How tinkerers brought PID temp control to espresso machines

http://home.lamarzoccousa.com/history-of-the-pid/

by troydavis • 11 years ago

51 45 11 years ago

home.lamarzoccousa.com

acveilleux• 11 years ago

PIDs are great for espresso boilers where you want water around 202F (sea level), so below boiling. My home machine with an 800ml brew boiler stays within +/- 2F all day with the PID. My previous machine without PID could barely keep it in a +/- 5F range.

For steam boilers, pressure stats are actually quite effective, especially as they get larger.

rmccue• 11 years ago

(202F ~= 94C)

adevine2• 11 years ago

Interestingly, I've read an article that explains why it's easy to make a great cup of coffee in Denver. The boiling point of water in Denver is 202, so you can add coffee to boiling water and it's right at the right temp (something that would be a big no-no at sea level).

tzickles• 11 years ago

link? would love to read!

nicpottier3• 11 years ago

I was in Vivace's the other day and Schomer's latest quest seems to be around water. As I understand it they are starting from purified water then adding in their own blend of minerals to achieve the consistency they want. (apparently only the Capitol Hill location is testing this, more here: http://espressovivace.com/index.php/water-formulation/)

I have a PID'd Silvia (https://www.seattlecoffeegear.com/pid-retrofit-kit-for-ranci...) and it does make a difference. But man, the black hole that is making repeatable excellent espresso at home doesn't end there. You start wondering about your tamp pressure, need a $700 grinder to have consistent adjustable grinds and start roasting your own coffee.

It is an expensive hobby, but a tasty one at least.

If you pass through Seattle, make sure to drop by Vivace, they define what proper espresso is.

RogerL• 11 years ago

I PIDed my Silvia as well. Seems to work well, though my heat exchange machine w/o a PID seemed to make better espresso (at several times the cost). These days my schedule has me leaving early so the machine is gathering dust in the garage.

When I was in Seattle this spring I made a tour of Vivace, Victrola, et al. Really fantastic stuff going on there. Here in the bay area everyone seems to like sour notes. I feel I beat out all the local shops with my home setup. Schomer definitely beats me out, though.

sp332• 11 years ago

How is a $700 grinder better than any burr grinder?

peapicker2• 11 years ago

I've had cheap (~$100) burr grinders and still got too much dust in my ground for a proper-tasting espresso. Bought a Nuova Simonelli MCF (back when they were $350 instead of $600) and the commercial-level burrs and worm-gear infinite grind adjustment made my espresso incredibly better. Details on features of a grinder like this:

https://www.seattlecoffeegear.com/nuova-simonelli-mcf

Retric3• 11 years ago

Ego.

PS: Most people fail blind taste tests with this stuff. But, just like the high end audio market spending money on junk makes some people feel good.

draker• 11 years ago

Commercial coffee grinders are periodically calibrated to ensure they are providing the proper grind. When new both the $100 unit and $700 unit would likely provide similar results. Over time the commercial unit (built to handle higher volume) would remain in-spec without calibration for a consumer user whereas the grind of the $100 unit would likely degrade from wear.

swagv• 11 years ago

What's an unforseen side-effect of so many people posting about their PIDed Silvias on the Internet that I noticed people who were hesitant to buy a Silvia because they thought too many people were manually correcting for a design flaw.

robohamburger• 11 years ago

That is a good point. It works pretty well once heated up or if you time when you pull your shots.

deutronium2• 11 years ago

PID temp controllers are also used a lot in homebrewing especially for controlling mash temperature.

You can use the PID to maintain the temperature of the wort at ~65C by passing the wort through a heating element and a temperature probe (this is called Recirculating Infusion Mash System).

michael_h• 11 years ago

I've found that the mashing temperature of the venerable 'huge cooler wrapped in bath towels' is unbelievably stable.

deutronium2• 11 years ago

Yeah, that's true, although using RIMS/HERMS lets you performed stepped mashes too and to some degree helps with clarity as the wort is constantly filtered through the grain bed.

ascorbic• 11 years ago

Agreed. Much as I love shiny kit, and RIMS/HERMS seems fun, I've never had my big cooler mash tun drop by even one degree C over 90 minutes, even without bath towels.

attaboyjon• 11 years ago

Before we had reasonable espresso in Austin, I had my own PID'd Silvia. I had had good coffee Vivace in Seattle and wanted to replicate it.

But boy was it a lot of work, your home-roasted beans have to be the right freshness, the milk has to be super fresh and your tamping technique has to be spot on.

Now that we have good coffee in Austin I cant see going back to doing it myself.

adevine2• 11 years ago

Meh. I live in Austin, and I have yet to find a shop that makes espresso drinks as well as I do (at least to my taste).

Don't get me wrong, Austin has some great shops. However, I feel like there was such a strong move away from the "burnt Starbucks norm" that all of the good shops feature extremely light roasted coffee that, IMO, doesn't stand up in milk drinks well and is usually way too acidic for me. If you know of a place that serves a great medium-roasted, chocolatey/nutty cappuccino, would like to find it!

jowiar• 11 years ago

Much like there was a "hop escalation" in IPAs, there's definitely been a "sour escalation" in coffee. It's fallen off a bit in recent years, but around 2012, it was bad (I'm looking at you, Intelligentsia!).

Roasters became accustomed to the sourness of the coffee, to make each new coffee taste "right", they had to make it more, and more sour. For those of us who didn't consume coffee in quite the volumes of the professionals, it didn't go over well.

the-dude4• 11 years ago

Well, I just have to shamefully plug the meCoffee PID ( https://mecoffee.nl ). The product is just picking up a bit of steam.

Disclosure: mine.

mantesso• 11 years ago

Looks interesting. Can it be installed on a Gaggia Classic?

the-dude4• 11 years ago

Thanks. Yes it can, we already acquired a Classic and will produce a manual and video for it. But we can guide you through by email.

The meCoffee can be installed in practically every espresso machine which has no electronics of it's own. It is Faston(tm) connectors all the way down...

peapicker2• 11 years ago

Super cool! I'm tempted to up my Silvia's game (I've a v2 from ~2003), but the lack of iOS app has me less likely to go there -- although I know you're just getting off the ground and things take time. Nice work all around!

the-dude4• 11 years ago

You should definitely PID your machine, the increase in taste and consistency is amazing.

polishninja• 11 years ago

PID Controller, if you don't know what one is. (I didn't) https://en.wikipedia.org/wiki/PID_controller

ashmud• 11 years ago

If you've worked in industry and/or programming PLCs, you've probably come across PID loops before.

Maybe not as accurate, but a simpler explanation: http://plchowto.com/plc-pid/

petra• 11 years ago

I'm curious: Since the problem was clear to anybody in the field - temperature control, and there's a whole field dealing with control where PID is bread & butter,so it's quite simple to ask for a solution , why did it take something unique and tinkering to add PID to coffee machines ?

why didn't companies in the field just implement this as part of their product development(maybe aiming for the higher end) ?

the-dude4• 11 years ago

I was told by a professional coffee technician manufacturers experimented with electronic temp sensors 15-20 years ago but they were prone to failure. Field service is expensive. This is for the professional machine ( 2 - 3 groups ). They have always used pressostats which are very reliable but they wear due to arcing.

For the home market, lots of machines are not heat-exchangers and therefore need to run a lot cooler ( 100c instead of around 120c ). A pressostat does not work well in this range and they just mount cheap thermostats.

abernson3• 11 years ago

This is more or less what I've heard. Early espresso machine tech was based off mechanical relays, and they didn't play well with early electronic temp sensors. Also, temperature stability was not really a thing anyone was talking about to that degree, so it wasn't a priority for manufacturers until noise was raised.

brunoqc• 11 years ago

Is there any proof that a PID is worth it?

abernson3• 11 years ago

Hi everyone, I'm the post author. Feel free to ask me any questions and I'll answer as best I can.

thatcat• 11 years ago

Does anyone know what the thermal stability system, which is more precise than the PID on the graph represents?

abernson3• 11 years ago

Hi! Disclaimer, I wrote the piece for LM.

That's a graph from La Marzocco's internal documents and represents the total heat stability architecture of their machines, including boiler and grouphead design, preheating, tuned PIDs, etc.

caligastia• 11 years ago

Anybody had espresso from a Mirage?

http://www.keesvanderwesten.com/mirage-special-features.html

Awesome use of a PID loop.

lafar6502• 11 years ago

is anybody buying $7K home coffee machine + only $500 for side panels and $200 for flexible steam pipe?

How tinkerers brought PID temp control to espresso machines

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