Thermapen...

[motobrewer]

Tim, I would like to know what is the difference between the device everybody here is mentioning (thermapen) and this one:

http://thermoworks.com/products/low_cost/rt610b_12+24.html

I really like this one because of the probe length, but I suppose it's not as accurate as thermapen....

thanks

p.s.

question is not only to Tim, but to anyone who knows the answer

Low-cost:
Response Approximately 15 to 20 seconds in liquid
Accuracy ±1.8°F / 1.0°C over full range

Thermapen:
Speed From 75°F to 32°F: ≤ 3 seconds to within 1°F
Accuracy ±0.72°F (±0.4°C) from -58 to 392°F (-49.9 to 199.9°C), ±1.8°F (±1.0°C) from 392 to 572°F (200 to 299.9°C)

±1.8°F is not something I'd want to use to take a mash reading.

 

[400d]

Low-cost:
Response Approximately 15 to 20 seconds in liquid
Accuracy ±1.8°F / 1.0°C over full range

Thermapen:
Speed From 75°F to 32°F: ≤ 3 seconds to within 1°F
Accuracy ±0.72°F (±0.4°C) from -58 to 392°F (-49.9 to 199.9°C), ±1.8°F (±1.0°C) from 392 to 572°F (200 to 299.9°C)

±1.8°F is not something I'd want to use to take a mash reading.

I know, but the long probe is very important, at least for me, because I just put it into the mash through a little hole on the lid of my converted mash tun, and I can check the temperature without opening the lid....

anyway, i definitely consider buying this...

 

[motobrewer]

well, that's fine, but just know that when it says 154, it could really be 156.

 

[400d]

well, that's fine, but just know that when it says 154, it could really be 156.

opening the lid three times to take a reading with thermapen could make 156 drop to 154

ok, I'm only half serious....

If only there was a thermapen with longer probe....

 

[motobrewer]

or keeping the lid open while the lower cost one takes 20 seconds to take a reading, lol.

i'm really not trying to bash the lower cost one, it seems like a decent unit, but for me it's a bit innacurate and slow.

i understand your desire for a long probe, I used to mash in a rubbermaid, but if you stir well, the temperature will be evenly distributed.. I mean, it's not a block of iron, it's water, heat moves quickly in water.

 

[broadbill]

well, that's fine, but just know that when it says 154, it could really be 156.

...and could you tell that your favorite beer was mashed at 154 vs. 156?

I don't think I could.

I'm all for getting the best instrument/tool for getting the job done (and this is why I've asked Santa for a Thermapen), but I would argue that at the end of the day you will get identical results with the lower cost thermometer.

 

[motobrewer]

...and could you tell that your favorite beer was mashed at 154 vs. 156?

yes, when it finishes at 1.022 instead of 1.016

https://www.homebrewtalk.com/f163/bad-yeast-just-unfermentable-wort-211897/#post2479421

https://www.homebrewtalk.com/f163/ipa-fg-1-026-stout-fg-1-022-what-do-212984/

 

[Catt22]

i understand your desire for a long probe, I used to mash in a rubbermaid, but if you stir well, the temperature will be evenly distributed.. I mean, it's not a block of iron, it's water, heat moves quickly in water.

IMO, the short probe on the Thermapen is a major shortfall and a deal killer for me and especially so at their current price. It's unlikely that the grain bed temperature will be uniform regardless of how much it's stirred. OTOH, if you only have a thermometer with a short probe, you may never detect the difference. FYI, the thermal conductivity of iron is much greater than that of water. Much greater.

I have a Quick Read CDN like this one that has a response time of 6-8 seconds which is not bad at all:

http://www.amazon.com/dp/B0021AEAG2/?tag=skimlinks_replacement-20

The CDN checks out just fine against a traceable glass lab thermometer that I use as my calibration benchmark.

 

[motobrewer]

yes, you're right, iron conducts heat much better than water. my point was that water can be more thermally homogeneous, especially if you're constantly stirring.

I don't see how it's unlikely that the grain bed temp will not be uniform. i now mash in a square cooler and haven't any "hot spots"

 

[wildwest450]

I have a Quick Read CDN like this one that has a response time of 6-8 seconds which is not bad at all:

http://www.amazon.com/dp/B0021AEAG2/?tag=skimlinks_replacement-20

The CDN checks out just fine against a traceable glass lab thermometer that I use as my calibration benchmark.

Those used to be my go to thermometers, not anymore. You'd better check them every time you brew, which is ridiculous to have to do imo. My last one went off 2+ degrees just like that. Unacceptable to me.

 

[broadbill]

yes, when it finishes at 1.022 instead of 1.016

https://www.homebrewtalk.com/f163/bad-yeast-just-unfermentable-wort-211897/#post2479421

https://www.homebrewtalk.com/f163/ipa-fg-1-026-stout-fg-1-022-what-do-212984/

http://braukaiser.com/wiki/index.ph...ity_and_efficiency_in_single_infusion_mashing

Scroll down to Figure 10 (Effect of mash temp on attenuation)

Quote: "This means that increasing the temperature by one degree Celsius (1.8 F) will lower the limit of attenuation by 4%."

Your example cites is a 27% change in attenuation by increasing the mash temp 2 degrees. Quite a difference from 4% in Kaiser's controlled experiments.

Furthermore, a mash temp of 154-156 is right at the peak limit of attenuation. Being at the peak means that you won't have proportional changes in attenuation (y) with a change in mash temp (x).

 

[Catt22]

Those used to be my go to thermometers, not anymore. You'd better check them every time you brew, which is ridiculous to have to do imo. My last one went off 2+ degrees just like that. Unacceptable to me.

I do check mine regularly and it's been very reliably accurate so far. I think it would be foolish to blindly trust any thermometer, including the glorious Thermapen. I like the user calibration feature the CDN has. A very high price does not necessarily guarantee very high accuracy.

 

[wildwest450]

I do check mine regularly and it's been very reliably accurate so far. I think it would be foolish to blindly trust any thermometer, including the glorious Thermapen. I like the user calibration feature the CDN has. A very high price does not necessarily guarantee very high accuracy.

Sarcasm noted. I calibrated my CDN, it's still 2+ degrees off where it counts, in the 150f to 160f range. So that feature is worthless.

 

[Catt22]

Sarcasm noted. I calibrated my CDN, it's still 2+ degrees off where it counts, in the 150f to 160f range. So that feature is worthless.

My pont was that no instrument is immune from defects, including the Thermapen. I do have more faith in my traceable glass lab thermometer than any other though and that's what I use to calibrate the others. I only use the CDN for cooking and other miscellaneous tasks. I have a Cole-Parmer traceable digital thermocouple thermometer that I use in the mash tun. It's proven to be very accurate and reliable and I can place the probe deep in the grain bed where it counts.

 

[SpanishCastleAle]

When my digital meat thermometer probes got wet they went off by almost exactly 2 degrees (had it happen twice). Baked the probe in the oven and it came back to spec (I check it at work at mash-temp vs. regular mercury-filled thermometers with verified accuracy). I don't know how warm that unit can get but maybe something to consider (drying it out somehow).

I'm still just using Taylor digital meat thermometers with heat-shrink tubing on the metal-wire interface. I try not to submerge it and it's been fine for the last ~50 brews or so.

 

[TheAleMaster]

I'm still just using Taylor digital meat thermometers with heat-shrink tubing on the metal-wire interface. I try not to submerge it and it's been fine for the last ~50 brews or so.

You're lucky. I've already gone through 2 Taylors. Both lasted maybe 10 brew sessions. After the last, I decided to order a Thermapen. It came but I have not yet brewed with it. Excited to do so!

 

[SpanishCastleAle]

You're lucky. I've already gone through 2 Taylors. Both lasted maybe 10 brew sessions. After the last, I decided to order a Thermapen. It came but I have not yet brewed with it. Excited to do so!

How did they fail? I have three of them. One is 'stock' and is always in the keezer. One I removed the stainless steel probe (after it got wet several times) and just stick the thermocouple junction into a thermowell in a carboy. The other one has the heat shrink tubing on the probe. I use them not only to brew but also to monitor fermentation temps, lagerator temps, and for cooking. All 3 still work even though I partially melted the main housing on the one with the heat shrink tubing on it. Dropped them several times.

I actually want a Thermapen but I'm waiting for one of these to fail first. Maybe that's the trick, you have to WANT it to fail.

 

[TimothyRobinson]

see below

 

[TimothyRobinson]

Tim, I would like to know what is the difference between the device everybody here is mentioning (thermapen) and this one:

http://thermoworks.com/products/low_cost/rt610b_12+24.html

I really like this one because of the probe length, but I suppose it's not as accurate as thermapen....

thanks

p.s.

question is not only to Tim, but to anyone who knows the answer

There are many differences, of course. The main ones being the speed and range. The Thermapen gives accurate readings in 3 seconds or less (often less) while the thermometer you've linked to (RT610B) takes about 15 seconds. That's because it has a thermistor sensor and because of the size of the probe. The Thermapen has a micro-thermocouple sensor and a reduced tip. The thermocouple allows the Thermapen to go from -52°F to 572°F as well, where as the long-stem goes from -58°F to 392°F. It is more for composting and other environmental uses. Incidentally, we have some other thermistor-based digitals (less expensive) that are accurate in 5-6 seconds, see here: http://thermoworks.com/products/low_cost/rt301wa.html and here: http://thermoworks.com/products/low_cost/rt600c.html (though they top out at 302°F).

 

[motobrewer]

so, i got one for christmas...

we were in the kitchen, my dad took his taylor thermometer and put it in the pot of boiling water. it read 212.5F I put mine in, it read 210F. so obviously, I got crap for it...

looked up the current air pressure ,it was 29.40 inHg. Solving the ideal gas law gave 210F for boiling water.

brought it home, but the thermapen and my taylor into an ice bath. probes were right next to each other in the middle. taylor read 34.F thermapen 32.0F

 

[ruffdeezy]

Just ordered mine with christmas money. Can't wait to start using it for brewing and grilling. Got a yellow one.

 

[TimothyRobinson]

That sounds about right. Glad you're enjoying your Thermapen! For a quick way to figure the boiling temp where you live, see http://www.thermoworks.com/BoilingPointCalculator

 

[wildwest450]

There are many differences, of course. The main ones being the speed and range. The Thermapen gives accurate readings in 3 seconds or less (often less)

Although I love my thermapen, I have to call bravo sierra on this. I have been taking temps on everything since I got mine 2 weeks ago, it's not that fast. 5-6 seconds is a lot closer than 3. And I do realize they never really settle, but i'm talking actual temps still dropping/rising. Is mine defective, or are you being a little optimist?

 

[motobrewer]

thermodynamics plays a bit into this. i mean, if you had a glass of water at a stable temperature and you shoved the pen into it, it'll get to that temp pretty quickly.


but if, for instance, you put it between your fingers until it heated up, then took your fingers off, it's not going to come back to room temp within 3 seconds. first, you built some heat into the metal probe, and second, non-moving air isn't very effective at moving heat.

 

[Catt22]

Although I love my thermapen, I have to call bravo sierra on this. I have been taking temps on everything since I got mine 2 weeks ago, it's not that fast. 5-6 seconds is a lot closer than 3. And I do realize they never really settle, but i'm talking actual temps still dropping/rising. Is mine defective, or are you being a little optimist?

It's always refreshing to read a truly unbiased report. FWIW, I bought a cheap digital thermometer at Wally World for use when heating water to make French Press coffee. The cheapy was only $9.99, has a replaceable battery and a user accessible calibration screw. I checked it against my traceable glass lab thermometer and they agreed within a tenth of a degree. Not saying that they will all be this well calibrated, but this one happened to be. The instructions claim a response time of 5-10 seconds and that jives with my testing. I gave it to a friend along with the French press as a Christmas present. I think I will pick up another to have around as a backup and for use in the kitchen maybe. At that price, they are practically disposable. I'll post a pic if I buy another.

 

[Catt22]

thermodynamics plays a bit into this. i mean, if you had a glass of water at a stable temperature and you shoved the pen into it, it'll get to that temp pretty quickly.


but if, for instance, you put it between your fingers until it heated up, then took your fingers off, it's not going to come back to room temp within 3 seconds. first, you built some heat into the metal probe, and second, non-moving air isn't very effective at moving heat.

Agreed. It also depends on how much difference there is between the temperature of the probe (room temp?) and the temperature of whatever it is you are trying to measure. It will take longer to get from say 70F to 150F than it will from something like 70F to 100F. At least this is what I have observed with every thermometer I've ever used regardless of what kind it is. Some are faster than others, but none are truly "instant" IMO. With the "type k" thermocouple thermometers, you can buy replacement probes that have a faster response time. I use the plain wire bare junction type and they are plenty fast for my application.

 

[motobrewer]

indeed. i'm not terribly worried about speed, mainly accuracy.

 

[wildwest450]

indeed. i'm not terribly worried about speed, mainly accuracy.

Me neither, but it's a claim they made. It was a simple air temp (68f) to water glass temp(40), I checked it first to get a temp, let it go back to room temp then timed it.

It took 6+ seconds, not very impressive.

 

[motobrewer]

6 seconds to what, final destination? the claim is 3 seconds to within 1 degree F. i'm not trying to defend them, and I haven't done any time trials myself, but it seemed quick when I was testing random stuff.

 

[Sawdustguy]

Although I love my thermapen, I have to call bravo sierra on this. I have been taking temps on everything since I got mine 2 weeks ago, it's not that fast. 5-6 seconds is a lot closer than 3. And I do realize they never really settle, but i'm talking actual temps still dropping/rising. Is mine defective, or are you being a little optimist?

I would call them if it is not doing what they claim it will do. I have a thermapen also and never really checked how much time it took. It was always fast enough for me but now I think I will give it a test just for chits and giggles.