itsleighton Senior Member Joined: 17 Oct 2009 Posts: 45 Location: Texas Expertise: I love coffee
Espresso: La Marzocco GB5, PID Silvia, Grinder: Mazzer Robur E, Mazzer Major...
Posted Sun Jun 13, 2010, 6:51pm Subject: Heat exchange machine temp control
What am I missing when i read about the details of heat exchange machines regarding temperature control? Are most prosumer heat exchange machines regulated by thermostats just like the boiler machines? I am looking to upgrade to a machine I dont have to wait to cool down between , heat up for steam, etc, but I am not seeing obvious things about strictly dictating brew and steam temperatures.
Can someone please explain the basics to me? I PID'd my silvia, but to be perfectly honest, if I spend 2k plus on a machine, I dont feel like modifying it like I did my silvia. And I REALLY dont feel like having to argue again about warranties.
Leighton, if you're planning to spend 2K plus on your next coffee machine you can consider double-boiler machines (DBs) as well as HX machines. They can be more expensive than many HX machines, but some very popular choices are within your budget.
DBs can make temperature control even simpler and more accurately repeatable than HX machines. They are typically already PID'ed, and computer-control a brew boiler at the desired temperature for brewing, and a steam boiler at the temperature for steaming.
People made espresso for decades with single-boiler HX machines, and many still do. The excellent article Joel pointed you towards will give you a good sense of the art and technique of making espresso with them, and some people enjoy the extra operator participation and attention the art requires. But if simplest-possible repeatability and temperature control sound attractive, you may be a candidate for one of the three leading DB machines that have become so popular:
It's assumed that you have a very good espresso grinder already. If not, then you really need to budget for that too. A good espresso machine cannot be used to make good coffee if the coffee that isn't very freshly-ground to the proper consistency. If necessary, scale back your machine purchase (buy a less-expensive HX) in order to spend $450 or so on a Baratza Vario grinder, which may be all the grinder you need.
JasonBrandtLewis Senior Member Joined: 9 Dec 2005 Posts: 6,099 Location: Berkeley, CA Expertise: I live coffee
Espresso: Elektra T1 - La Valentina -... Grinder: Mahlkönig K30 Vario -... Vac Pot: Yama 5-cup Drip: CCD, Chemex Roaster: No, no, not another...
Posted Mon Jun 14, 2010, 7:04am Subject: Re: Heat exchange machine temp control
I don't mean to sound like a broken record, BUT . . .
The most complicated thing about temperature surfing on an HX machine is reading about it; actually doing it is a piece of cake. (Compare it to teaching someone to drive. If you have to explain each and every single step to someone, it sounds so complicated and impossible to master -- with something like 100+ steps before you can even start the engine! And yet, driving becomes easy, second nature, and yes, "a piece of cake.")
The difference(s) between an HX and DB machine are non-existent in the cup, which is after all where it counts.
Each class of machine has its advantages and its disadvantages, and each class has its "dedicated followers." Largely, but not exclusively, this boils down to what you're comfortable with -- i.e.: what they already own. For example, by temperature surfing, you can change/adjust your brewing temperature on an HX machine "on the fly," as it were. With a DB, you have to reset the thermostat, and wait for it to re-stabilize at the new (higher or lower) setting.
Which is best for any particular individual varies with that individual.
While I understand the sentiment in this statement it's really going too far. Yes, the grinder is a more important variable in many ways, but the espresso machine is more than just a hot water delivery device. It needs to supply the water at the right temperature (a fairly narrow band really) and also a fairly narrow range of acceptable pressure. If this weren't the case, we'd have much less need for upgraditis, PID's, pressure gauges attached to portafilter handles or paddle groups. The last part of the statement, buy the very best grinder you can afford, is certainly excellent advice. With a great grinder you get repeatability of grind and dose and make it much easier to focus on the remaining variables.
JasonBrandtLewis Senior Member Joined: 9 Dec 2005 Posts: 6,099 Location: Berkeley, CA Expertise: I live coffee
Espresso: Elektra T1 - La Valentina -... Grinder: Mahlkönig K30 Vario -... Vac Pot: Yama 5-cup Drip: CCD, Chemex Roaster: No, no, not another...
Posted Tue Jun 15, 2010, 6:45am Subject: Re: Heat exchange machine temp control
Mike, I am not the first person to say that, nor will I be the last. It's one of those "truisms" that's a cross between an aphorism and a cliché . . . but then again, clichés become clichés for a reason: they are true. Just don't take them too literally.
This is the first time I've heard this said and it's totally the case. I was really overwhelmed with this whole temps surfing, water dancing (I'm not that limber), mess of button pushing...but it's really no big deal. I'm going to start stressing this, thanks :)
Joel_B Senior Member Joined: 9 Oct 2007 Posts: 1,823 Location: Pacific NW Expertise: I love coffee
Espresso: Astra Mega II Grinder: Mazzer SJ, Virtuoso Vac Pot: Yama 5 cup Drip: nope, french press Roaster: Behmor, WP, BBQ drum
Posted Tue Jun 15, 2010, 8:38am Subject: Re: Heat exchange machine temp control
MikeReilly Said:
the espresso machine is more than just a hot water delivery device. It needs to supply the water at the right temperature (a fairly narrow band really) and also a fairly narrow range of acceptable pressure. If this weren't the case, we'd have much less need for upgraditis, PID's, pressure gauges attached to portafilter handles or paddle groups.
I'm with Jason on this one. It pushes hot water through a bed of coffee. PID's, pressure gauges, preinfusion, etc. may make the experience more forgiving and simpler, but from my (relatively limited) experience, the difference in machines isn't what's in the cup, it's how much work you have to do to get the same results.
I will say that some of the more entry level machines may not have the same potential of espresso as higher end machines (namely temperature stability), but when we're refering to machines in the $2K class we're far beyond that.
JasonBrandtLewis Said:
by temperature surfing, you can change/adjust your brewing temperature on an HX machine "on the fly," as it were. With a DB, you have to reset the thermostat, and wait for it to re-stabilize at the new (higher or lower) setting.
Symbols: = New Posts since your last visit = No New Posts since last visit = Newest post
Forum Rules: No profanity, illegal acts or personal attacks will be tolerated in these discussion boards. No commercial posting of any nature will be tolerated; only private sales by private individuals, in the "Buy and Sell" forum. No cross posting allowed - do not post your topic to more than one forum, nor repost a topic to the same forum. Who Can Read The Forum? Anyone can read posts in these discussion boards. Who Can Post New Topics? Any registered CoffeeGeek member can post new topics. Who Can Post Replies? Any registered CoffeeGeek member can post replies. Can Photos be posted? Anyone can post photos in their new topics or replies. Who can change or delete posts? Any CoffeeGeek member can edit their own posts. Only moderators can delete posts. Probationary Period: If you are a new signup for CoffeeGeek, you cannot promote, endorse, criticise or otherwise post an unsolicited endorsement for any company, product or service in your first five postings.
= No New Posts since last visit 