The Worst Thing about HX Machines/Heat Exchangers are evil

Need help with equipment usage or want to share your latest discovery?
User avatar
shadowfax

#1: Post by shadowfax »

I apologize in advance if this has been mentioned before, but I couldn't find it in the search. It's kind of an odd thing to search for, anyway.

This isn't an HX bashing thread. In fact, with my few years' experience with 2 different home HX machines and a few days' experience with a commercial Astoria HX, I would say that I love them as espresso-crafting tools, for their flexibility if nothing else. If someone handed me a good double-boiler machine, I wouldn't refuse, but I think I'd prefer to buy the equivalent-priced HX machine in most cases.

At any rate, that's an aside to say that there is nothing wrong with the HX design in my mind. The problem with a heat exchanger is people. People who don't care, and people who don't know.

I have a good friend who's in Los Alamos, NM. He used to work at a café on the main campus of the national lab there, and he was one of the baristas. They have a La Marzocco Linea 2 group at this site. Before he worked there, I used to watch the baristas make espresso. It was terrible to watch, and worse to drink. No one cared. They didn't have any idea how to clean the machine between shots, and they clearly had little notion of the importance of freshness or a proper tamp. My friend took it upon himself to learn how to do it properly. I returned to the café many months later, and he was making brilliant espresso. He had the Mazzer dialed in just right, and he had great form. He even learned to pour latté art pretty consistently. It was absolutely glorious to have--at last--a good café in Los Alamos, all because of the one barista who cared and learned.

Fast Forward a few months. His stupid manager moves him to a different, low volume location with a different machine. He was on a 2 group Laranzato. It looked like it had E61 groupheads (the modified ones with the solenoid-valve pressure release). He absolutely hated the machine. When I came to visit him, he made me a cappuccino. It was awful. I watched him flush some water from the group after a shot and realized that it was surely a HX machine. My friend didn't even know what this was--no one told him, because they didn't know! So, all the other baristas there are in the practice of brewing people "espresso" drinks brewed at upwards of 220° F! I explained to him about how HX machines work, and why you need to flush the part of the heat exchanger that's in the boiler prior to pulling the shot. After a couple of tries, he pulled a really nice shot that was easily on par with his work on the Linea.

That morning I had to drive back to school in another state. As I was leaving, I thought, man, HX machines are just evil! Such a great design, but so unintuitive. You have to do something (the flush) that you would never think to do unless you were familiar with the inner workings of the machine. And perhaps my point is moot, because if you really do care about making coffee, eventually you'll probably figure it out. But it makes me wonder how many baristas are working on HX machines in cafés that have managers who don't care, baristas that might take an interest in making good espresso if it wasn't horrendous all the time from the baked heat exchanger water. What do you guys think?
Nicholas Lundgaard

BradS

#2: Post by BradS »

I couldn't agree more. I've been the victim of more than one 220+ degree Hx shots from commercial establishments. I've since then thought that, in order to make an Hx idiot-proof, it needs a temp-control device coupled with a 3-position valve that would allow you to flush water overboard (or wherever) to a given temp, then shift the water to the group automatically. All you would have to do is set the proper temp...theoretically. Although with this additional hardware, you're likely approaching dual-boiler prices anyway.

Cheers,

Brad

User avatar
TimEggers

#3: Post by TimEggers »

Any barista who doesn't understand the mechanics of their machine (just one aspect of making espresso) won't make good espresso. Are HX's more susceptible to this? Perhaps. The root of the problem and it looks like you outline it well is the barista. I'm sure a clueless "barista" on an HX could murder the coffee worse than anyone.

It still amazes me what John Q. Public thinks is good espresso (or milk drinks). If people only knew...
Tim Eggers
http://www.facebook.com/TimEggers
LMWDP #202

User avatar
Randy G.

#4: Post by Randy G. »

Sven returns to the shop and says, "Jan, this wood chopper thing doesn't work as good as my ax. I think you ripped me off. It's so heavy and hard to swing, too."

"But Sven, you are my friend. I wouldn't rip you off. Let me see it." Jan pulls on the rope and the chainsaw starts up immediately.

A surprised Sven says, "WHAT THE HELL IS THAT NOISE, JAN??!"

Knowing the machine is not only part of use but part of maintenance as well. Ask Barry J. how many machines he has serviced that came to him with only about 10-20% boiler capacity left because they were so heavily caked with mineral deposits. I stopped in at a shop in Chico and looked at the machine on the counter, and thought to myself, "Hmmm... Never saw brown anodized portafilters before..."

If you don't know how to use the machine you are operating, it isn't the machine's fault.
Espresso! My Espresso! - http://www.EspressoMyEspresso.com
LMWDP #644

User avatar
cafeIKE

#5: Post by cafeIKE »

Sounds like the barista had an attitude about being moved. He took it upon himself to make the best espresso possible in location 1 and was content to serve dreck in location 2. :cry:

It's a poor workman that blames his tools.

avogadro

#6: Post by avogadro »

If you don't know how to do something, odds are you won't do it well. Either proper training or initiative, sadly, are missing in most establishments. When the shop I work at opened up they sent in a corporate trainer that advised we use the autofrother on the machine but "taught" us how to do it manually just in case. She also said that she likes to pull her shots at 18 seconds for faster service. No tamping of course. There was a lot of me nodding my head until her week with us was over.

As far as machines go, all HX's are not created equally. The actively heated E-61 types do indeed overheat when not under constant use however, our Aurelia is almost idiot proof. Even after an hour it is only off by a couple degrees (with a 30ml flush). Plus its dirt cheap and easy to service.

If a barista can't be bothered to manage temps or simply doesn't know any better it's likely they won't be grinding per shot, using fresh beans, or throwing out already steamed milk.

No excuses for bad espresso. Although, most people won't notice (*$).

This is what my local drive-thru franchise can do with an HX and a little initiative...Image

User avatar
shadowfax

#7: Post by shadowfax »

Randy G. wrote:Sven returns to the shop and says, "Jan, this wood chopper thing doesn't work as good as my ax. I think you ripped me off. It's so heavy and hard to swing, too."

"But Sven, you are my friend. I wouldn't rip you off. Let me see it." Jan pulls on the rope and the chainsaw starts up immediately.

A surprised Sven says, "WHAT THE HELL IS THAT NOISE, JAN??!"
After Jan shows Sven how to use the chainsaw, he thinks the chainsaw is awesome and quickly begins the process of deforestation with great efficiency.

... do you expect someone who doesn't have a manual, or any training, to figure out how to use a chainsaw? Good lord, Sven was darned lucky he didn't figure out how to turn it on and accidentally cut an appendage off.
Knowing the machine is not only part of use but part of maintenance as well. Ask Barry J. how many machines he has serviced that came to him with only about 10-20% boiler capacity left because they were so heavily caked with mineral deposits. I stopped in at a shop in Chico and looked at the machine on the counter, and thought to myself, "Hmmm... Never saw brown anodized portafilters before..."

If you don't know how to use the machine you are operating, it isn't the machine's fault.
Honestly, nothing is ever the machine's fault, really. Problems result from design/manufacturing flaws, or flawed usage. But there is tension between operator error and design error. Some things in life need to be trained. Too many, in fact. And I hate to see a machine that's not properly cared for as much as anyone in this room. But that's not really my point.


I have gotten several responses to the effect that my friend's error is ultimately his own fault. Personally, that kind of offends me. If it's anyone's fault, it's his boss who bought that machine and never bothered to learn how to use it himself or offered his employees any access to proper training.

My main point is that double boiler machines are simply more usable. Putting exactly the same interface on an HX as a double-boiler machine is, quite frankly, a design flaw. On a machine with a flowmeter and a dosage buttons labeled with cups, It would be a good design for an HX to also have a flush button; one attached to a little adjustable thermostat on the brewpath would actually be an extremely nice design. I would get better drinks in more places if everyone were using double boiler machines, regardless of how bad the managers train.

I am not saying I'd get great drinks, and double boilers aren't solving the real problem--Starbucks is an obvious example of that, the way they dropped their LM machines. It would be great if James Hoffman were at every Starbucks from Seattle to Miami. That's the way it should be. In the mean time, some mitigation of the current situation would be good.
Nicholas Lundgaard

User avatar
Randy G.

#8: Post by Randy G. »

shadowfax wrote:... do you expect someone who doesn't have a manual, or any training, to figure out how to use a chainsaw? Good lord, Sven was darned lucky he didn't figure out how to turn it on and accidentally cut an appendage off.
If Sven had a lick of sense he would have done some research, looked for manuals, Googled, researched, asked, or at least pondered before returning to the store and accusing his friend.

The parable applied, our barista friend should have done some taste testing of the product he was producing, and when he realized that they pulls were inferior to his attempts at the previous location, he should have said, "Uchhh. Something's wrong. I want to fix it. I want to make better coffee" According to the report, he did not. Did he even KNOW that there was a difference in the taste? To me, that story is the definitive difference between an employee who happens to make coffee and a Barista.
Espresso! My Espresso! - http://www.EspressoMyEspresso.com
LMWDP #644

User avatar
shadowfax

#9: Post by shadowfax »

Well, he's certainly not a barista in the Chris Tacy/James Hoffman sense--or, really, even approaching it.

But, he's a long way above the losers who really don't give a rat's behind. Yes, my friend suffers from some lack of initiative. I suppose that probably comes with getting paid about $10- 15 per hour, not to mention the fact that he is a poli-sci major who's working towards getting a job in his field, and trying to pay the bills. No, he's not an engineer like many of the people on this board, and he doesn't own 5-10 grand worth of coffee equipment either.

I do like HXes, and they are a great engineering design, and they can produce great espresso, and yes, baristas should care enough to figure out how to use them. But, I think that, at the least, HX machines could be made more user friendly. I would commend this book to those who really think this is all my friend's fault. I think it's kind of silly that the basic usage of something should have to be divined from a user manual or training.
Nicholas Lundgaard

User avatar
HB
Admin

#10: Post by HB »

shadowfax wrote:I would commend this book to those who really think this is all my friend's fault. I think it's kind of silly that the basic usage of something should have to be divined from a user manual or training.
I agree that HX espresso machines could be made more foolproof.

Eric's E61 thermocouple adapter goes a long way towards that goal; the next natural step, for those who want to use HX espresso machines with less hassle, would be automating the flush step. For example, an auto-flush sensor and interlock switch closed by the portafilter lock-in.

Specifically, install a grouphead temperature sensor that automatically cuts off the pump once the temperature is at or below the target flush temperature. To enforce the need to flush the group prior to an extraction, have the pump disabled if (a) the grouphead temperature sensor indicates it's above the target flush temperature, and (b) the portafilter is locked in. In other words, the barista can only flush the group when it's above temperature and the portafilter is disengaged; the barista can only engage the brew cycle if the portafilter is locked in (d'oh!) and the grouphead temperature is at or below the target flush temperature. If the portafilter is locked in and the temperature is above target, the pump will not engage, which hopefully will prompt said barista to reflect for a moment. :?

I thought about automating the flush using the SSR on a cheap PID, i.e., one "flush" toggle switch that would open the group solenoid and run the pump until the grouphead temperature reached X, a second switch to start brewing. It's more a curiosity than anything, the extra seconds required for the flush aren't that onerous to me.
Dan Kehn