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boogiesnap
10-30-2011, 10:35 AM
hi guys, i know they're impeccably accurate and lightning fast, but not so sure about mine.

it is supposed to have an accurate reading in like 3 seconds, yes?

but when i open mine it takes a good 10-14 seconds to settle on a temp.
or if i put it in my oven(i'm proofing some starter culture, pizza baby, pizza), it does the same thing.

honestly, are yours truly this "fast" or is mine malfunctioning?

thanks!

Smokeadelic
10-30-2011, 10:52 AM
Sounds like yours is on the fritz.

Midnight Smoke
10-30-2011, 10:54 AM
Mine is fast, maybe call the Mfg and ask them. I have heard they are great to work with in customer service.

Gore
10-30-2011, 11:05 AM
Any thermometer will take time to come to equilibrium and give you an accurate temperature reading. This time depends on a number of factors. Two of the most important are the thermal mass of the thermometer (the tip) and that of the surrounding medium. To get an accurate reading, the thermometer tip must come up to the temperature of the surrounding medium. It makes sense that this be thin, and you will see most quick thermometers have a tapered tip (Of course if it is too thin, then you risk breakage). The second factor is the surrounding medium you are measuring. That medium has to transfer its heat to the thermometer, thus reducing its temperature and be heated up again by its surroundings. This all takes time. Some media transfer energy faster than others and some store more energy than others. If you are measuring air, you will have a much different response time than if you are measuring water. If your probe is already hot, you will have a much different response time than if it is cold. This is one reason there are so many ranges of response time. It sounds to me like you are measuring air. This will take a long time for any thermometer to measure. I think about the best method to determine response time (and something everyone can do) is to have a pot of boiling water. With the thermometer turned on and at room temperature, put the probe into the water and measure the time it takes for it to read approximately 212*. It should be approximately 4-5 seconds for the Thermapen. I would do this test before you do anything else.

Will32Rod
10-30-2011, 11:41 AM
Just a thought, battery may be starting to die.

Sledneck
10-30-2011, 12:14 PM
What color is it?

BGEMike
10-30-2011, 01:27 PM
I hope it's not brown I just ordered one.

bam
10-30-2011, 02:55 PM
Get a blue one or check battery.

Dave Russell
10-30-2011, 03:25 PM
It might be defective, but I believe Gore is right and I'd always start with a boiling water test. One thing I've learned is not to probe steaks while they're still on the grate.

Ron_L
10-30-2011, 04:43 PM
The Thermapen isn't designed to measure air temp, so if you are just opening it without sticking it ingo a piece of meat I can see where it would take a few seconds. If you look at the Maverick ET-73 or 732 the meat probe and the meat probe and the pit probe are two different designs. One is designed to measure meat temp and the other air temp.

boogiesnap
10-30-2011, 05:42 PM
thanks everyone.

i'll do the boiling water after the pats game and report.

not sure why measuring air would be different than measuring meat. i would think ambient temp is what it is regardless of medium.

but on the other hand, gore and ron, those answers make sense.

Sledneck
10-30-2011, 05:57 PM
Get a blue one or check battery.

He didn't answer my question so imbedding it's not the lightning fast and way more accurate blue one. Thats his problem in a nut shell. I bet it's one of those defective red ones. Or a red one painted blue

Ron_L
10-30-2011, 05:57 PM
Different types of thermocouples are respond differently depending on the medium. Some are designed for direct contact.

Gore
10-30-2011, 07:05 PM
thanks everyone.

i'll do the boiling water after the pats game and report.

not sure why measuring air would be different than measuring meat. i would think ambient temp is what it is regardless of medium.

but on the other hand, gore and ron, those answers make sense.

Imagine yourself as the thermometer. It is a nice spring day and EVERYTHING is 68*. You are very comfortable inside. The air immediately around your body has been warmed. Now go outside. It is 68*, but there is a strong wind blowing. That air around your body is constantly being cooled by the wind and more of your body heat is going into heating that air. You feel cold because heat is being sucked from your body at a faster rate. Now go into your bathroom. The tub is filled with water from the night before. It also is 68*, but when you get inside, your body immediately registers "Farkin' Cold!" even though it is exactly the same temperature as everything else. That water just sucks the heat from your body.

The point is that it takes different amounts of energy to heat different materials (due to thermal capacity), and it takes different amounts of time (due to thermal conductivity) to do so. Even though all those materials were the same temperature, your body "registered" different comfort levels because of these factors. These factors come into play in the cookware we select and also the cookers that we use and in how fast our thermometers work.

When you put your thermometer into a hot material, heat is transferred to your thermometer from its surroundings and it cools them off. That air doesn't conduct heat very well (we know this from insulating our house), but water, copper and stainless steel does an excellent job (we know this from cooking). Sometimes I will read where people say the got a different temperature reading in different parts of the meat. Part of this is because when you first stick a cold thermometer into the meat, it cools off the meat in order to heat the thermometer. It takes a bit of time for that meat to come up to temperature from the surroundings, but by that time, we've usually taken the thermometer out and put it in someplace else. Low and behold, we have a higher temperature because less heat was transferred to that thermometer because it was already heated, and the response time was MUCH faster. I could probably go on another couple pages, but that is probably more than anyone will read anyway. :icon_blush:

timzcardz
10-31-2011, 07:46 AM
One thing I've learned is not to probe steaks while they're still on the grate.


And why is that?

Oldyote
10-31-2011, 08:46 AM
Imagine yourself as the thermometer.

OK - Done.

I was still pretending to be Guerry but now I'm a thermometer and this is what I'm going to be for Halloween.


Thanks Gore - Great write up. If you do go on for a couple of pages I will read it.

boogiesnap
10-31-2011, 09:40 AM
sooooo, from a cold start out of the drawer and into boiling water it takes about 10 seconds to 212.

folded back up and to room tempreature, back into boiling water about 5 seconds to 212.

i tried this a couple times.

it would seem, the unit needs to "warm up" before being speedy. out of the cabinet it climbs temps slower than after a couple uses in a short time period. starting temps being @ equal.

troytime
10-31-2011, 09:47 AM
what does it read after 3 seconds in boiling water?

boogiesnap
10-31-2011, 10:02 AM
3 seconds it's at like 190* maybe. another couple secs to get to 212. well, 211.6. :becky:

timzcardz
10-31-2011, 10:25 AM
3 seconds it's at like 190* maybe. another couple secs to get to 212. well, 211.6. :becky:


That's not good.

I have an older one and a new splashproof one, and in 3 secs you should be there or at least 209/210.

Westexbbq
10-31-2011, 10:35 AM
It really would help to know what color the thermopen is in order to accurately come up with a definitive diagnosis.
Best guess is that it is one of those sub-par blue ones possibly disguised in a black or orange sheath.

Gore
10-31-2011, 11:01 AM
sooooo, from a cold start out of the drawer and into boiling water it takes about 10 seconds to 212.

folded back up and to room tempreature, back into boiling water about 5 seconds to 212.

i tried this a couple times.

it would seem, the unit needs to "warm up" before being speedy. out of the cabinet it climbs temps slower than after a couple uses in a short time period. starting temps being @ equal.

When you first turn it on, normally it takes 2-3 seconds for the electronics to get settled. This is true for every thermometer. This is also the time that many manufacturers quote as their "response time" however it is a completely useless number. Normally we don't put the thermometer in the meat, let it come up to temp, and then turn the thermometer on -- actually, we never do this, so it is a meaningless value, but manufacturers like this because it is normally a small time (about 2 sec) and makes them look good. It does concern me that your response time is 10 seconds. It does seem a bit long to me. It seems very strange that its speediness increases with time. (Note, I do not have a Thermapen, so I cannot say what is normal for them). Perhaps it does speak for old batteries though.

The most important value is the thermal response time that you measure at about 5 seconds. This is a measure of how we use a thermometer in real life. You take the thermometer out of the drawer, turn it on, wait for it to reach equilibrium (whether knowingly or not), then open you smoker and poke your meat. The time from when you poke the meat and get a stable reading is the most useful number. The "boiling water test" simulates this. When people do this test, they typically get 4-5 seconds (for Thermapens). There is always about a second uncertainty in these from when people start and stop their timing and whether they stop at 210* or 212*. I've never heard anyone report a 3 second response time for this boiling water test with any thermometer. They've always been 4-5 seconds. This value is almost impossible to get out of manufacturers -- believe me, I've talked with people all the way down to techies and they will not give it out. In any case, it seems that your Thermapen is not out of line with others. I don't know if that helps you or not.

Hell Fire Grill
10-31-2011, 11:01 AM
Boogie You should change your signature line so you dont embarrass all the other grey thermapens.