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Quality digital thermometers?

MaltLicker

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Anyone using a high-quality digital thermo like Thermoworks makes?  I saw the Homebrewfinds tip on the (costly) Thermopen, and then saw many other options for $20 to $30.

http://thermoworks.com/products/low_cost/


I have calibrated my $10 Walmart/Target thermos in ice water with no issues, but recently did so at 155F and had too-wide variances to feel comfortable with any of them. 

I'm interested in the ones with accuracy +/- 1.0F.    I figure I could at least trust that for calibrating the others I already have as well. 
 
I also use a cheap walmart digital.  I tested it at freezing and boiling, adjusting for altitude, and it was right on.  I wonder if mine is off at fermentation temperatures too?
 
I gotta imagine some of the expense of the thermopen is how fast it is. Its display is also very large. It is also waterproof or splash proof.

I don't use any other, but I imagine most thermometers have very repeatable results even if they are wrong by a specific amount


Have you seen the calibration video on thermoworks website? You might reconsider your calibration after watching it.

How did you calibrate 155? You just stuck the thermometer in the same glass of hot water over and over and got different results each time?
 
I use the "Therma K Plus"  from Thermoworks - very happy with it. 

It is a hand held commercial quality unit for which you can buy a whole range of plug in "Type K" thermocouple probes - some are hand held probed (great for the BBQ too) others are just wire probes available in different lengths - I use those to just drop into the HLT / MT or BK.

It wasn't cheap, but works perfectly and seems very rugged.  The probes respond very quickly.    I bought it as an over reaction after having problems with a couple of cheap digital ones!  Don't regret it though and would buy again.

It comes with a calibration certificate and from memory is claimed accurate to about half a degree.

I bought an optional soft silicon boot that fits over the hand held unit.



Brian
 
 
Is there a specific reason to go digital vs. analog? Is it about speed, or about a display you can actually read without having to grab the readers?

All of mine are analog but admittedly; I calibrate my hand-held through the entire range (in 10 F increments) with one of our digital meters from work - they all have traceable calibration - so I know I'm spot-on with that one, then I'll calibrate my others (Brewmometers installed in the HLT and BK) to that first one. Simple turn of a screw and they're calibrated.

Granted my hand-held is a commercial lab-grade unit on a 12" stainless probe but it still doesn't approach the cost of a comparable digital unit. I'm not a cheapskate by any stretch, but I'd love to hear if having at least one "good" digital in the arsenal is worth the investment.
 
grathan said:
How did you calibrate 155? You just stuck the thermometer in the same glass of hot water over and over and got different results each time?

I have one of those $6 glass thermos, and it is accurate at 32F and 212F, so I have been assuming it was also accurate in the 150's range.  Until I tested them all in the same cup of water.  The glass one seemed lower than the other two digitals, which were also apart from each other. 

SUPER-FAST® POCKET THERMOMETER - REDUCED TIP
Model: RT600C

I am more interested in accuracy than speed, and then water resistance over ability to calibrate, so this one would be the one I'd try.  If you take care of these things, are they likely to stay accurate as when produced and tested? 


 
This just in......SUPER-FAST® POCKET THERMOMETER - REDUCED TIP Model: RT600C

I arranged a group-buy with friends and got them for $15 and cheap shipping. 

This is hardly scientific testing, but I tested them all in crushed, slushy ice water, and the RT600 went quickly to 32.0F in maybe six or eight jumps and then held steady.  Interestingly, the two cheap AccuRites have different model numbers on the face, and the more accurate one is deadly slow, as in single-digit movements, like time passing on a clock.  The 2-3F difference in the two AccuRites was present at freezing as well. 

The yellow one is accurate at 32.0F but almost ten degrees low at 150F.  The other glass one is a prize I won and forgot I owned.  It's slow but more accurate in the 150F range. 

As the water cooled, the digitals were much more responsive to the drop, compared to the glass ones. 

I have no idea which AccuRite I was using, but 50-50 it was the faster one, which is 2-4F off, meaning I was mashing higher than I thought.  Certainly would explain why my kolsch mashed at 150F was not crisp at all. 




 
Just wrapped up this APA today.  Tested the new thermometer in an actual mash and sure enough, the old POS was three-plus degrees F low.  So I've been mashing higher than intended on every batch for a while. 


 
MaltLicker said:
Just wrapped up this APA today.  Tested the new thermometer in an actual mash and sure enough, the old POS was three-plus degrees F low.  So I've been mashing higher than intended on every batch for a while.

I have been testing all of my equipment lately.  Thermometers, refractometers, PH meters, hydrometers etc.  I believe at least a yearly check is worthwhile.
 
Sorry this is slightly off topic - but I think related ...........

Something I have noticed with pretty much  every mash I have done is that my mashes always have very definite hot and cold spots. 

As mentioned earlier in this thread,  i use a pretty accurate commercial grade thermocouple type thermometer and  find that even through I try to initially stir  the grain in very thoroughly  to break up any dough balls,  using  a substantial sized mash paddle,  and I stir it again once or twice during the mashing process, I can still move the probe around towards the end of the 60 minute mash and find a variation of almost as much as ten degrees in different areas of the MT.

It is a bit disconcerting when I am trying to shoot for a mash temperature accurate to a degree or two!   

About all I can do is to move the probe around and try to judge the average temperature and then make any mash adjustments accordingly.

Anyone else find this?  If so, have any thoughts on what to do about it?  I guess I could stir more often, but I don't like opening the igloo cooler too much during the mash.

Brian.
 
I would find this only if I didn't stir at all. 10 degrees is a lot after 60 minutes. I stir aggressively for maybe 2 minutes and then that is it.

You put the grain or the water in first?
 
grathan said:
I would find this only if I didn't stir at all. 10 degrees is a lot after 60 minutes. I stir aggressively for maybe 2 minutes and then that is it.

You put the grain or the water in first?


I use Beersmith to tell me the water temp required to compensate for temperature reduction by the the grain - but not compensating for the cooler. 

Then I heat the strike water to maybe 12-15 degrees above what is needed to compensate for the grain alone,  and pump the required amount of strike water into the MT.   

I then wait until the water temperature drops it falls to the required temp for the grain compensation and add the grain to the water in about four batches, stirring all the time.

Brian.





   
 
Might wanna consider a drill powered mash stirrer.

Something like this:
fa4449dd-465b-4c5d-bf11-c1ec7e831160_300.jpg

www.homedepot.com/p/Workforce-5-Gallon-Helix-Paint-Mixer-HM5HD/202251543#specifications


Or possibly some type of recirculating HERMS or RIMS system. Though honestly I don't think cold/warm spots are gonna matter all that much.
 
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