Double check your thermometers

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Diablotastic

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Just thought I'd share an issue i had on one of my recent batches.

I did a Pale Ale in my garage recently and I had lost about 10pts on my efficiency. Now initially my thought was that I didn't sparge hotter eough given the garage temp which was probably around 40 degrees.

Now this may have played some role in my issues but on my next batch I decided to double check my digital probe thermometer with a $3 analog therm and my ploar ware brew pot therm and low and behold It was anywhere from 5-8 degrees higher then the analog units.

So it seems that I was mashing/sparging with much cooler water then I had thought I was on my previous batch.

My most recent batch (using the two analog/dial thermometers) I was able to get my Eff back up over 70% where it generally is.

Originally when I 1st used my digital probe unit it was accurate as I checked it against two other units. It seesm that after about 5 batches it had fallen way outta calibration...even after battery change

Just:mug: some food for thought
 

Zymurgrafi

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double check, then check again.

and aGAIN! AGAIN!!!!







TRUST NO ONE! Especially not THermmomobbbers!!!!



THEY LIE!!!!!!!!!










:drunk:
 

shamrock

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Agree!

I have a floating analog, an analog dial type, and a few digital thermometers. At any given time, they all read different temperatures (3-5 degrees) and one of the digitals is way off (10 degrees). That digital almost ruined my first AG batch.

I would recommend to anyone that they at least borrow a few thermometers for comparison and make sure the one you're using isn't completely borked.

I use a digital with a long probe for mashing with the readout on the outside of the MLT, but now I always throw the floating analog in the tun as well just to double check.
 

BOBTHEukBREWER

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Check in boiling distilled water, and in distilled water ice which is 75% melted, this will tell you if the device is consistent across the 0-100 range. Then find a friend who works in a laboratory, and get it calibrated at 65 Deg C. My own digital one reads 1 deg c low at 65 deg C (hospitals, food industry, QC dept in a plastics factory etc etc )
 

eriktlupus

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the dial therms are bad news after a feew brews. i must have bent or twisted mine last fall. i normally don't stick thermometers in the kettle while boiling, dud i know how hot that is 210,here, and theres no reason to check it, but when i did an AG brew indoors i stuck it in to help control when a boilover may occur lo and behold it was reading 225-230 before the wort started boiling! this now explains why my efficiency has gone downhill the 4 brews or so. bought a new digital remote probe type and efficiency wemt up to 92%,not neccasarily a good thing with the low ibus i had built into the recipe but if the next one is as good i'll be happy then.
 

Skins_Brew

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Thermometers are the single biggest point of failure for me. I had a probe (Pyrex, but a lot of the probe thermometers all look the same with the exception of the brand) that read like 10* off a Digital Polder Thermometer. I blame these SOB thermometers for getting like 50% eff on my smash I just made. I am going to invest in a good thermometer as my next homebrew purchase.

Edit: Agreed. Dial therm suck sh*t too. I had one of those and it started f'ing up.
 

PvtSkippy

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Don't be like me and forget to take altitude and barometric pressure into account when calibrating with boiling water. The thermometer I thought was off by two degrees was actually off by eight when I factored in altitude. Didn't exactly do wonders for my mash temps. :(
 

Seabee John

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I use between 3 and 6 different thermometers, 2 dials, two digital "pen" style and 2 digital style with the thermocouple on a wire lead. I do a bath test before hand and exclude and replace any thermometers outside the common temp between the rest.... and I'm still nervous they might be off.
 

bull8042

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I use between 3 and 6 different thermometers, 2 dials, two digital "pen" style and 2 digital style with the thermocouple on a wire lead. I do a bath test before hand and exclude and replace any thermometers outside the common temp between the rest.... and I'm still nervous they might be off.
WHOA there John! That is some pretty serious paranoia you got going on there.... You might want to look into some sort of "thermometer support group" or something.... ;)
 

Seabee John

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WHOA there John! That is some pretty serious paranoia you got going on there.... You might want to look into some sort of "thermometer support group" or something.... ;)
I've already joined one.... I brew with Slnies and Nicksteck.... they keep my thermo-paranoia in check
 

abeeraday

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I have two of these and love them. General MDP300PP Mini Digital Panel Meter with External Sensor General Tools & Instruments Formerly Mannix MDP300PP MDP 300PP

I even leave the probe immersed for the duration of the boil and I have had no problems whatsoever.
Thanks for posting that product link. I found out this morning my prob thermometer is way off. I used it to monitor the temp in my fermenting cooler. The digital read 60, when I used an analog, it read 38 (the water bottles were still frozen after 12 hours in the bath, so I knew the water was colder than 60)

Thanks again :rockin:
 

bernerbrau

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Thanks for that, I just got a $20 digital instant-read from Target. Will remember to double-check with the analog thermometer.
 

COLObrewer

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Glad I'm not the only one.....&%*$&#(&^&$#@@&*^ thermometers!!! What about infra red ones? Is there such a thaing?

Bottled: Pine Stout, Heather Ale, Sage Mead, Corn Stalk.....Beer?
Primary: Earl Grey Pilsner.
Secondary: None
 

Seabee John

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Glad I'm not the only one.....&%*$&#(&^&$#@@&*^ thermometers!!! What about infra red ones? Is there such a thaing?

Bottled: Pine Stout, Heather Ale, Sage Mead, Corn Stalk.....Beer?
Primary: Earl Grey Pilsner.
Secondary: None
sure there is such an animal... looks like a little radar gun, the one I used even had a laser to pinpoint the surface you were reading... it might me good for checking the temps from across the room :)
 

Denny

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I've had thermometers that were on at freezing and boiling, but off at mash temps. Since I don't mash at either freezing or boiling temps, I bought a lab calibration thermometer and use that to calibrate my brewing thermometers.
 

Buford

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My dial "cooking" thermometer and my floating glass one are both off. The dial one reads low 2 degrees at both boil and in ice water and the glass one is off by at least 6 degrees too high in ice water.

At least the Brewmometer on the kettle has an adjustment screw, so I can trust that one after I set it.
 

Denny

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Glad I'm not the only one.....&%*$&#(&^&$#@@&*^ thermometers!!! What about infra red ones? Is there such a thaing?

Bottled: Pine Stout, Heather Ale, Sage Mead, Corn Stalk.....Beer?
Primary: Earl Grey Pilsner.
Secondary: None
Yeah, but they're not much good for checking mash temps since they only check the surface.
 

COLObrewer

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I see, I guess the key is calibration then...... But I kinda like the idea of sitting across the room and shooting at everything to see the temp while sipping on a cool homebrew..... How about an x-ray infra-red thermogun? Heheh. .. . . . with auto sample extraction . . . . beam in my beer scotty.
 

BullF-16

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I just dropped 90 bucks on a Thermoworks Thermapen. Should arrive by my next brew day. I got tired of the inconsistencies of my cheap analog and walmart and Target digitals.
 

antsp1

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For you cheapos like me out there. I have one of these, and I can pretty much calibrate everything else from it.

If you like the digital kind try this one, its the (SKU 45-4342). It supposed to be super accurate (+/- .4 F).
 

RCCOLA

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Just ran into this problem myself.Mashing 8deg. too cold .My marzen finished at 1.008 Ouch!!Are the laboratory thermometers the most accurate?It runs exactly with the digital that showed my dial therms. were wrong.
 

yeoldebrewer

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For you cheapos like me out there. I have one of these, and I can pretty much calibrate everything else from it.
I take it from reading another page on the company's web site that this is a red alcohol rather than a mercury thermometer? I wouldn't wanna trade one kind of paranoia for another.

Looks like a cost effective (read cheap :) ) solution to the calibration problem.
 

dontman

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The worst part is the drift on thermometers. One week it is perfect and you get complacent and then at some point you realize to your own horror that it has drifted 8 degrees out of calibration.

Yeolde, you would just use the lab thermo to calibrate your other ones. Then you have no worries even if it is done with mercury.
 

antsp1

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I take it from reading another page on the company's web site that this is a red alcohol rather than a mercury thermometer? I wouldn't wanna trade one kind of paranoia for another.
Yes, they are the red alcohol ones. I got the one with the yellow back for better contrast. I have used it for about 4 years, and it has always been dead on. I check it with a NIST certed Fluke Thermocouple.

Ant
 

RCCOLA

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I take it from reading another page on the company's web site that this is a red alcohol rather than a mercury thermometer? I wouldn't wanna trade one kind of paranoia for another.

Looks like a cost effective (read cheap :) ) solution to the calibration problem.
Just bought one of the 12'' lab thermometers and the packaging reads.This instrument contains one or more of the following.Kerosene, toluene,pentane with aniline dye.Inhalation of the vapor blah,blah,blah.I thought they were just alcohol filled myself.BTW this did come from my LHBS.
 

snowbum007

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I work for the health dept and brought home my calibrated thermocouple a couple of weeks ago. My floating thermometer was 6 degrees off. I bring home my work thermocouple now when I brew.
 

RunBikeBrew

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I've had the best luck with the floating alcohol thermometers (ordered from AHS). I've calibrated them with boiling and ice water. One reads 3F high and one reads 2F high, but they are consistent and the calibration is constant from 32F to boiling. I now trust them (but have to constantly perform the oh-so-complicated mental math of subtracting 2 or 3 from the reading).

I had a digital probe thermometer (with wire) that I have abandonded - completely unpredictable. The only downside of the floating thermometers is that they're not instant-read. They take a couple of minutes, but I don't really do anything that requires and instant response. (Of course, they're also breakable, and I've broken one before, but I try to be careful now.)

(Also, I've found that my fermometer is pretty darn accurate - usually within 1F of my floating thermometer.)

(Also, also, it's hard to get a calibration at 32F. You have to use crushed ice, very little water, insulated cup, and stir...)
 

SpanishCastleAle

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I just did a brew where my POS dial thermometer (the ones about 10" long) ended up way off and a brand new digital probe thermometer ended up 10o F too high. Both were good at the beginning of the brew. No more using that POS dial thermometer.

Then theres ole reliable...the little dial thermometer in the little red holder (so you can put it in your pocket like a ballpoint pen)...that thing is like 20 years old and just keeps on ticking...accurately. It's just too short.

FWIW, I'm pretty sure the problem with the probe thermometer was that wort/water got inside the probe. It was def the probe and not the electronic part that went bad. I guess these things are not meant to be submersed. Oh well...the replacement will be relegated to keezer/refrigerlager/swamp patrol.
 
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