I brewed a Smashing Pumpkin Ale yesterday and used 2# 6 Row and 3 cans pumpkin. Before I heated the strike water, I tested three thermometers in different temperatures of water. The three thermometers were: 1 Standard homebrewing floater, 2 CDN Self Calibrating Digital, 3 A mercury glass type I got from Williams Brewing that was sold to be used for calibrating other thermometers (High Dollar SOB). Here are the results at different temps: In ice water calibration-29.5, floating-32, digital-32. In strike water calibration-155, floating-170, digital-154.7 In mash, Calibration-155, floating-170, digital-154.7. Obviously there is something amiss here. If I am ever going to be successful at AG I will need an accurate thermometer. Any suggestions? Thanks
Thanks. I had seen these posted but couldn’t remember the name.
Bummer that your high dollar thermometer doesn’t seem to match reality. Did it come with calibration data, and is it deviating from that? Most specs are written as percentage deviation proportional to offset from room temperature. So it might be dead nuts on at room temperature even if it is a little off at extremes.
Here is a post on my blog about this very issue:http://woodlandbrew.blogspot.com/2012/1 ... eters.html
Woodland, the calibration thermometer is about 15" long and it’s package says "Thermometer ASTM15F 30/180F. On the thermometer itself it says "KESSLER USA 4777 75 TOTAL IMM ASTM15F-86. Could this mean it needs to be totally immersed? I’ll Google it.
I’m confused 1tun. From your numbers, it looks like the premium “calibration” and and the digital thermometer match well within the standard errors that are expected for those guys, and the floater is the outlier. Is there a reason/evidence to believe the floater is giving the “true” (most accurate) result?
I think the floater is worthless and from what I can tell by Googleing Kessler’s site is that the calibration thermometer needs to be completely immersed to be accurate. I plan to call them Monday and ask. If it does, I plan to immerse it in water in a wallpaper tray as close to 150F as I can and then compensate my digital to correct it. The floater goes in the trash. Next I want a thermopen.
$90 for a thermometer??? No thanks.
Yep. That’s how my calibration thermo works.
I used to say that, but then I finally splurged on a Thermopen. I’ve messed with multiple thermometers, but nothing has been as easy to use, and I love how fast it registers the temp. They have sales every now and then at $79. Watch this forum, as people usually post about it when they do.
I knew there had to at least one. :lol:
They just had a $74 sale on brown ones. I usually always post the sales but didn’t get that one in.
I know the Thermapen gets all the love around here, but this is a much better buy if you’re going to spend the money: http://thermoworks.com/products/handheld/therma_k.html
It’s just as accurate and fast as the Thermapen with the included probe, but a lot more versatile. You can get an endless array of other probes if needed for other purposes. I use the waterproof 113-372-T probe to monitor my mash temps.
I dunno, I found with certain things that I use a lot, like flashlights, brewing/meat thermometers, binoculars, you can spend a ton of money over a number of years and end up with a drawer full of junk, or spend it upfront and have something reliable. Thus, I own a surefire flashlight, a thermapen, and Swarovsky binos. When I tell people how much I paid for them, they cringe/laugh in my face. But then again I have $hit that works…really works…and if it doesn’t I send it back and they send me a new one.
Before getting my thermapen, I spent probably the equivalent of what it cost me on floaters, lab thermometers, probes, not to mention a ton of swear words, blood pressure raises and screwy mashes.
Most liquid-in-a-glass-bulb type thermometers have an “immerse to” line silk screened onto them. I haven’t seen the model you got for calibration, but most lab thermometer need to be at least 10 or 15 cm immersed to eliminate stem effect. Total immersion would totally eliminate the error, but if you did that I’m not sure how you’d then read your mash temp :?
Oh yeah, love my thermapen
Another thing to note about the ASTM 15F is that it is for temperatures from 30-180 degrees F, so you can expect that it will not be as accurate at freezing.
I think the floater is worthless and from what I can tell by Googleing Kessler’s site is that the calibration thermometer needs to be completely immersed to be accurate. I plan to call them Monday and ask. If it does, I plan to immerse it in water in a wallpaper tray as close to 150F as I can and then compensate my digital to correct it. The floater goes in the trash. Next I want a thermopen.[/quote]
If we agree that the floater is worthless, my take-away is that the calibration therm and the digital are about as dead-on as you can expect, with the possible exception of freezing temp. As mentioned above, correlation at 32F should not be expected to be perfect under the circumstances, and more importantly it’s probably a total don’t-care as long as it matches well at mash temps.
The only thing that gives me pause here is that depending on your actual immersion depth, a full immersion calibration therm can be substantially off if not used as intended. So this makes me wonder a bit if your apparent close correlation at some temps is real.
Just out of curiosity, how deeply immersed was the calibration therm when you compared?
[quoteJust out of curiosity, how deeply immersed was the calibration therm when you compared?
][/quote] Not near deep enough.