in progress something new for a new year...
    Hope to launch the new sensor ASAP

  35. #35
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    Hi,

    What is the updates on the 2019 version? Does it fix the clearance issues with VBM?

  36. #36
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    Hi. I am writing just now on the website chat. I guess that's you?
    Yes the compatibility was solved better with the 2019 model.
    Thanks.

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    I took delivery of one of these today - 2018 model I gather. I can confirm that it fits the (non-PID) Profitec Pro 500 with just the one copper washer plus the OEM teflon washer - not with lot of clearance, but just enough.

    [Aside: I confess that I bought this model by accident. I had been aware of Eric's, and went online to buy it. I purchased the coffee sensor model from a UK online shop thinking that it was Eric's, not being aware of the range of options. I now realise that by buying the Coffee Sensor model instead I just saved a fair bit of money, and got an easier install to boot. But I missed out on the 2019 model.]

    @CafeLotta - since you have three of the group head thermometer options, did you have the opportunity to get a sense of the consistency of their readings?

    @CoffeeSensor - Can you please explain this partial quote from your website?:

    "The 2019 model comes with a ... shorter tip, for even more accurate readings than our previous version."

  38. #38
    Senior Member CafeLotta's Avatar
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    Quote Originally Posted by gunda View Post
    @CafeLotta - since you have three of the group head thermometer options, did you have the opportunity to get a sense of the consistency of their readings
    Hi Gunda. Not quite sure what you mean by consistency of readings? If you mean do they give exactly the same reading with the same thermostat setting then all I can tell you is that they seem to be in the same ballpark. I currently don't have PID. Don't get too hung up on seeing the reading as an absolute but rather as a datum reading to work up or down from based on displayed temp. Let taste be your guide as to the best temp . Bear in mind that all of the thermometers are converted kitchen thermometers that individually retail for $10 - $20. The grouphead thermometer conversion/production is labor intensive hence their final price.

    Quote Originally Posted by gunda View Post
    @CoffeeSensor - Can you please explain this partial quote from your website?:

    "The 2019 model comes with a ... shorter tip, for even more accurate readings than our previous version."
    My interpretation of this is that when installed with a minimum of copper washers, the sensor tip is positioned in the optimum position without causing a restriction in the brew water gallery. From memory I think that the mount body was shortened 5mm for the 2019 CoffeeSensor which reduced the insert depth. This was most relevant for VBM E61 groupheads.



    Refer pdf in post #18 in this thread link for determining correct tip position - https://coffeesnobs.com.au/brewing-e...ermometer.html
    Last edited by CafeLotta; 4 Weeks Ago at 09:56 AM.

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    What did I mean by "consistency"? I guess I meant accuracy in the machine. You can test accuracy out of the machine by comparing it to a thermocouple, and I've done that, but it's not that simple. As you noted in your comparative comments, the Coffee Sensor is laggy in response, whereas the thermocouple I currently have on loan is quite a good one and quick to respond, thus a comparison is tricky. That said, I think it's reasonably accurate once it has caught up with the actual temperature.

    But in the machine may be a different thing. Placement is part of it and I should probably pull it out again and do the paper clip measurement thing. (Yes, I had read that other thread - I've been doing a fair bit of research since getting the thermometer.) There's also the impact of the lagginess for in-machine measurement. The Coffee Sensor reading seems pretty stable during a shot, and that could be a favourable reflection on the stability of my machine, with its thermosyphon restrictor, or it could be just the Coffee Sensor's laggy-ness. It would be interesting to know just how different Eric's is in practice during a shot, if you had a feel for that.

    A related question I'm trying to work out is the relation between the Coffee Sensor reading and the measurement at the puck, in the case of a non-PID Profitec 500 with a thermosyphon restrictor. Is the sensor reading higher or lower? There's a fair bit of analysis on Home Barista in relation to Eric's, but the non-PID versions in the US don't seem to have restrictors, since they seem to need a decent cooling flush whereas mine doesn't. People there debate flush and go vs flush and wait, which have different temperature relativities and I don't think either case is a guide to my case where flushes are not needed. (The PID versions seem to behave quite differently, and I don't think they're a guide either.)

    [Background: Why am I worrying about this? Well, as part of a recent service, I had to have the Sirai p/s replaced. I was told that the Scace indicated that the machine was running a bit hot, so they inserted a smaller diameter restrictor, and said that I might find the shots a bit cooler now. In fact I found the opposite - the shots were hotter, and across a range of beans I was getting a slightly burnt taste. I found that a very long flush solved these problems, at which point I noticed that the new Sirai was cycling over 1.12-1.3 whereas the old Sirai cycled over 1.0-1.3. I've adjusted the p/s down and the coffee is more to my liking. I bought the Coffee Sensor to give me some guidance when I try further adjustments, but I need to know how to interpret its readings. I know it's only a guide, but it would be useful to know how to interpret it. For example, one thing it is suggesting is that a 30 minute warm-up is no longer adequate, if it ever was. I wonder if this has been caused at least in part by the new restrictor.]

  40. #40
    Senior Member CafeLotta's Avatar
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    Quote Originally Posted by gunda View Post
    What did I mean by "consistency"? I guess I meant accuracy in the machine. You can test accuracy out of the machine by comparing it to a thermocouple, and I've done that, but it's not that simple. As you noted in your comparative comments, the Coffee Sensor is laggy in response, whereas the thermocouple I currently have on loan is quite a good one and quick to respond, thus a comparison is tricky. That said, I think it's reasonably accurate once it has caught up with the actual temperature.
    Of the 3 grouphead thermometers I've tried, the CoffeeSensor and TheBat device have a slight lag when compared to Eric's device. As mentioned previously, the quicker response of Eric's due to the exposed probe tip can sometimes be more confusing than helpful. I happily used TheBat device for a few months before changing to Eric's. The lag you speak of isn't that significant, maybe 1 or 2 sec (if that?) at worst.

    Quote Originally Posted by gunda View Post
    The Coffee Sensor reading seems pretty stable during a shot, and that could be a favourable reflection on the stability of my machine, with its thermosyphon restrictor, or it could be just the Coffee Sensor's laggy-ness. It would be interesting to know just how different Eric's is in practice during a shot, if you had a feel for that.
    The stable reading is probably a true reflection of your machine. When changing from TheBat device to Eric's device, there was quite a learning curve to be honest with the rapid and wider range of readings displayed due to momentary temp peaks being picked-up. This was and sometimes still is distracting. For brewing, the important information is found when temp readings stabilise during brewing or changes have smaller increments and become slower. They're not a totally static reading in my machine (Single Boiler) which is thermostat controlled rather than PID. The level of accuracy between the 3 thermometers should be similar, it's just the response time for displaying temp change which differs.

    Quote Originally Posted by gunda View Post
    A related question I'm trying to work out is the relation between the Coffee Sensor reading and the measurement at the puck, in the case of a non-PID Profitec 500 with a thermosyphon restrictor. Is the sensor reading higher or lower? There's a fair bit of analysis on Home Barista in relation to Eric's, but the non-PID versions in the US don't seem to have restrictors, since they seem to need a decent cooling flush whereas mine doesn't. People there debate flush and go vs flush and wait, which have different temperature relativities and I don't think either case is a guide to my case where flushes are not needed. (The PID versions seem to behave quite differently, and I don't think they're a guide either.)
    I've been of the opinion that water out of the shower screen is about 1-2 degrees nom. cooler than the average temp measured by the E61 grouphead thermometer. I think I've read the opposite elsewhere but as best as I could measure with a thermocouple bead/multimeter and without access to a Scace device, I'll go with that. Makes sense to me as I'd imagine some minor heat loss to the shower screen, portafilter etc. At the end of the day, I am of the opinion that temps displayed by the grouphead thermometer are a good point of reference but not an absolute. You'll need a Scace to give you that. Taste in the cup is still the best indicator assuming the machine is working correctly.

    A Heat Exchanger machine has the potential to give brew water temp issues if not set-up correctly. From my understanding of these machines, the thermosyphon system needs to be calibrated properly in the factory or by competent service people to achieve correct water circulation through the E61 grouphead at idle so that the recirculated brew water inside the Heat Exchanger doesn't overheat. If it does, the first flush will also overheat the E61 grouphead further. This is when restrictors are used to control the thermosyphon flow. The restrictor size also needs to accomodate the balance between pumped Brew Water flow at 9 Bar (nom) inside the Heat exchanger against water temp in the Service Boiler controlled by the PressureStat (or PID), to finally deliver brew water at the correct temp. Not an easy task to get right.

    https://coffeesnobs.com.au/brewing-e...-location.html
    The post by TC is ex site sponsor Chris of Talk Coffee so can be read as fact.

    I think the Home Barista website is the best source of info for Hx machine grouphead thermometer use. They also have alot of reference stuff on Hx machine design in general.

    https://www.home-barista.com/hx-love.html
    Last edited by CafeLotta; 3 Weeks Ago at 10:07 AM.
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    Quote Originally Posted by CafeLotta View Post
    I've been of the opinion that water out of the shower screen is about 1-2 degrees nom. cooler than the average temp measured by the E61 grouphead thermometer. I think I've read the opposite elsewhere but as best as I could measure with a thermocouple bead/multimeter and without access to a Scace device, I'll go with that. Makes sense to me as I'd imagine some minor heat loss to the shower screen, portafilter etc. At the end of the day, I am of the opinion that temps displayed by the grouphead thermometer are a good point of reference but not an absolute. You'll need a Scace to give you that. Taste in the cup is still the best indicator assuming the machine is working correctly.
    Thanks for that considered reply. I've also tried to measure temp at the puck using a thermocouple and as you say it ain't easy. Yes, the thermometer is just a guide, but even so, I would dearly love to be able to borrow a Scace basket, even just for a day, just to understand exactly what the group head thermometer is saying and how to interpret it.

    I have read Home Barista extensively on the use of a group head thermometer in my particular HX E61 machine, and as you say you read conflicting information about whether it reads higher or lower than the temperature at the puck. From what I can gather, this is because the (non-PID) version of my machine didn't have a restrictor in the US and so they're all doing cooling flushes, and some are doing flush-and-go and other are doing flush-and-wait, and these two routines result in different relativities between the thermometer and the puck temp. But I can't see that this information is of any use to me, who mostly doesn't need to flush.

    Quote Originally Posted by CafeLotta View Post
    A Heat Exchanger machine has the potential to give brew water temp issues if not set-up correctly. From my understanding of these machines, the thermosyphon system needs to be calibrated properly in the factory or by service people to allow correct water circulation through the E61 grouphead at idle so that recirculated brew water doesn't overheat. If it does, the first flush will also overheat the E61 grouphead further. This is when restrictors are used to control the thermosyphon flow. The restrictor size also needs to accomodate the balance between pumped Brew Water flow at 9 Bar (nom) inside the Heat exchanger against water temp in the Service Boiler controlled by the PressureStat (or PID), to finally deliver brew water at the correct temp. Not an easy task to get right.
    Not it's not an easy task, and yes, it's the taste in the cup that matters. And that's exactly my problem. As I mentioned in the final background of my previous post, I'm researching all this precisely because I had issues in the cup after a well-known and well-regarded site sponsor fitted a new Sirai p/s (which as I mentioned is behaving quite differently to the old one) and re-Scaced the machine. It's a long journey back there and so I'm trying to see how far I can get on my own. I've had some success, as measured by the taste in the cup, by dialing the p/s down.

    The thermometer will be a guide as try and readjust the p/s to deliver the best results in the cup. I have no intention of playing with restrictors, although as I said in that background para, the warm-up time that the thermometer is telling me I need now is getting quite long, at least 45 minutes and perhaps 60. I suspect the smaller restrictor is at least partly responsible. I almost wonder whether I'd be better off without one to get a faster warm-up, even if it means cooling flushes. Yes, I have a wi-fi timer, and that's fine for coffee at scheduled times, or when I'm returning home, but a quick shot on a whim isn't really possible, and has me considering an alternative.

  42. #42
    Senior Member CafeLotta's Avatar
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    Quote Originally Posted by gunda View Post
    And that's exactly my problem. As I mentioned in the final background of my previous post, I'm researching all this precisely because I had issues in the cup after a well-known and well-regarded site sponsor fitted a new Sirai p/s (which as I mentioned is behaving quite differently to the old one) and re-Scaced the machine. It's a long journey back there and so I'm trying to see how far I can get on my own. I've had some success, as measured by the taste in the cup, by dialing the p/s down.
    Have you spoken to the people that did the service regarding the changes you are experiencing? As per the link in my previous post, the art of finding the correct size restrictor is a bit of a dark art.

    I'm no expert on this by any means and am happy to stand corrected but my take on what is happening is this. The smaller restrictor has reduced the thermosyphon flow through the grouphead inhibiting grouphead heat up to the correct temp while idle. The small restrictor would also slow pumped brew water flow through the exchanger which could be overheated if the service boiler temp (controlled by the Pstat) is too high. If you drop the service boiler water temp by lowering the Pstat setting, you should be able to achieve the correct Brew Water temp through the Exchanger. If the restrictor is too small though, you won't get the required idle thermosyphon flow through the E61 grouphead to achieve an optimum temp, increasing grouphead heat-up time. Too low a temp in the grouphead will initially steal temp from the brew water as it passes through. This could be overcome in part through trial and error by doing a few sec flushing bursts prior to brewing to correctly heat the grouphead. The grouphead thermometer will help guide you to the correct Pstat setting. You would need to develop a tight routine to take advantage of such a flushing routine, in effect temp surfing. This balancing act shouldn't be necessary though if the correct size restrictor is installed giving both correct grouphead temp at idle and correct pumped brew water temp through the heat exchanger when brewing.

    If you've paid for a service and aren't happy with the results of the new restrictor, I'd be trying to have a respectful discussion with those people.

    A well set-up Heat Exchanger machine is simple and efficient to use. A badly set-up one not so much.
    Last edited by CafeLotta; 3 Weeks Ago at 11:43 AM.
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    First, a p.s. to my previous post, to keep this thread on-topic. What I probably didn't communicate was that I appreciated your comment that the stable reading is probably a true reflection of my machine. On reflection, I think that's right. I'm sure that there is a bit of second-to-second variation that a more responsive device would show. The lagging of the Coffee Sensor probably serves to average that out. As evidence of this, the indicated temperature on the Coffee Sensor rises to the stable shot reading fairly quickly once a shot starts, and starts to fall fairly promptly after a shot finishes. It takes a second or two of three to get to the new reading, but it starts to respond quickly. The fact that it's rock steady during a shot surely indicates that there isn't much variation.

    Quote Originally Posted by CafeLotta View Post
    Have you spoken to the people that did the service regarding the changes you are experiencing? As per the link in my previous post, the art of finding the correct size restrictor is a bit of a dark art. .... If you've paid for a service and aren't happy with the results of the new restrictor, I'd be trying to have a respectful discussion with those people.
    That's a valid point and one that I'm conscious of. I will probably contact them, but want a bit more experience before I do. I want to fully understand my machine's behaviour. I do want to avoid another eight hour round trip plus wait time, or a week or more without the machine, or both, if at all possible.

    Quote Originally Posted by CafeLotta View Post
    A well set-up Heat Exchanger machine is simple and efficient to use. A badly set-up one not so much.
    I'm not sure I could claim that it's badly set up, insofaras it's not overheating, even if left on for prolonged periods, and seems stable during a shot. But I've read what you've said about the impact of too small a restrictor. I have dropped the p/stat range from 1.12-1.30 when I got the machine back to 1.00-1.20. I don't see any evidence that the grouphead is initially stealing temp from the brew water as a result, as even with the lagging of the Coffee Sensor, the displayed temp quickly jumps a couple of degrees up from the idle temp to the shot temp over 3 or so secs. But I will assess the behaviour of the machine against your analysis as I make further adjustments and consider my options. Thanks.

    (What I don't know is what the warm-up was before the switch. It's possible that it hasn't changed. Perhaps I'm just over the limitations of E61 HX, even with a timer.)

  44. #44
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    If any of you are able to use Andy's RoastMonitor Software, this is easily reconfigured to optimise the ability to record a chart of the Brew Water Temp. by the use of a bead t/c sited on top of a prepared coffee puck just prior to locking in. Been doing it this way for many years and works very well...

    Mal.
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    As I mentioned in the first para of reply #41, I've struggled to do this successfully with a good quality K-type thermocouple. It's why I bought the Coffee Sensor. Of course it's possible that I was doing it better than I realised, if the machine hadn't fully warmed up.

  46. #46
    Senior Member CafeLotta's Avatar
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    Quote Originally Posted by Dimal View Post
    If any of you are able to use Andy's RoastMonitor Software, this is easily reconfigured to optimise the ability to record a chart of the Brew Water Temp. by the use of a bead t/c sited on top of a prepared coffee puck just prior to locking in. Been doing it this way for many years and works very well...

    Mal.
    I found that I need to be careful when locking the bead thermocouple into the portafiler as I've had water run inside the wiring insulation and drip onto the multimeter at the plugs. I need to keep the multimeter above the bead thermocouple and vertical in an attempt to avoid water damage to the multimeter.

    Mal, you might be in a position to shed light on this. I was pondering this morning about the correct location of a thermosyphon restrictor. I'd imagine the correct location is at the thermosyphon outlet of the grouphead so that pumped water flow to the OPV and portafilter remains the same. If a restrictor was put on inlet side then I'd imagine with 9 Bar pressure controlled by the OPV, the flow rate to the portafliter is reduced due to the restrictor which would give totally different brew characteristics to putting the restrictor on the thermosyphon outlet?

    Quote Originally Posted by CafeLotta View Post
    The small restrictor would also slow pumped brew water flow through the exchanger which could be overheated if the service boiler temp (controlled by the Pstat) is too high.
    This is possibly only true if the restrictor is placed on the thermosyphon inlet at the grouphead. Not really sure upon reflection.
    Last edited by CafeLotta; 3 Weeks Ago at 11:02 AM.

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    Hi guys. Wanted to let you know we released the pro version of the sensor and our own version of the Gaggia Shower Screen Holder, made entirely from stainless steel 316 Grade.

    Keep in touch!

  48. #48
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    Quote Originally Posted by CafeLotta View Post
    I was pondering this morning about the correct location of a thermosyphon restrictor. I'd imagine the correct location is at the thermosyphon outlet of the grouphead so that pumped water flow to the OPV and portafilter remains the same. If a restrictor was put on inlet side then I'd imagine with 9 Bar pressure controlled by the OPV, the flow rate to the portafliter is reduced due to the restrictor which would give totally different brew characteristics to putting the restrictor on the thermosyphon outlet?
    Won't make any practical difference.

    The thermosyphon restrictor is typically an orifice plate around 2 - 3mm diameter. Taking the smallest of these values, at 3 ml per second (a highish flow rate for espresso) and 900 kPa (approximately 9 Bar) inlet pressure, the outlet pressure of the orifice plate would be about 898.8 kPa, a pressure drop of ~0.13%.

    The "about" in the above sentence indicates that there are unknowns here, an exact solution requires a couple of coefficients which depend on the geometry of the orifice and the pipe in which it is placed. I have assumed average values for the coefficients in the solution above since the intention is to show that the pressure difference is very small.
    Last edited by Lyrebird; 2 Weeks Ago at 03:55 PM.
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