Thermapen Trust Issues - Wild Temperature Fluctuations.


 

JeffB

TVWBB Pro
I have been using my Thermapen now for several years and have recently stopped trusting it because of wild discrepancies in the indicated temperatures. Before you say to check the battery, there is nothing wrong with the battery I assure you.

For example, I cooked bone-in pork chops the other night and in the oven the temps read around 158*, but when I pulled and read it again as it sat on a plate, it was closer to 141*. Same angle, same chop.

Other times, inserted from above a steak the temp might read 165* but inserted from the side to the same center point the temp may read closer to 138*.

I understand that you are supposed to insert the probe from the side, and the temp you are getting is from the very end of the probe, but why such a large variance from time to time, particularly when you are presumably reading the same center point of the meat, irrespective of whether you come at it from above or from the side?

I do not think I have ever done any damage to my Thermapen by washing in the dishwasher, etc, but I have ignored the instructions that say not to immerse the probe in water to clean it. I mean, when you insert it into meat or other food items, it's getting "wet" from something (meat juices, melted cheese, etc), so I fail to see how rinsing the probe in water and then drying with a paper towel could harm it. The worst I have ever done to it is to let water run on the probe, used a soft brush to remove sticky food and hand dried it with a paper towel.

Thoughts? Comments?
 
have you done the boiling water/ice water test? If it is several years old maybe it is going a little haywire.
 
It's easy to go too far when pushing in from the top with a thin cut of meat. Are you watching how far the probe is going?

What about checking it against another thermometer?
 
I'd say this is mostly a testament to just how sensitive the thermapen is. In a 1" chop or steak there's going to be a huge gradient of temperatures from edge to center to edge. Your hands may not be as precise as you think they are at judging the center of the cut, and the thermapen measures right at the tip of the thermocouple, it doesn't take an average along the skinny part of the probe or anything like that.

For this reason always insert from the side, and check a couple different spots if you're curious.
 
I'm not sure how you can be assured it's not the battery. If you've replaced the battery, it could be junk. I can't tell you how many people at work have trouble with batteries in their fitbits. Though I would agree the other two thoughts expressed in this thread are more likely. First, do the cold water and boiling water test (test it). Second, I agree with the thought that you're just measuring two different places and getting two different but accurate temps. Problem with that theory is that it seems like you would have experienced that after several years of use so back to the first thought - test it and if you can, test the battery.
 
Like mentioned, calibrate per instructions then let us know how much a difference your seeing. Pretty sure their customer service will work with you on getting it right.
 
Reviving this thread because I have lost trust in my Thermapen giving accurate readings.

The first one I got was not a fast read - it would actually take as long as 14 seconds to get a stable reading. I suspected inaccurate readings and did a boiling water test and found that after just 3-4 seconds, it would not stabilize and would continue to climb and then plateau for the peak on average 14 seconds. I got an RMA return for a second unit -and I repeated my test and got much faster results - closer to the claimed 3 sec.

All was good, right?

Well - not so fast.

I also use a Maverick dual probe for continuous readings and noticed another discrepancy with my second Thermapen.

The brisket I did yesterday turned out over done: dry and crumbly.

And I was using the Thermapen for my final temp readings.

Suspecting another issue, I did another constant steady state boil test today and found that the Thermapen was consistently and steadily 4-5 degrees lower than both Maverick probes (which exactly matched).

Not very happy at this point.
 
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When you did the boil test, what did the Thermapen read while in the boiling water ?
Also, what is the boiling temperature of water where you did the test ?
 
When you did the boil test, what did the Thermapen read while in the boiling water ?
Also, what is the boiling temperature of water where you did the test ?

Hi Bob,
I'm at sea level, so 212F is the boiling point.

The Thermapen registered 209F (with momentary peaks to 210 then back to 209).

The Maverick probe registered 214F.

As a check, I have a Weber lollipop digital probe that also registered 214F.

The flame itself on my gas stove goes off the scale, so the bottom of the pan is surely hotter than 212F.
 
I use mine sometimes to measure water temps when baking bread. About a month ago I noticed the water temps would jump as much as 30 degrees while holding probe in water stream, then return to original temp. It would do this sporadically. I replaced the battery and now it's steady as a rock.
 
Interesting results with your Thermapen, Erik. Would be interested in what Thermal Works reply is.
 
I've never been happy with mine. Temperature is never what comes off the grill. I get a better reading from my $9 Betty Crocker thermo that is 20 years old. I've tested it in boiling water and it's quick and accurate but it's very inaccurate with the lower temps of grilled meats.

Kevin
 
I have a Thermapen, Chef Alarm and Thermopop. All work as advertised, quick, easy to use and accurate. Only buy from the Thermoworks website to be sure you are getting the real thing
 
I agree with Dave. I also have Thermopen (one classic and one new style), a Thermopop, and a Chef Alarm. They have never failed me and they all agree on the temps when I use different ones on the same cooks. They also are in agreement with my HeaterMeter probes. The probes I use on the HM are the Thermoworks pro-series. If you are having issues, contact Thermoworks and talk to them. Everytime I have spoken to them, they have been very helpful. Send it in to them and I am sure they will figure out your problem. I won't use any other brand of instant read. Good Luck and let us know what happens when you contact them.

I have a Thermapen, Chef Alarm and Thermopop. All work as advertised, quick, easy to use and accurate. Only buy from the Thermoworks website to be sure you are getting the real thing
 
I've never been happy with mine. Temperature is never what comes off the grill. I get a better reading from my $9 Betty Crocker thermo that is 20 years old. I've tested it in boiling water and it's quick and accurate but it's very inaccurate with the lower temps of grilled meats.

Kevin
Try the ice bath test to test for 32*F. If you're getting accuracy with boiling water and ice water, then it's unlikely the unit is inaccurate, rather it's how you're probing the meat.

Check-out the ThermoWorks Learning Center, specifically the article Getting An Accurate Reading for tips on using the unit.

Good luck!
 
I am a photographer and back in the film days, I learned, in the darkroom, while developing color film that HOW you take the temperature matters, also. When holding the probe in the liquid you are trying to measure, it is important to keep the probe gently moving. As a for instance, the actual temperature of the probe can influence results. The liquid can also set up an insulating layer around the probe which WILL influence the results.

Of course, meat does not require the absolute accurate temperature as color film developing did, but the principle is the same. Just keep the probe gently moving when you are testing it in boiling water or particularly iced water.

Just a thought or two...

As a possible matter of interest, my Thermapen and Thermapop have never failed me. One of these days, after years of use, I expect I'll have to replace the battery:rolleyes:...

Keep on smokin',
Dale53:wsm:
 
Interesting thread. I have two thermopens and they usually read 4 to 5 degrees differently - and not always the same way. Sometimes one is higher and other times the other one is higher. Not sure I would buy another one.
Ray
 
To me, these are the most important comments from Getting An Accurate Reading:

"...a steak or a boneless chicken breast will show differences of many degrees as the tip of the Thermapen probe moves from the surface toward the center of the piece..."

and

"To get a proper reading with the Splash-Proof Thermapen, insert the probe tip into the thickest part of the meat from the top...Slowly push past the center and watch the temperature rise in "real time" at every depth in the piece of meat. Slowly withdraw the probe and watch the temperature change in the opposite direction. If the meat has already been cooked on both sides the very center of the thickest part should have the lowest reading. That is the best place to gauge doneness."
 

 

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