Seeking low tech way to measure brew temperature

Beginner and pro baristas share tips and tricks for making espresso.
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#1: Post by ron45 »

The subject pretty much covers it. I saw a reference to using a styrofoam cup but there were no particulars.


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#2: Post by barry »

foam cup method:

take a small foam cup which will fit up against the group gasket (6oz is about the right size), and push a dial stem thermometer through the side about an inch up from the bottom. angle the thermometer stem downwards across the cup and wedge it into the opposite bottom corner. to measure brew water temp, remove the portafilter from the machine and hold the cup firmly against the group gasket on the underside of the brewhead in such a way that you can see the thermometer dial. run about 2oz of water into the cup and watch the thermometer dial for the maximum temperature reached. it's easy to get burned doing this, so be careful not to let hot water run onto your hand.

i've got illustrations someplace....

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#3: Post by another_jim »

Welcome to the boards.

Cheapest thermocouple and meter on the planet. Greg has no reason to be scared, but it will measure your average shot temperatures to the nearest degree accuracy. Either make up a schomer style temperature measuring PF (or basket if you have a naked one), or just thread the thermocouple (which is a plain wire) up the spout of the PF and stuff some tinfoil into the PF so the TC stays submerged. The water will flow too fast, but the average reading from 3 ounces of water will be within a degree of what you get using more sophisticated devices.

You will need more expensive gear to get a profile over the course of a shot -- a recording meter and a specially made basket either Schomer or Scace style.

For permanent monitoring, many people strip off the outer insulation of the TC's wire pair and run the two thin wires between the group gasket and the PF-basket lip, attaching the probe to the shower screen. The wire will eventually break (mine always within a week), but some people have gotten a few months service out of the arrangement. The more permanent continuous shot monitoring installation requires drilling and plumbing the grouphead. This is well above my skill rating -- check with Barry, Greg, Andy, Sean, Mosfet, Lino or any other mad machine modders I may have missed.

ron45 (original poster)
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#4: Post by ron45 (original poster) »

Barry, Jim, Thanks for the info. I neglected to say how pleased I was to come across this forum. The resources area is a machine tweakers delight. I got the link from Anthony at Caffe Fresco. I'm anxious to try his espresso blends as well as the SO one he's roasting in the N. Italian sytle.


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#5: Post by Rybolt »

another_jim wrote:Welcome to the boards.
Link is dead for me, any alternatives?

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#6: Post by ddr »

I do not have a thermometer either, I was thinking of ordering this one:

or this one: ... B00009WE45
LMWDP #242

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#7: Post by Frost »

Here's one I use for roasting. It checks accurate for boiling (.....after a calibration :shock: ) but many others have gotten these accurate right out of the box.

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#8: Post by cannonfodder »

Boy, reviving an old thread. The thermocouple may no longer be available because the original posting was 4 years ago. An instant read thermometer from the local kitchen supply store will work. You can usually pick up a type K thermocouple multimeter on EBay pretty cheap as well.
Dave Stephens

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#9: Post by erics »

A nice thermometer is the Taylor 524 as described here: ... ochure.pdf
The "out of the box" calibration is usually easily within +/- 1 degree F. Checking thermometer or thermocouple calibration in boiling water is typically a hit and miss affair because of convection currents in the water. Sticking the instrument in an ice slurpy mix or condensing steam is much better.

Eric S.
E-mail: erics at rcn dot com

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#10: Post by TUS172 »

Yep, I went ahead and ordered one of these: Shipping was not that great but what the hey... :shock:
It will be great to have one of these around to periodically have the option to check what my 2nd 3rd or 4th pulls are doing. Having the Boiler gauged to pressure and the Ceme pressurestat set fairly tight is one thing but to get that accurate measurement from near the screen will be of great value. Thanks for the revival of this thread.
Bob C.
(No longer a lever purist!)
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