Thermometer Trouble

[scurry64]

I am using a battery operated probe thermometer like the one pictured below and I think I have been having problems with it. I didn't realize it until I was chilling my Premium American Lager wort last weekend.

The thermometer reading stuck at 85 f and I knew that couldn't be right. So, I grabbed my old thermometer that came with the kit I got 6 years ago, sanitized it, and stuck in the wort. It read 58 f. I panicked because if it was telling me that my 58 f wort was 85 f, what was the real temperature of my 152 f mash? Yikes.

I suppose it could be battery related, but I just replaced the batteries the week before. I know. I know. There is no guarantee the batteries I brought home from the store were fresh.

I haven't tested it in ice water yet, but I will do so when I get home. My question is this: What type of thermometer do you use? What works best for you?

 

[zachattack]

Thermapen... the last thermometer you'll buy. Use it for brewing, baking, grilling, roasting, etc.

 

[mjohnson]

Thermapen... the last thermometer you'll buy. Use it for brewing, baking, grilling, roasting, etc.

They are expensive - but worth it. I use it daily. It is so nice to have at least 1 thermometer that you can trust to be accurate. Then you can get the cheapo's and know how they stack up.

 

[zachattack]

They are expensive - but worth it. I use it daily. It is so nice to have at least 1 thermometer that you can trust to be accurate. Then you can get the cheapo's and know how they stack up.

So much less stress when you know you can trust a thermometer.

 

[Dougie63]

Get a non digital candy type thermometer you cannot calibrate them because they are sealed and do not need calibration

 

[zachattack]

Get a non digital candy type thermometer you cannot calibrate them because they are sealed and do not need calibration

I have a sealed thermometer that does need calibration, and I can't calibrate it...

 

[mux]

+1 thermapen

 

[Dougie63]

I have a sealed thermometer that does need calibration, and I can't calibrate it...

what are you comparing it to? if its the glass merc/alc type they are accurate and dont need calibrating

 

[zachattack]

what are you comparing it to? if its the glass merc/alc type they are accurate and dont need calibrating

I'm comparing it to the freezing point of water and the boiling point of water.

In theory they're accurate, but nothing's perfect. Especially if yours is a cheaper one (ex. the sealed alcohol thermometer that comes in the NB starter kit) you should check it, you'll be surprised.

Just because you can't calibrate it doesn't mean it's 100% accurate, that's like saying a light bulb that you can't reach will never need to be changed.

 

[G_Brew]

I have 6 thermometers... including the nice one on my kettle to a few probe types like yours and some 12 inch long stem ones... I've conducted several tests at boiling, I've calibrated and/or figured out the exact difference between each thermometer relative to each other... so if my main one dies, I can finish the brew day without it....

but i do like what everyone is saying about this thermapen.. I may have to get one of those...

 

[Dougie63]

are you boiling water thats distilled? what is your altitude you need to take these in account also

 

[zachattack]

are you boiling water thats distilled? what is your altitude you need to take these in account also

I live at the top of Mount Everest but I brew in Death Valley, and I was checking it in boiling sea water. That's how you do it, right?

I know how to properly calibrate a thermometer. Mine is off, and I've seen it in other glass thermometers as well. I'm not saying yours needs calibration, but if you haven't checked it I would. If you assume everything works as advertised, you're gonna have a bad time.

I still check my Thermapen for calibration, but I've never needed to adjust it.

Here's the crappy one that came with my starter kit:
http://www.northernbrewer.com/shop/review/product/list/id/278/category/70/

 

[jhoyda]

I use a thermocouple plugged in to my trusty Fluke 179.

 

[afr0byte]

I am using a battery operated probe thermometer like the one pictured below and I think I have been having problems with it. I didn't realize it until I was chilling my Premium American Lager wort last weekend.

The thermometer reading stuck at 85 f and I knew that couldn't be right. So, I grabbed my old thermometer that came with the kit I got 6 years ago, sanitized it, and stuck in the wort. It read 58 f. I panicked because if it was telling me that my 58 f wort was 85 f, what was the real temperature of my 152 f mash? Yikes.

I suppose it could be battery related, but I just replaced the batteries the week before. I know. I know. There is no guarantee the batteries I brought home from the store were fresh.

I haven't tested it in ice water yet, but I will do so when I get home. My question is this: What type of thermometer do you use? What works best for you?

I have the same (or very similar set). I got a new thermometer since these seemed to fluctuate/get stuck. Also the remote thermometer on mine reads high. Perhaps water got where it wasn't supposed to on mine?

 

[Dougie63]

I live at the top of Mount Everest but I brew in Death Valley, and I was checking it in boiling sea water. That's how you do it, right?

I know how to properly calibrate a thermometer. Mine is off, and I've seen it in other glass thermometers as well. I'm not saying yours needs calibration, but if you haven't checked it I would. If you assume everything works as advertised, you're gonna have a bad time.

I still check my Thermapen for calibration, but I've never needed to adjust it.

Here's the crappy one that came with my starter kit:
http://www.northernbrewer.com/shop/review/product/list/id/278/category/70/

Mine is perfect fyi I work in the food industry inspections div and part of my duties are calibrating thermometers I have found that glass thermometers that are NSF cert are spot on, its the digitals and dial face that require constant calibration due to shock, vibrations ect if you have a "quality" glass thermo not one made in china it will be within -+ 1 deg

 

[Dougie63]

I have the same (or very similar set). I got a new thermometer since these seemed to fluctuate/get stuck. Also the remote thermometer on mine reads high. Perhaps water got where it wasn't supposed to on mine?

if you get some heat shrink tubing and put it on the probe where the wire goes in it will last much longer

 

[zachattack]

Mine is perfect fyi I work in the food industry inspections div and part of my duties are calibrating thermometers I have found that glass thermometers that are NSF cert are spot on, its the digitals and dial face that require constant calibration due to shock, vibrations ect if you have a "quality" glass thermo not one made in china it will be within -+ 1 deg

Copy that. All my experience has been with cheapo ones

 

[mjohnson]

I also think that consistency is more important than accuracy. Once you get to know your process/system, you can adjust based on your results and get repeatable beers. Brew a beer, if its a bit thin, mash higher next time. When its dialed into what you like, just remember that temp.

 

[william_shakes_beer]

I am using a battery operated probe thermometer like the one pictured below and I think I have been having problems with it. I didn't realize it until I was chilling my Premium American Lager wort last weekend.

The thermometer reading stuck at 85 f and I knew that couldn't be right. So, I grabbed my old thermometer that came with the kit I got 6 years ago, sanitized it, and stuck in the wort. It read 58 f. I panicked because if it was telling me that my 58 f wort was 85 f, what was the real temperature of my 152 f mash? Yikes.

I suppose it could be battery related, but I just replaced the batteries the week before. I know. I know. There is no guarantee the batteries I brought home from the store were fresh.

I haven't tested it in ice water yet, but I will do so when I get home. My question is this: What type of thermometer do you use? What works best for you?

The probes in your picture are steel braids intended for oven use, not immersion. Check out Bobby M's tutorial on waterproofing it for immersion use. I have a thermapen digital oven thermometer that I did, works fine. The only thing I did differently was seal the silicone tubing at the business end with heat shrink instead of triple o rings.