E61 Flow Control Kit: geni.us/VgfzTA Rocket Appartamento: geni.us/q5Wz (As an Amazon Associate I earn from qualifying purchases)

i bought a Profitec Pro 700 with flow control about four years ago. I serviced the E61 group head this past weekend. I replaced the flow control top hat with the standard top hat during the service. The standard top hat came with the mashine and was new. I had experimented with the flow control but hadn't really seen a huge benefit. I'm happy if I can dial in and maintain proper flow as the beans change overtime. I hadn't touched the flow control in over three years so I made no sacrificek tin swapping out the flow control. The flow was a little stronger from the new top hat probably because there was some scale in the jet and screen on the flow control one. Just sharing my experience for perspective.

Best explanation of flow and pressure relationship, something no one else seems to understand or explain! Well done. Makes so much sense.

If you were my physics teacher I think I would have actually passed. This explanation was awesome!!!

Physics is either your best friend, or your worst enemy. Great video as always!

You are one of the best at explaining something period. I could listen to you all day, every day!

Great explanation, it seems to me the best fitting method of flow control to an E61. Not a precision instrument but adding a rather charming character to espresso extraction with an E61, just like the E61 itself is not built for precision but for charming character.

Your videos are always intuitive and helpful

Very expressive! Like the simple picture, easy to understanding the priciple:)

As a engineer, I appreciate this level of detail explanation. Thank you!

Just purchased a LUCCA M58 with flow control. I appreciate your detailed explanation.

This was super useful, thank you for this detailed educational video!

This is definitely the best description of how flow control works! Great video. I've attempted to describe it previously to others in a similar way. Let me know if this sounds right. Basically you have control over the flow rate, but not pressure directly. Max pressure is limited by the resistance of the coffee bed and then the OPV or Pumps max pressure setting. The pressure is not easy to precisely control because it either is going up or down, if the flow rate going into the coffee bed is higher than the flow rate coming OUT into the cup then you'll have pressure building, if the flow rate going into the coffee is lower than the flow going OUT to the cup then the pressure will be dropping, and I find the range between the two settings (where you are lowering or raising the pressure) is a very small range (so I think the Lelit Bianca, which I've never personally used, with a more limited range paddle, might actually have an advantage here over most other E61 flow control kits/knobs).

Excellent overview and about the best explanation I’ve seen 👏

Incredibly good. keep iy technical I love the detail we can always google generic advice, but technical advice is always best in a video and I love the detail. Going from high level to detail level back to high-level very good teaching method Thank you.

Really well explained. Thank you!

Great video. With pressure gauge between the flow control and the coffee puck providing some feedback, adding a flow control could really increase my coffee game. Especially when it comes to impacting coffee through the bloom stage of extraction. Thanks!

Excellent summary, I found an article years ago with similar content but there are a lot of less accurate opinions out there. I appreciate that e61 flow control will sometimes allow me to save a shot if my grind is a bit off.

Excellent video! Learned something myself. Would also love to see mention of the OPV valve in the equation. Also as many other comments have pointed out, an exploration on the effect the flow control will have on a heat exchanger machine. I imagine a blooming shot would cause the water to get much hotter

Great video! I would only add that with certain machines (such as the Lelit Mara X, which I own) the original water debit (pump flow rate) with no resistance is really low at around 5ml/s and that limits the potential profiling. Combined with the natural slow ramp that pump also has it makes flow profiling almost worthless at least to me.

Very well done. You made it clear

The best explanation! I was wondering to instal one on my Cinquantotto, now I'm going to instal it. I just like to see, some tips in how to use it. :) Thanks for your content!

absolutely amazing explanation

Good explanation. I love my Coffee Sensor flow control on my Profitec Pro 600.

Would love to see a part 2 video where you lay out how the flow control changes the taste of a couple different beans and roast levels.

So easily broken down, another amazing video! 😊

What a great explanation of flow control! Thanks

Great video! Very well made!

So wild you dropped this video because I was just looking into flow control for my ECM Synchronika over the last few days!

Thank you very much, that helps a lot to understand that this some kind of indirect influence on the pressure flow. I would have loved to see a concrete example of you using it - and what effects can be achieved ;-)

Really great video, can you make another one on different profiles with e61 flow control. And why are you having it with thermometer, and not the pressure gauge?

Very well explained! I will mount mine shortly:-)

Totally agree - coffee nerds creators do not talk about the flow profiling is just a guess especially as no one talks about the coffee has on the profile

Thanks for your explanation about flow control. Wondering what the taste difference between e61 flow control and manual lever flow control uses the same recipe. I think on the manual lever it's a bit difficult to do decline recipe.

As a science nerd, I LOVE your explanation!

As a reactive tool - paired with a feedback-showing pressure gauge - the valve under the flow control knob could be easyer to use with "large range movements" (thinking about Coffee Sensor kit with its multi rotation movements from wide open to complete shut), or with "small range movements" (thinking about the Lelit-like valve with its bulcky paddle which movements are limited by the machine's front panel) ? (Maybe it could be a matter of valve's screw pitch...)

great videos, thx for sharing.

Very interesting thankyou. I have been wondering how best to use grind size and the ability of my leaver machine (a Europicola) to control pressure, preinfusion time and flow rate to get the best coffee. Please, please do a video on that. Thanks Tony

If you study the water debit at different position of the paddle, you can measure how much water flows. Then with feedback of the pressure build up when there is an espresso puck. You know if the grind is coarse or fine if the pressure is not ideal. Even Slayer has a pre brew water valve at lower flow rate. So like Lelit has found a more engage flow - pressure profiling. Thank you.

I have an appartamento too. Would a flow control kid be a good alternative to an OPV Mod to bring the pressure down form 12 to 9 bars?

Thank you!

Set flow rate to around 2.5ml/s, start shot, if you got your grind correct pressure will slowly rise and top out at around 5-7 bar, pressure will then start to slowly drop but your flow rate will remain consistent, stop shot at desired volume and enjoy your Lazyboy. I've been doing this for over a month, I make small adjustments if it looks like I've dialled in a little too fine, just open it up a few mm and it will fix it instantly, overall I never go above 3ml/s now as that appears to be the cutoff for meaningful flow profiling as the group head matches the pump pressure as quickly as at 7ml/s. This has been conformed by a friend with a Profitec 600, I'm running an ECM Classika II. Thanks as always for the thought provoking videos. Oh and yes, 100% worth it.

Great video!! It would be awesome if you could make a video on guidelines for different profiles. WLL made a video that flashed up profile graphs for fresh roasts, dark roasts, lever profile, sweet bump... But it was overly generic and the graphs don't actually translate well at home. You mentioned controlling flow to gently get the puck started, and to react to the puck deteriorating... What does this look like in practice? Thank you again

Great video. is that a digital temperature gauge instead of a pressure gauge on the front of the group head?

So ... does lelit bianka v3 with the programming low flow and an accurate programmable pump pressure gets better results or closer to what you were saying that E61's doesn't do ?

This brother can break it down = This guy can really explain it in a way that I understand

Thanks for the explanation! Been waiting for this video. I’m wondering if you’ve found any fluctuation in temperate with the E61 HX machine? Given that the boiler is pumping out water at steam pressure abs then cooling it as it gets to the group, I’m wondering how adding resistance there might change the temperature mid shot.

what do you think about adding flow control to a Diletta Bello Espresso Machine?

Thanks!

Engineer ring is on so class is in session. Great work! I'd say you could get pretty close to flow profiling with the E61 flow control, a Bluetooth scale, and SEP. But it would be a lot to monitor flow rate, pressure, time, and weight in cup repeatably. Coming from manual levers (and this probably holds with E61 flow control), I definitely preferred declining pressure shots but didn't try to exactly replicate profiles, and shots were generally good with no way to pinpoint how some shots turned out great. With the DE1 I do feel I am pinpointing things to incrementally make each shot better

Thanks for this, just gave a follow. I have a few hypotheses/questions (noobie here so take with grain of salt): I'm making the assumption e61 group machines maintain a constant pressure no matter the resistance at the puck. Is this correct? Seems based on what you're saying that less pressure at the group head due to less flow (this is how I interpreted what you said) would not really be so much of an issue if, in fact, the resistance (grounds) is being reduced as time goes on. Why would you want to maintain pressure at the group head when the resistance is being diminished due to extraction? Is this a common desire? What you're saying is that maintaining pressure at the group head WITH lower flow is more ideal than less pressure less flow? Isn't that impossible as theres a mathematical relationship b/w flow and pressure and in theory they should both be reduced with flow control. I would hypothesize that in order to maintain pressure at the group head you would need to have increasing amounts of flow as the grounds degrade? If my assumptions are correct in that theres a mathematical relationship in place between flow and pressure then controlling the variables independently wouldn't be very valuable b/c to maintain flow at the head you would only need to reduce pressure which is what the flow control device should be theoretically doing (and my understanding is it comes with a gauge). Again, major grain of salt as I'm a noob and also not a physics person. Great content, thanks!

Is that the mechine change the temperature?

Super helpful description, definitely worth a thumbs up! An espresso machine salesman told me that Flow control wasn't a good addition on a Heat Exchange machine as compared to a dual boiler. I am curious if anyone might know what the difference could be if any if both machines had an E61 head. Thanks!

Great job…thnks

I love the general idea, but I would love to be able to see both the brewing temperature as well as the pressure build up. Both is unfortunately not possible with my Appartamento and temperature fluctuates too much from shot to shot that I would take out my the grouphead thermometer. I know you could also do a workaround by using a bluetooth scale and shot profiling app to see how flow rate changes over time, but for me that is too much crazyness. I would rather buy a Linea Mini in a few years and do the needle mod and then have a very nice tactile brewing experience.

Love mine

I think a flow control system should be paired with group head pressure gage to have feed back on what is going on. And It will be more useful for rotary pumps machines since they have higher flow rate and fast ramp up to 9 bar.

Good discussion. The only correct and sensible way to control pressure is at the PUMP. This is not a trivial engineering task. The standard rotary pump buried inside commercial machines is manually adjustable for bypass with a screw, what good is that. The Ulka pumps can be electronically controlled with a dimmer type control why bother with a $30 buzzer pump. Currently today there does not exist any customized pump with a stepper motor bypass valve that can be remotely controlled. Maybe I'll invent one.

Interesting video, got my subbed after watching some other video you did :) However it would be interesting to get a video more in depth as of how to use it correctly because it seems like a waste of money and added layer of complexity that doesn't improve anything other than maybe a placebo effect, when I try to use it on my R58 :/ I have it set with the pressure gauge but I notice how hard it is to lower the pressure once it reaches pump pressure "9 Bars" and that it is super unresponsive and far from being proportional! The only thing I can seem to be able to do is limit the ramp up at the beginning but then like I said, once it goes to 9 bars, if I try to restrict the pressure again, it seems like I almost have to full close it down to 100% to see a change on the gauge, wtf? O_o Thanks for the help!

Thank you. Can this device damage the machine or tire the vibration pump (Appartamento)?

I've also noticed, both with my Coffee Sensor flow control mod kit on my Rocket Machine I had previously and the ECM Flow control on the ECM Synchronika both have a gritty / not so smooth feel to them occasionally, sometimes they're super smooth (usually when the machines cold and it's not even being used). So usage / Feel / Ergonomics wise, it COULD be nicer.

I think there's a bit of a confusion about physics here. The decent is not a bit more 'true' flow or pressure profiler as this needle valve solution. It doesn't bend physics, it just presents itself as it if it did. It is the same reaction based system. There's a max pressure and a max flow rate that are roughly the same (or can be set to be the same) on an e61 and the decent. It doesn't matter if you change the pump pressure or the flow rate, the result will be the exact same as they are 100% correlated to each other. Yes the decent does everything automated, but if you follow a set pressure and/or flow profile on an e61, you will get to the exact same result just manually and undeniably less precisely and with less repetability

just got a new machine. i like trying little things. puck screen scales puck prep, but i am happy with that. but not going down this route.

Thanks for making this- it's never black and white! Btw what is the outro song name?

Thank you for making this! I always wondered why I could change the flow rate visibly without the portafilter but it didn’t seem to translate into a profiling a shot in the same fashion. I thought my flow control valve was defective😂

Minor changes in flow doesn’t affect the puck because it’s resistance to flow. If pressure and flow are into linked, and you can cycle the pump on and off without discharging the pressure, just activate the pump a couple of times infusion.

What about machines like the Bianca does this apply? I know they have some electronics in it

if i turn down the pressure to 9 bar, would it affect my pressure for the wand? Thanks

Does flow control work on HX? I have read that it doesn't but I think the apartamento is a HX machine. Do you just need to leave the flow/valve open until you're actually ready to brew?

Great video, than you!

I think they should be called pressure control, as flow control is a bit of a misnomer. Just got a Profitec Pro 600 with “flow control”. Perfect for use with my home roasted coffee.

My only issue is that its hard to find such a thing here in my country :/ also I'm using a Domobar VBM so I'm not even sure if all flow rate controllers are made for the same thread

this being the case, if we have a pressure gauge placed on the group, then we can see what the pressure is in the "P2" zone (according to the diagram)?

Good Video

Just decided to not use the flow control on my quick mill for once. Beans were well dialed in with an e37s, used a 1:2 ratio, no puck screen. The result was excellent and left me wondering, “why continue fussing with this flow control situation?”

Great explanation. What about the needle valve of the Slayer? Is that a good flow control? Or the Rocket R91 has a better flow control? I am trying to decide which machine should I get. Thanks. And any suggestion is very much appreciated.

Correct me if I am wrong, but you could measure the output, flow, with a bluetooth scale and software as the coffee hits the cup? This might be more accurate than using the gauge on the grouphead?

Excellent explanation, why don't more people and companies just use lever machines 🤔? Even my local coffee shops have variable flow rate machines but they don't really use it while those that have lever machines are forced to control it. The latter end up making way tastier coffees.

Cool video. I really like the illustrations. I do not like the use of "resistance" in these formulas. There is no law for fluids which uses resistance likes this. This looks more like Ohm's Law. The flow of water through a coffee puck would probably more closely follow Darcy's Law for fluid through porous medium. Darcy's law does however still specify flow rate propertional to pressure difference. You could justify calling it a "resistance" if you very specifically said it was a simplification of the real phenomena.

Is the kit a one-size-fits-all for any E61 grouphead? would it work for any rocket appartamentto?

I really like my E61 with flow control. I don’t have any other machine to compare it to, but using different profiles definitely improves the taste compared to a flat profile. For me, the draw for an E61 machine is entry cost.

Hmm you image forgets the thermal symphonics. There is flow circulating through the group head independent of the water path to the shower. Yes the water path to shower is a take off of the thermal path. Second the lever machine information is dependant on whether you have heat exchangers for the lever groups or no heat exchanger with water coming directly from steam boiler. When you lower either lever you only get the pressure that is from either type. You have no control as there is no restriction. The majority of your pressure is from the springs on the piston pushing down on lever.

I’d like to see you show what the DE1 uses to control flow rate. The same could be said, It could be the same mechanism but further away from the group head. I’d like to see your diagrams of the tech it uses to back your claims.

Maybe I am a simple guy. The Decent machine I am sure is amazing. Being able to to produce amazing shots is probably unparalleled. My issue is with believing anyone, no matter the skill, really understands the relationships of temp to pressure, flow, time of extraction and whatever else the Decent can do. Understanding how to tweak each feature and how they may offset the other settings. Understanding the grinder, temp and timing is enough for me. I can't see how I can knowingly and consistently improve the shot by adding flow control. Maybe if I added it I would be amazed and change my thinking.

Should I worry to install the flow rate knob with Vibration pump machine

It is a good video for me because I just buy this rocket , after see video I will make it 555

hmm you cant change the pressurize p1 p2 because it equalizes, but the flow will change

IMO they make little sense on heat exchangers, as flow rate varies temperature. On a machine with a dedicated brew boiler (be it single or dual) then it makes much more sense.

You guys do know there’s a digital flow profiler for the e61 now? It’s a bit pricey but definitely worth a look.

At 6:45 into the video you mention that with an E61 Flow Control Device, you don't have control of the flow at all times. This sounds a bit misleading when comparing it to the Decent. Granted I don't have a Decent. With the E61 grouphead, as the puck provides resistance to the water flow,, the water can either make it's way through the puck, or be backed up where it will start filling the water passage area between the flow control device and the puck. In cases of total choking of the machine, the water will end up pushing the air out of the OPV valve, along with some water to relieve the built up pressure. I don't see how this functions any differently than a Decent or any other flow control machine like the Heylo or Mina, which also don't use the E61 grouphead.

Especially with a vibratory pump, why can't you achieve the same result by duty-cycling the pump? Give it a few short bursts at the beginning, not allowing full pressure to build (pre-infusion), then turn in on full-time, and then when the flow starts increasing because of puck extraction, interrupt the pump momentarily a few times to moderate the pressure above the puck.

Espresso extraction flow rate 1.5ml-2ml/s is only achievable on Decent, most of machines will accelerate after 15 seconds or so, results in gusher flow, before your video, I had this question for long time that whether E61 pressure reading on the group head is real puck pressure reading or it was created by the value that controls the flow, the resistance from this value causes pressure and that's the reading we see on the gauge.

The apartamento is a HX how flow controll works in that system

I got one recently and I removed it a few days after the installation. The needle is too thick, and the hole of the gicleur is so big, even bigger than the original one built in the machine, this makes the water control part became meaningless.

I still don't know why anyone would need a tap at the grouphead like this device. You can control flow by controlling pump pressure, or by grind settings. Typically we want peak pressure at 9 bars so you would control flow by grind settings. Typically you want a 50 second shot to produce 60ml so dial your grind settings based on that goal. Where then, does a grouphead tap fit into this work flow?

So your technical breakdown of what the flow control knob does is great, but some of the statements you made are a little off. You said that unlike a decent its not a direct flow control, this is incorrect. It is a direct method of controlling flow, it just won't ever alter pump pressure to compensate for puck resistance.

thanks, now I know I don't need this feature

so lets say the coffee machine has a fixed 9 bar pressure always....when you use this flow control you will still have 9 bar pressure but just slow down the water flow ?

Honestly at this point why not just use a lever machine if you want to control the flow so much?

You convinced me to save my money for a Decent.