Sorry - The ECM Mechanika Slim V does have the thermosyphon restrictor. Page 10, Part # 33 for anyone looking in the future.

2.5mm flow restrictor then. Good job guys!

I would give bluenoser's suggestion a go. With the boiler at it's current settings (1.15) try a shorter flush at the beginning of your routine and see what starting temperature this gets you to.

There's still room to play with since that 2.2L boiler and 1400w heating element can produce a good amount of steam even down to 1 bar (on the pstat).

Cheers!

bklynjim wrote:Hey guys,
Thanks for the great advice. I was referring to lowering the pstat a bit, as I do think the 20 second flush is a lot. I'll see how much it effects the micro foam production and rebound.
Bluenoser - Are you sure there is a thermosyphon restrictor? I read in a UK forum that..." ECM hx machines do run cool because of the way they put plastic tubes inside the heat exchanger - they don't run thermosyphon restrictors." https://coffeeforums.co.uk/topic/43095- ... iler-temp/
I looked at the parts diagram but I don't see a thermosyphon restrictor or a "plastic tube in the HX but I might be missing it.
https://www.1st-line.com/wp-content/upl ... iagram.pdf

yup.. table 5 .. part #33.. 2.5mm restrictor.. Profitec and ECM are basically the same company and Profitec HX have had restrictors for a while. Not sure how the mechanika (regular works), but looks like the slim has the same type of restrictor as in my machine. Might have been redesigned slightly when they did this update. Next time your machine is idling at 205.. do a 10 second flush and wait 3 minutes and chart the group thermometer.. post here and we can see if it works similar to my Profitec HX.

I swear these HX machines are like black magic.. any change like adding a restrictor in the TS makes them behave quite a bit differently than older designs. It made the rebound in my machine really slow..

Edit: the previous 2 posts happened as I was writing

Yes.. just had my morning Cappo. Group was at 198.. Then flushed for 10 seconds (normally I don't this temp is fine).. Temp rose to 206 .. and after 10 seconds was still near 200. But after 1 minute dipped to 194.. then started to rise again.. In 3-5 minutes was back up to 197 where I pulled my shot. I never flush for 10 seconds.. most I do is a 5 second flush.. then wait and do another short one if I need to. If I find my idle is rising above 204 often, you are right.. maybe adjust the PSTAT down. This is where the PID is really convenient. It doesn't keep the brew water "rock stable" as the marketing hype says, but it does make it easy to change the idle temp. I've found that turning the steam wand on for about 20 seconds and waiting for steam pressure to build back up and then steaming gives me slightly stronger steam during the time I use it.

The restrictor in the newer designs was thought to limit the flushing you need to do.. But I find It doesn't really meet that goal. If you are flushing 20 seconds, then the water you are going through really makes this design worse than before.. as the bad thing about the restrictor is that the rebound is slower. In mine, I cannot make 5 drinks in less than about 45-60 minutes. And that is unacceptable. Fortunately, I mostly make 1 or 2.

I now time my morning drink. If you have it at the same time every day, just turn on machine with some auto timer for 30-40 minutes before you want it. This is the most efficient use of water. But change your workflow to use a "flush n wait" technique and you'll go through lots less water. I use a 'homekit' widget (Apple guy) and so I can also turn on the machine if I'm out (using iPhone app) but know I want an espresso in 30 minutes. I seldom flush now.

Hopefully you are use scale-free water to keep the restrictor clean.. I use RO water and add 3rd wave crystals, but there are lots of recipes for water here. It is one of the most important things to keep your machine working smoothly over long time.

I'm not sure ECM/Profitec know how to operate their HX designs. The manual with my machine is just plain wrong in many places. And you really can't find any info from them on proper flushing techniques. WLL and Clive have polar opposite instructions on using the Profitec Pro 500 PID HX machine. And no where will you ever find any info on actual performance parameter of their HX designs.. but I digress..

However, a very well-built machine..

Replying here because there seem to be several ECM and Profitec HX users in this thread:

I'm considering purchasing a Mechanika Slim, but the roast I tend to use is (by third wave standards) fairly dark, a city+ I'd say. (The beans are darker, but not at all oily.) My understanding is that the Mechanika Slim tends to run very hot, so I'm concerned that the brew water will be too hot for my blend. With a lengthy cooling flush, does the Mechanika Slim perform well on darker roasts? I tend to drink cortados and cappucinos, if that's helpful.

I'd appreciate any insight! Thanks all.

With my Technika, which might be very different, with the flush and go technique the grouphead thermometer shows a too high temp at first and then as the shot progresses shows about the temp I'm hoping for. I think it might take a little more than a short flush to cool the whole grouphead down and show correctly, I think Eric have stated that about the flush and go technique.

But 20 seconds is a long flush. I usually had to do 10 seconds when Idle, and a second shorter flush after prepping the puck. If not idle 5 seconds max.

bklynjim wrote:Hi guys,
I'm new to HX and trying to dial in my shots. I've ready everything I've found on flushing times and temperature but I'm still confused about the temperature profile I should be shooting for.

• Machine pressure set to 1.25 bar
• long idle temp is 208.5.
• RedBird espresso; 18g in 34g out in 34 seconds
• group head temperature peaks at 214.5 during flush,
  stop the flush at 209
• 203 - 202 during shot.

I took a video that I'd love you guys to critique. video

Thanks for the help!
Jim

Jim, Did you ever get it dialed in?

Sorry - just seeing this now.
I'd say I never stop "dialing it in" put here is my current work flow:

• • Flush for 6-7 seconds, temp goes to 214 during flush.
    Wait - 2-3 minutes for thermometer to reach 200 - 201.
    Pull shot temp stays about 204 through the shot.

So only real change is waiting for the temperature to drop a bit lower than I was when I first got the machine.

bklynjim wrote:I flushed more water and started the shot at an indicated 203 on the group head thermometer. Temp dropped to 200 - 199 over the shot.
Reading Eric's thermometer guide I think that should be about 196 - 197 at the puck. Tasted ok not great but the flow was also a little fast. I'm opening up the machine tonight to drop the pressure .1 bar.

I've pulled well over 100 lbs of Red Bird over the years. Like any fresh bean, you're going to get a lot of creama and a fast flow in the first couple days of opening the bag. I would not bother to adjust the machine to compensate. Seriously. Tighten the grind at the beginning of the bag until you're in the ballpark, and then change the dose as you zero in (~17.7 works well for me). After that, adjust your grind as the bean ages. I do not see this as a problem with the machine. This is all about dialing it in and taste. The numbers (weight, temp, time) are guides, not rules. Your tongue determines what's correct.