How to use cheapo thermocouple?

[randomperson]

In order to get more scientific about my flushing with my new La Valentina (which I need to do since for the life of me I cannot discern the end of the water dance -- seems way too subtle on my machine) I got a cheap thermocouple device. It's the one jim schulman recommended, I believe -- but for the life of me I can't find the thread about it! (If anyone knows how I can find it -- something like the "$10 solution for temp management" or such -- I'd be grateful)>

Anyway, I threaded this thing up the single spout, put in a little foil to keep it in place, and then ran some water through after an hour warmup. The problem is the water pours out really quickly and even with extra foil (like a cup shape) I can't get any variance in the reading -- it just seems to hang out at around 95 - 96 degrees C from one ounce to six ounces flushed. But if I plop it in a glass of water it seems to immediately register the changed temp.

Any ideas on what I am doing wrong? I didn't expect this cheapie to be intensely accurate -- but I did expect it to show some variance as the flush progressed. Yikes -- unless my machine is malfunctioning! (I don't think so!!)

Oh I'm at a .95 setting.

Thanks!

[HB]

Jim's thread is linked among the FAQs and Favorites of this forum, The $10 Method for Temperature Tuning an HX Machine. Are you listening or looking for the end of the water dance? La Valentina was set to 1.0 bar for the video below. You can see the transition around the 25 second mark in this video:

Short idle period (< 3 minutes) after warm up flush (not shown). Result: 202.1F

To make these transitions easier to see, allow 3-5 minutes between espressos. Note the video above demonstrates a very short rebound (AKA, "flush-n-go") to produce a flatter temperature profile, not the longer "humped profile" rebound technique discussed in the review:

Listen for the hissing of steam and gurgling of boiling water before locking in the portafilter. Continue drawing water for about five seconds after the stream has settled down, for around six ounces total. Depending on the blend and your taste preference, the recovery time after the cooling flush is somewhere between 15 seconds (puck surface temperature briefly peaks about one or two degrees Fahrenheit above target brew temperature) to 35 seconds (puck surface temperature peaks around four degrees above brew temperature).

[another_jim]

Test the meter in boiling water, it may be **really cheap**. The one I used was accurate, but only updated about twice a second.

I used to just fill up the pf with crumpled foil, this slowed things down to about 2 ounces in 10 to 15 seconds.

[randomperson]

Thanks for responding so quickly!

I looked everywhere for that article except in the FAQ/Favorites section. Bah!

Dan, I can pick out the transitions in your videos within a second -- I just can't do it live with my own machine! Gotta try some more.

And Jim -- I mix up all my Jims! -- I am using the very thermocouple you recommended, so it should work. I'm gonna crumple up some foil and see.

Thanks for all your help!

I trudge onward!

[randomperson]

Oh one more thing, if you don't mind.

If you use the flush and rebound technique, do you flush down further than your target temp? If so, how many degrees (or seconds) further?

Similarly, if you use the flush and go technique, do you still flush down further than your target temp? I would assume you do, but for not as many degrees or seconds.

Any guidance you can provide will settle yet another quandary!

[HB]

To keep things simple, I flush the same amount and vary the rebound time to taste. The review advocated the rebound technique since it's generally easier to catch the desired temperature on the way back up than on the way down. With the added clues provided by Eric's thermocouple adapter, the flush-n-go is my preferred technique for La Valentina. As your questions suggest, you are intentionally passing the brew temperature slightly and then letting the temperature return in the first case; in the second case, the very short rebound is really more of a pause to allow the HX to stabilize.

If you're having difficultly recognizing the transition point, I recommend measuring the flush amount instead as suggested in the Buyer's Guide to the Quickmill Vetrano:

If all this talk of listening to cooling flushes has your head spinning, below are Bob Yellin's keep-it-simple rules that work well:

1. If the machine has been idle for awhile, flush 6 ounces
2. Or, if the machine has been idle around three minutes, flush 2 ounces
3. Wait 30 seconds and start the extraction.

That's it!

You may have to adjust the rebound time in step 3 slightly given your pressurestat setting. My guess is around 20-25 seconds.

[randomperson]

Ahh, that's the ticket! Would simply flushing 6 ounces work even if it was the first shot of the day? I've been preparing my shot first, then flushing, then pulling. BobY (elsewhere, I believe) suggested pulling 6, then preparing the shot (in under 3 minutes, I presume!), then flushing another 2 ounces, then pulling. Would both techniques work equally well? And I assume if I wanted a cooler temp I should shorten the rebound or eliminate it altogether.

I wonder if I should lower the pressurestat. Mmmm. I thought .95 was pretty lowish. I don't want to unscrew her just yet -- she's too new (and so am I).

I PM'd erics about his upcoming modified thermocouple adaptor (the one with the three minute installation routine) -- I NEED his device!

Nonetheless, despite all my issues I do love the machine. I love her looks and the solid thwap as the heating element turns on and off. I love being able to leave her on most of the day. And my houseguests thought my shots were superb (they sucked, really -- after all, I'd only pulled about three shots or so last night before my debut with guests this morning --but cappas hide a multitude of sins!). It all felt very festive this morning -- and I've only had La Val for two days!

[HB]

Ahh, that's the ticket! Would simply flushing 6 ounces work even if it was the first shot of the day? I've been preparing my shot first, then flushing, then pulling. BobY (elsewhere, I believe) suggested pulling 6, then preparing the shot (in under 3 minutes, I presume!), then flushing another 2 ounces, then pulling. Would both techniques work equally well?

I agree with Bob, a "warm up" flush prior to the actual brew temperature flush helps stabilize the group. You can see the consequences in this video where I overshot the flush and missed the target temperature by 1.5F even with the aid of a thermocouple readout. Without it, I could have been off by double that. All espresso machines that I've worked with are happier with a wake-up call before getting down to business (the GS3 being the sole exception).

Long delay (10 minutes). Result: 200.0F

Trust me, three weeks from now you'll be giving instructions to others. The key is getting the extractions consistently correct so you'll be able to accurately judge temperature differences. With all this temperature hullabaloo, many forget that's the harder skill to master.

[framey]

Nice hat Dan

[randomperson]

Thought I'd give a progress report.

This good news is that things actually seem to be coming together!!

For one thing, the "Lazy Broad's Flushing routine" seems to be working really well -- 6 oz flush (sometimes 5.5 for kicks) plus a 20-25 second rebound produces very good shots -- not Godlike, yet, but very very good. This is particularly interesting because as luck would have it my .1 gram scale died two days ago (probably because I spilled hot water on it one too many times as I turned on the hot water tap thinking it was my steam knob!) so I am having to dose by look and feel rather than by gram. So naturally there is some inconsistency! So I am particularly impressed by the quality of the shots absent my gram scale.

It also proves Dan's point about the relative forgiveness of these E61 machines vs single boiler ones in terms of dose and tamp.

It could also be my imagination but in my mind's eye I am starting to think I can hear the end of the flash -- but only if I cock my ear right next to the group head so that I can hear the sputter over the noise of the vibe pump. This could be my imagination, but we'll see!

If my ears are correct, it looks like a 5 minute idle needs a four ounce (total) flush (flash plus 10 count), vs a 10 minute idle and its 6 oz flush, vs 2oz for an under 3 minute idle time. Are my ears deceiving me or does this sound like it might make some sense?

I am also noticing that I can tell how a shot will taste simply by sniffing it -- the sour or bitter notes will dominate if the shot is poor, and if the shot is on the money the smell is simply roasty.

As for microfoam -- well it is truly an amazing thing, this machine! It steams forever, and the microfoam (when it comes together -- which is now most of the time) is simply gorgeous -- absolutely unachievable with my Gaggia. And I love how it's ready to go all the time! I am purging the wand until the light goes on, then waiting until the pstat goes up to the top of the cycle, as Dan suggested. With this setup, I can steam until the cows come home! (I am in Vermont after all!)

Now, the pstat -- seems to hang out at around .9 but tops out at 1 and bottoms out at around .6 -- all of this within the "red section" of the gauge, so that would seem to be the appropriate setting. I had asked for a setting of .95 so I assume this range is correct. Does it seem ok to you all???

Will keep you posted -- am still seeking best possible shots, so clearly have some learning to do -- but I am pleased by my progress so far and have only had La Valentina since last Friday -- just 4 days or so to get this far!

Do let me know about my simplified flush routine -- does it seem OK to you all? (Goal temp is around 198-199).

Oh and as for the cheapie thermocouple -- I've abandoned it, as it doesn't seem to register any temp changes! Must be the nature of how it's placed in the basket!

Thanks again for all your help!

[HB]

Sounds like you are progressing very well.

If my ears are correct, it looks like a 5 minute idle needs a four ounce (total) flush (flash plus 10 count), vs a 10 minute idle and its 6 oz flush, vs 2oz for an under 3 minute idle time. Are my ears deceiving me or does this sound like it might make some sense?

Your ears are correct. That's the distinction I make between "idle" and "really, really idle". I prefer to give HX espresso machines a wakeup call flush then go about preparing cups, clearing the grinder, etc. By the time I'm ready, it's ready for a second flush and a lot calmer, as you noted. Vibe pump noise isn't an issue for me since I "outboarded" it to the cabinet below.


You call that a flush? The Elektra A3 is a fire-breathing dragon

[randomperson]

Well I owe all my progress to you, Dan!

Tell me -- that second flush -- technically, is it a warmup flush? Ie, you cool things down with six ounces (flash plus an 8 to 10 count), then do you stuff, then flush 4 oz (total) or so after 5 minutes or so. Is that second flush of four ounces warming things back up to temp or continuing to cool things down after things have warmed up again?

You see I am after complete and total understanding!

[HB]

The answer is always the same: The heat exchanger is cooling down during a flush and the group (grouphead) is warming up. An extra flush-wait-flush-pull more closely simulates a cafe's rhythm.

[another_jim]

The answer is always the same: The heat exchanger is cooling down during a flush and the group (grouphead) is warming up.

Eventually the grouphead may cool down too, if the water debit is high.

[randomperson]

Now things are really starting to make sense!

I'm now seeing how you can vary the flush or rebound to change the character of the shot. After my wake up/walk up flush I then built my shot and tried flushing 4 oz. Too sour. Built another shot and flushed just under 3 oz and the result was spectacular! I'm hoping to get to the place where I can figure out what my rhythm is (per Jim's suggestion) and nail with some consistency from shot to shot. Of course this will be complicated when I add steaming into the mix, as I tend to build each drink one at a time. So I'll probably have to increase the shot to shot flush slightly when I do that

That flush wait flush pull thing -- closer to a cafe rhythm as you said -- it's all starting to fall into place.

Whew! I was starting to think it was like one of those horrific subjects in business school -- like accounting or options analysis -- that was just too much to think about! But I see it is a combination of rules of thumb and getting a feel for how it all works. Ideally what I'd like to do is really be able to nail when the flash ends and count from there rather than running by the numbers as I am doing right now. But I feel there is hope!

Oh and the pstat -- normal to sit around the target of .95 but peak at 1 and occasionally (when steaming) drop to around 6 or 7?

Thanks again for all your help guys!

[randomperson]

Oh one more thing -- is there a pace at which flushing between shots is unnecessary? I'm thinking not, given how quickly the machine recovers I suspect it overshoots rapidly as well.

[HB]

Oh one more thing -- is there a pace at which flushing between shots is unnecessary?

Jim's The $10 Method for Temperature Tuning an HX Machine would help you determine that pace. I'm not fast enough to worry about getting ahead of its recovery, i.e., Bob's simple rules apply.

[cannonfodder]

It is enjoyable to watch someone progress from the frustrated, 'how do I do this, what did I get myself into' stage to confident and developing. I remember well the day I had that light bulb moment. After reading trying reading questioning reading etc... it just fell together one winter day. That light bulb came on and it all fell together. Now it starts to get fun. Practice a lot, enjoy the journey and ask questions. The combined knowledge on these forums is incredible. It runs the gambit from first time user to world class baristas.

Then when I think I have a solid handle on it and get feeling smart, I read, or re-read one of Jim's data-logging monster threads and realize how much more there is to learn.

To the flushing routine, there are days I wish I had a smaller machine. I resurrected an old Faema two group this winter, big boiler and huge heat exchangers. After an hour and a half heat (yes it takes that long to properly heat) I flush 8oz into my awaiting cup. Then I sweep out the grinder hopper/chute, flush another 4oz, grind, flush another 2oz, level and tamp, flush another 2oz then lock and go. This monster is made for continuous use so more than a few seconds and it needs flushed and my boiler is only at .8 bar. I need to tweak it down to .7-.75. Even at those low pressures, it steams in seconds thanks to that big honking boiler.

[randomperson]

It is enjoyable to watch someone progress from the frustrated, 'how do I do this, what did I get myself into' stage to confident and developing. I remember well the day I had that light bulb moment. After reading trying reading questioning reading etc... it just fell together one winter day. That light bulb came on and it all fell together. Now it starts to get fun. Practice a lot, enjoy the journey and ask questions. The combined knowledge on these forums is incredible. It runs the gambit from first time user to world class baristas.

Then when I think I have a solid handle on it and get feeling smart, I read, or re-read one of Jim's data-logging monster threads and realize how much more there is to learn.

To the flushing routine, there are days I wish I had a smaller machine. I resurrected an old Faema two group this winter, big boiler and huge heat exchangers. After an hour and a half heat (yes it takes that long to properly heat) I flush 8oz into my awaiting cup. Then I sweep out the grinder hopper/chute, flush another 4oz, grind, flush another 2oz, level and tamp, flush another 2oz then lock and go. This monster is made for continuous use so more than a few seconds and it needs flushed and my boiler is only at .8 bar. I need to tweak it down to .7-.75. Even at those low pressures, it steams in seconds thanks to that big honking boiler.

cannonfodder -- Thank you so much for those kind words!!! I'll admit to a fair amount of embarrassment on my part -- after posting all these basic questions. It has made me feel more than a little foolish. That said, having asked everything under the sun (so far!) I find I am actually getting somewhere!! And I certainly would not have if I hadn't asked.

And yes, the collective wisdom, patience and willingness to help from these forums is simply amazing! I am one of those people who loves learning new things, but usually you have to do that on your own. The fact that there is this fantastic real-time resource, right here, is a wonderful thing!

This espresso business -- truly a magnificent obsession. There is fine machinery involved, and art and science and engineering and more than a little luck too. It is just so much fun! I am loving this pursuit and am enjoying the journey too.

As for flushing -- well, it is a thing, to be sure, especially since I need to use bottled water as no purification system exists (to my knowledge) that can handle sulfurous well water. If I had your machine I'd need to get water delivered by the truckload!

Your machine sounds truly wondrous -- I'm sure you love its capacity and power, even if she is a thirsty devil!

Thanks again for your vote of confidence in my progress!

[randomperson]

Further progress report:

I am proud to report that my "walk up" shot routine has become brilliantly consistent. 6 oz flush, prepare shot in under 3 minutes, flush two ounces, wait 20 seconds, pull. Result? Sweet espresso, thick crema -- not a trace of bitterness or sourness. And this with Terroir Southern Italian SO Daterra -- not as finicky as their Northern Italian, but not the most forgiving espressos out there!

I am thrilled!

My next task is to see if I can build back to back cappas with the same consistency. I suspect I'll have to add a minute for the steaming -- meaning I'll be ready for my next shot in about 4 - 5 minutes rather than 3. Will the portafilter wiggle and steaming process make the 2 oz rule still relevant? Or will the extra minutes require a longer flush before the pull even though I've drawn off some cleaning water plus steam?

I'll be sorting that out this afternoon -- but all your thoughts are welcome!

This machine makes fantastic espresso -- truly fantastic. And she is a joy to use!

Thank you thank you Dan!