Would love more videos about flow control and profiling 👍🏼

Thank you for this extremely helpful explanation

Using my ECM Synchronika w/Flow control I now use 10 bar pump output pressure, instead of 9. The reason for the increased pump pressure is that, with the flow control I can dial in the brew pressure where I want it over a larger pressure range. I usually am using 8.0 to about 8.5 bar brew pressure, and tapering down the last 10g of the shot for darker roasts. And Mark, like you say, the lighter roasted higher altitude shots seem better with lower brew pressure and somewhat shorter extraction times as they tend to run sour more easily. With the flow control its easy to do - just run the flow to put the brew pressure & timing where you want it. The ECM is really fantastic in all regards, and WLL has been outstanding in every way. Great video Mark - thanks for offering such valuable insight here.

Great explanation, thanks for great video.

Thanks for a great video

Thanks! As I know ECM Classika doesn't allow to make pre-infusion. If the flow control will be installed, pre-infusion will be work in this case?

Super job Marc - thank you! This clears up a lot of my misperceptions about the topic. I wish I lived close enough to attend some workshops at WLL - if you offer them that is.

Thank you!!!

Checking my older Gaggia Classic with your portafilter with gauge mine is on the high side, but did not want to make any adjustments without your recommendations Thanks

Thank you. I'm searching for more info how to setup valve on my Ascaso Dream PID. Pretty often I see pretty high pressure, however it looks like 10 Bars on internal gauge is pretty much ok. As on the head there will be less.

Another great video. I like that you show static vs dynamic pressure. I was wondering if I have a machine with a fixed 15 bar static pressure and no flow control. Would it be possible to get 9 bar dynamic pressure in a reasonable shot duration (20-30sec) by changing the grind size and tamp?

Awesome video, wish I knew that before I was increasing pressure. I did increase to 12 bars and when pulling a shot I could never get to 9 bars in 20-30 sec no matter what I did with the grind size. machine now in yearly maintenance will try to go back to 10 bars in static pressure, thanks Marc

Damn this really good info especially in cheap machine with that pressure gauge. I always wonder why my espresso always thin not thick when bar in 9-10 but turn thick and nice in near 11 bar. Thank you for this info

Hi Marc, I am really interested in this topic. Unfortunately I have an entry-level what you would call an appliance, the Breville Infuser. I've had it for 7 years now and its been overhauled once in October 2019. I cannot externally adjust the brew pressure (or water temperature) so I try controlling pressure and yield by grind size and by programming the volume or manually controlling the pre-infusion and volume using the program and shot buttons. I've had some moderate success controlling yield within exceptable extraction time but have come close to choking the appliance and have indeed occasionally choked it. It might be a good time to tell you that I also have an entry-level grinder, the Breville Smart Grinder Pro which I leave the upper burr on default setting 6 unless grinding for French press when I move upper burr to 9 or 10 which is neither here or there for this discussion. Anyway back to espresso pressure and ratio. I feel like no matter what I do, and I always use good fresh beans sometimes dark which I prefer but sometimes medium dark and rarely light unless it's pourover or press, that I always get a mostly bitter and acidic doppio even when I pull according to Breville's recommended instructions getting a 2 oz (60ml) shot from 17-18 gram dose in a 25-35 second extraction time including pre-infusion 17-25 from 1st drop. I do however, contribute some of the taste to my palate limitations. I sincerely believe I'm one of the people who is incapable of discerning the difference between bitter and sour. All coffee taste bitter to me no matter the blend or brew method which is why I always add some sweetener to my Americano or long black. A shot, press or pourover even taste bitter at a coffee shop mad by trained experienced baristas. The only exception is when I make or buy a chocolate milk based coffee which typically already have some sweetener added. Again, I digress, sorry. So do you have any suggestions for me other than my buying new equipment which I am considering a Lelit Victoria and pairing a Niche Zero neither of which WLL sells. So, your thoughts?

Thanks for a cool video. I'm pretty new to this. Bought an old espresso maker w/pressure gauge, and from what I can see, I always get about 9 bars of pressure, even without the portafilter applied. Is that normal ? Seems unaffected of portafilter mounted or not. With or without coffee. Also, how long time in seconds should a normal espresso shot extraction time be ?

That Static vs Dynamic demo is pretty cool. I had set my vibration pump opv gauge to 9 bar which was factory set to 10. I guess I should set it back to 10 because the pressure at the head will naturally be lower. I'm sure that is having an affect on my shot... ;-)

Thanks again Marc! Three questions. I have a Bezzera Matrix and when I turn down the pump pressure below 8bar I get dramatically less flow volume from the group, so little I can barely rinse the basket after knocking the puck lol. Is that normal? Also what should input waterline pressure be? My machine always shows about 5 bar when not running. Also will you sell the group head pressure gauge or just the flow control complete kits. Thanks!

Nice video! Thanks for the useful information. I have a question, I recently bought a Lelit and when I make an espresso, the pressure gauge indicates 9 bars but as time goes by, it drops to 8.9, 8.8, is it normal not to have 9 bars fixed through the extraction? Will this affect the flavor noticeably? I don't know if it's worth modifying the bars because it doesn't have 9 fixed bars, since disassembling it is a bit difficult..

Like to see a review on the ECM Classika with flow control.

So for light single origin espresso and a finely grinded shot, what brew pressure would you recommend? I have an ECM synchrinika from Whole Latte Love that has flow control but I haven't adjusted the default brew pressure of the machine at all yet.

Great video. On german coffee forums, there is still the myth flying around, vibe pumps need 11-12bar on the gauge to reach about 9 bars on the group. Sure not every machine is made equal and lesser machines may lose more pressure thx to cheap (expanding) waterlines. For most vibe pump driven E61 machines though the pressure diff between gauge(which is directly connected to the expansion-valve via a capillary pipe) and grouphead is bellow 1 bar.

My new ECM Classika shows 9 bar static, and then drops to 4 bar when pulling a shot (18g for 30 sec). I installed the blind basket, and it with that resistance, the machine gauge showed 10 bar. Could it be that my grind needs to be finer and tamped with more pressure to create the needed resistance? Thank you Marc, your videos are great!

To get 9 bars are the group head on a synchornika (rotary pump), I should adjust machine pressure to 9? or 10

What is the issue with my new vbm lollo water is coming out of grouphead 1 solenoid valve while extracting a shot, typically it happens only after a shot right. What could be the problemB

My machine lelit has a rotary pump. With an blind basket I get 12bars of pressure. On extraction I get 11/12 bars for a 28 sec shot. I think I should definitely lower the pressure right?

Hello and thank you for this very useful video. You advise 9 bars for the extraction pressure at the group. I have a Rocket Appartamento (so E61 Hx) since April 2018. I pull my shots with 11g in a single basket EMS or 18g when it's the double basket (IMS). The coffees are rather of medium to dark roast (not very dark but rather dark anyway). I usually draw in 30 seconds. So here's the question: what pressure would you recommend for me in the boiler? (it is currently set at 1.1 bar). Thanks for your help.

Hi Marc! I got the bezzera bz10 recently and the pressure with blind basket is fixed at 12 bar. I actually opened up the case and changed it around 9.8bars(with blind basket) so machine shows me around 9 - 9.4 bars when i brew (but it's not dynamic gauge as you said in video right! So it may be 8 bars?! Who knows) Now. i saw many discussions in websites about vibration pump machines some say 12, 11, 10 even 13 bars = 9bars at the brewing which annoyed me alot also i saw luca (idk if i said it right name) in the bezzera factory claimed 11bars is the way to go for 9 bars so they used to set their vib pump machines at 11 bars(this video were uploaded about 8 years ago tho but now they set it at 12bars) And now I saw your video and you suggest to put 10bars for 9 bar at brew.. I'm confused and sad... I'm just not happy even my shots taste good because i may feel 9.5bars on the machine were not actual 9 bars at extraction.... So i think you got my sight.. Please tell me what's the exact pressure is actual 9bars at brewing on Bezzera bz10.This would be great Marc

Very interesting and well done. The machines you employ, however, are way out of my (and most viewers) price range. I want to calibrate the brew pressure on my Rancilio Silvia. I need to know how to set up (perhaps build from parts) a proper gauge, since the Silvia doesn't have one.

In Italy I loved the espresso makers with the little illy cups. I dont want to use cups here in the states so how can I duplicate that delicious flavor with a reasonably priced espresso $90-140 machine and grinding fresh and fine Kirkland espresso beans? Which machine? Thanks you so much

Hi Mark, I currently own the ECM Casa V and I began noticing that no matter how fine or perfect my grind size is, it will only read 9bar on the gauge. Can you explain why that is? (I used to own the breville barrista express where the pressure gauge seemed much more interactive).

Hello there! I am using Lelit Anna 2 and i adjusted the pressure to 9 bars. However, extraction is fluctuating between 8-9 bars and then tends to stick around 8 bars when i reached 2:1 ratio in tje 25-30 sec time frame. However, does that mean the pressure in the gasket was around 7-8bars? Should i readjust to 10 bars as it was mentionned that vibration pump should be set up to 10 bars so the gasket would be at 9 bars?

Hi Marc, for Rocket Appartamento pressure adjustment, i’m using e61 group head gauge , in this case it should dial at 9 bars ? Or 10 bars? What I have understood that 10 bars only for on machine gauge not group head gauge?

Thank you, Marc. We'd be all bumping around in the dark without your guidance.

Nowhere can I find a video or any other manual on how to adjust the pressure on Bellezza Valentina v2? Thanks for any help!

This must be the single best video regarding how to adjust an OPV, as usual from the WLL guys (sorry I don't know the name of the guy in the video). As mentioned, my espresso's manual (Ascaso Dream PID) doesn't mention a damn thing regarding how to adjust the OPV and, ironically, one of their selling points in its website is the externally-adjustable OPV... Even the local distribuitor of Ascaso in Argentina wasn't helpful as he told me, when I asked about adjusting the OPV with a blind filter, that wasn't the way to adjust it... Anyway, thanks for this!

For the safety of the machine, do you suggest adjusting the pressure while the pump is running or adjusting while the pump is off and then checking?

hello Mark Recently bought a ECM Syncronika with flow control. Why can i not get any dynamic pressure but i have 9.5 bar static pressure.

Can the Gaggia Classic be adjusted if you have a pressure gage on portafilter?

Good morning. Bought an ECM Synchronika(using water reservoir) with flow control and my pre infusion is very short, indeed when I leave flow control valve fully open and make a shot, pre infusion last barely 1-2s? Looking at your video, pressure goes up wayyy slower. I think something is wrong on my end. I use 18g in a double basket and get 2oz in around 23s. Do you know what causes this and how to slow down pre infusion other than having to play with flow control valve? Thanks for your help.

Hi - I have a Profitec Pro500 PID - would lower pump pressure negatively impact on the steaming performance?

Why do entry level semi automatic machines come with 15 bar pressure like oscar 2 and appartmento ?

You are measuring total pressure in both cases. When you deadhead the pump your dynamic pressure is 0. When you have flow, dynamic pressure is more than 0, but is a portion of what you see on your gage reading. You have to calculate dynamic pressure. Your total pressure is different when you flow through the coffee cause that’s the working point of your pump,which is determined by the flow that you output through the restriction you have created with the coffee

Also, I have a Ceado E37S and it says to adjust grind setting while motor is operating. Is that mandatory ? I see you changed grind setting without the motor running. Thank you

What’s the brewtus vib pump set from factory not shore wether to turn mine down when I pull shots gauge around 12 bars

Hi, I got a new machine with vibration pump and did a pressure test with a blind disc, the brew pressure gauge shows a max reading of 9.5 bar, is this too low? In your video you said it should reach 10 bar. Do I need to have it adjusted? Thanks.

If my machine gauge reads 9 bar but my groups gauge reads 10, is my grind too fine?? If I grind any more coarse, shots fly through in under 17 seconds (sometimes only 12) and the result is a really sour shot.

Hi marc my question is i own a ecm synchronika, that when i have no group handle in and run pump i get 9 bar on machine guage. Dont understand how there is 9 bar with no restriction?? With blind filter basket i get 10 bar at guage. Too high? Also i recently plumbed machine in and set line pressure to 2 bar. My guage on machine now obviously shows 2 bar of pressure always, does this 2 bar of pressure affect end brew pressure? Do i need to adjust pump pressure now? Thankyou

Hi there! I have an issue with my coffee machine. when I press the button for the extraction just to rinse the coffee machine and let the water flow, my pressure gauge goes from 8bar to 12bar even if the group head is not inserted and the machine is not actually extracting coffee, and water flow is very slow. when I try to extract the coffee, it takes around 7/8 seconds before the extraction start and the coffee doesn't even have much crema on top. I tried adjusting the grinder but the result is basically the same. is it normal for the pressure gauge to act this way? thanks

Hi Mark. I would like to know how come whole latte love doesn't sell the Melitta caffeo barista TS smart, Melitta caffeo barista TS, etc or any of the Melitta line. Through my research the TS and the TS smart was well received and highly recommended and compared to features, coffee quality, etc are very comparable to the Gaggia or Jura line with a very respectable price point. Also the Melitta line has been around for about 5 yrs or more

Question. If one lives in Denver. Mile high does pressure change?

Hello my friends , I have bezzera10 and i dont know the place for adjust the pressure, would you tell me ?

This tells me of course that Gaggia only includes the way-above-10 bar OPV (12.5, I think?) on the Classic Pro to make the pressurized basket work. Luckily, that's a simple spring swap that (if you don't mind voiding your warranty) takes about 10 minutes.

Does the Guage suppose to move everytime u use?

How do you know that gauge is reading correctly? Calibrated?

Wow. I can’t believe the timing of this video. Last week out of nowhere I started experiencing very fast shots. I could not grind fine enough to slow down shots. I started to think there was something wrong with my recently purchased Ceado E6 V2. If I did happen to pull an acceptable shot that evening, The next morning it blew through the shot. Well, I decreased my blind pressure from 10 to 9 on my ECM Classica, both grinder and ECM purchase at WLL, it appears that the problem is solved. What happened to my 2 yr old ( 3 shots a day) machine

Where is the OPV on a rocket giotto type V PID?

I have Nuova Simonelli Oscar II and I dont know the pump type ?

Anyone knows how to adjust on BEZERRA ARIA?

My ECM Technika’s pressure is bang on 9 bar, but extractions are slow. Doesn’t matter how much I adjust my grind, extraction is always slow with pretty weak shots. One thing I have noticed is that my water flow seems to be slow when I lift the brew lever. What could this mean? (I have already cleaned/flushed my machine)

Very much appreciating your video's but this on is touching an issue for me. Pulling a 36g shot on 18g of coffee in 25-30 seconds with 3sec pre-infusion at 9 bar is a challenge. I am using quality freshly roasted coffee. To approach the correct flow rate, I am getting 14-16bar leading to a not so satisfactory taste. If I move to something close to 9 bar, by grind adjustment, my flow rate is too fast and I am getting around 60g+ of liquid coffee. It feels under extracted. Would adjusting the OPV in the vib. pump so max static pressure is 10 or 11bar help me reach my target?

If 9/10 bars is the ideal for espresso, how come the Gaggia Classic Pro (2019) comes at a higher 14 bars out of the box? Do you recommend people change it?

I've got a machine with a vibratory pump, but I'm pretty sure the pressure gage is measuring at the group, not the pump. How could I check to be sure?

Where can I get this machine to buy sir

My thoughts? Well, I think this video will trouble a lot of “prosumers” (and pros?) up to a level that they drop out of finetuning their espresso making skills. That is the only reason to write this exposé (and because I am a espresso-coffee lover). I first want to define the perfect brew process (by means of an espresso machine) to its basics. These basics are: 1. Accurate water temperature during extraction (defines extraction LEVEL); 2. time that water passes through the ground coffee (extraction TIME) and 3. pressure drop during the passing of the water through the puck (resulting in less or more crema) (GAS EXPANSION of volatile components). Experience with the equipment developed so far, has shown that when (fine) grinding of a defined/fixed amount of coffee is combined with a standardized amount of compaction you can create a resistance (friction) in the puck that results in a pressure build up of 9 bars above the puck and an extraction time of 20-30 seconds. Your machine has to be able to deliver that pressure. If you can adjust the max pressure of your machine to 9 bars and you happen to have prepared a portafilter with a more compact, thicker or finer ground puck resulting in a resistance of 9.5 bars then not ONE drop will be pushed through the puck. That would be a shame or not?! Most semi-automatic machines have a maximum pressure of +/- 15 bars. The only reason that it isn’t higher is that making a more powerful pump is more expensive and also results in much higher safety demands (boiler explosion; portafilter blown off the boiler); so it results in a much more expensive and much heavier machine. Suppose you have the same grind size and compaction and fix the portafilter to a machine that CAN supply 40 bars but where you can reduce the flow. Then you can get exactly the same perfect espresso with the same 9 bar pressure build up above and drop of pressure in the puck! Simply because it is the permeability (resistance) of the puck in combination with the flow level that defines the level of pressure that builds up above the puck. I am a soil scientist. Permeability of soil is extremely important to calculate how much water infiltrates through soil layers. I know a lot about the laboratory equipment (permeameters) with which the permeability of soil samples is determined (done in rings with similar diameters and heights of those of portafilters!). When also becoming a “prosumer” coffee brewer I saw that Darcy’s law (the law that defines the relations between grind size (we call that particle size distribution), compaction, water viscosity (temperature related!) and more, counts 1:1 to what happens in a portafilter/espresso machine. Pumps, like used in an espresso machine, produce a high flow (Quantity) at low pressure ((water)height) and a near zero flow when reaching maximum pressure (resulting in a pump-specific Q-h curve). For prosumer machines (equipped with cheap electromagnetic plunger pumps) such a curve is non-linear. This results in a much bigger difference between the flow at 9 bars and the flow at 11 bars; that is why finetuning the grind size/compaction in relation with extraction time is so difficult. Imagine a professional machine with a pump that can give a maximum pressure of 25 bars but with the same flow at 9 bars as a prosumer machine. Then, with the same grind size and compaction you would simply measure a 9 bar back pressure on the puck. The Qh curve of a 25 bar max pump is more linear at mid-range pressures (like 9 bars) what should result in an easier finetuning of the grind size and compaction as the resulting extraction time will vary less. When a 25 bar pump has a flow that is too large at 9 bars (so pressure above the puck would go up) this flow could be reduced with a flow controller better than with a pressure reducer! I suspect that a 25 bar pump mounted in a large pro machine with more portafilters will have a flow controller for each portafilter. Only for safety reasons the pressure could be limited to a useful maximum of e.g. 12 bars. In short: In my view forget about the maximum pressure setting screw for the ordinary prosumer machines and look for controlling the flow @9bars on expensive machines with higher pressure pumps to achieve the ideal 9 bars backpressure and extraction time. I hope you can appreciate this “thought”. Keep on the good work! Gerard’s Tips and tricks, the Netherlands

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Hi Mark, great information. I regularly watch your videos and very much perfected my espresso and milk frothing skills with your easy to understand basics. At 3:08, you mention recommended pressure as 10 bar for vibration pump machines, which is installed in most home espresso machines. Is there a specific reason for that apart from the working mechanism of the two pump types. In my own personal experience, my espresso machine (www.myespressino.com/uploaded_files/pdf/specs-1526898376.pdf) which has the vibration pump also gives the best flavour profile when the pressure reads 10-11 bars irrespective of other parameters. Until I watched this video, I had doubts about the settings of the pump or the barometer in my machine since the standard espresso pressure is known to be 9 bar which in my machine gives somewhat under-extracted shots. Going beyond 11 bars starts giving somewhat harsher shots as you mentioned. I have been using this great budget-friendly semi-professional machine from Indian brand for more than a year now.

for first time just tested my rocket and have 12 bar. mercy

nah... i still love my 5-7 bars

EFFECT! not AFFECT!

Great video, but your voice is wasted on KZfaq - you should be doing movie trailer voiceovers instead!