# Which thermometer do I trust? Same temps in water (ice and boiling) but diff temps in stove



## solman (Nov 19, 2018)

I have a Maverick ET732 thermometer I've been using for years without any issues, and recently picked up an Inkbird IBT-4XS. In ice water and boiling water, both units are within a couple degrees of each other. But a strange thing happens when I put them in a toaster oven or smoker (Masterbuilt 40" propane). The Maverick is either higher or lower by as much as 50 degrees compared to the Inkbird. Even after a couple hours, the difference doesn't get any smaller and is persistent. 

Why is it that they're almost the same when testing in water, but so different in actual usage? And how do I determine which one to trust?


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## hillbillyrkstr (Nov 19, 2018)

This is odd.

When you test the thermos in your smoker are they in the exact same spot? Different shelves/sides have different temps. 

I know zero about inkbird products. I can’t help you there. Hopefully someone else can chime in on them. 

I own multiple maverick units and have had great success with them. That being said I’ve replaced probes on them plenty of times in the past. Usually for spiking big time. Are your maverick probes the original ones? If so try ordering another one and testing that one. They don’t last forever. 

All that being said it is odd they are that far apart in the smoker and working properly in boiling water. I still think this is a probe issue and not a thermo issue. 

Good luck,
Scott


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## solman (Nov 19, 2018)

Yes, i tested them in the smoker side by side on the same shelf and mounted on identical but separate probe clips. Maybe the Maverick probe is getting old? They are the original probes I bought back in 2011. Maybe they work as intended when only using the tip, e.g. in water, but lose their accuracy when fully immersed, e.g. in a stove or smoker.


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## bregent (Nov 19, 2018)

Just a wild guess. In your water bath test, heat is exchanged via conduction/convection alone.  In an oven or smoker, there's probably a good deal of radiant energy - so depending on the emissivity/reflectivity of the probe, you might see a different. Are they both clean and shiny? Still, 50F seems like a lot.


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## tropics (Nov 19, 2018)

I would recheck them with boiling water,the toaster may have damaged the probe JMHO
Richie


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## solman (Nov 19, 2018)

that's a good theory, but my meat probe is the cleaner of the two Maverick probes and has the widest temperature difference. the bbq probe that's covered in gunk is about half the gap (15-25F difference compared to the Inkbird).


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## dr k (Nov 19, 2018)

Keep testing. Thermisor vs. Thermocouple could be a difference and the unit. I have different therms that can be 20° off while preheating but pan out.


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## Bearcarver (Nov 19, 2018)

solman said:


> that's a good theory, but my meat probe is the cleaner of the two Maverick probes and has the widest temperature difference. the bbq probe that's covered in gunk is about half the gap (15-25F difference compared to the Inkbird).




I know people say I'm wrong, but I never trust the Meat probe (Bent one) to measure Smoker Temp.

I believe the straight Smoker Probe to be more accurate at measuring "Air Temp".

And like Richie said, I would check with a boiling test, in case the Toaster oven damaged one.

Bear


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## solman (Nov 19, 2018)

The probes are rated for 716F temperature, and in my toaster oven test it never went higher than 400F so the probes shouldn't have been damaged.


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## JckDanls 07 (Nov 19, 2018)

If you get new probes for the Mav. I would suggest getting the hybrid probes that the ET733 uses....And then the probes can be used ether way (food/chamber)  That's a little unusual that you got that many years out of the originals... So congrats on that ...


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## indaswamp (Nov 19, 2018)

What is the response time on the units? If they are different, this could be the issue. A lot of ovens can swing + or - 25 or more degrees. 
I would trust the thermometer with the fastest response time.


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## solman (Nov 19, 2018)

The inkbird is definitely faster. But as i mentioned, the temp difference was persistent over time, so for example in my propane smoker the inkbird would read a steady 239F but the Maverick would be steady 219F for over an hour.


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## indaswamp (Nov 19, 2018)

Did you have the probes right next to each other in your propane smoker?


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## hillbillyrkstr (Nov 19, 2018)

solman said:


> Yes, i tested them in the smoker side by side on the same shelf and mounted on identical but separate probe clips. Maybe the Maverick probe is getting old? They are the original probes I bought back in 2011. Maybe they work as intended when only using the tip, e.g. in water, but lose their accuracy when fully immersed, e.g. in a stove or smoker.



That’s a long time for a probe around here. But I use my smokers a lot more than. The average guy. 

I’d purchase a new probe from
Maverick. You can buy them on amazon. Test that new one out in boiling water and then put it to the test against the other probe/thermo. 

Good luck,
Scott


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## Bearcarver (Nov 20, 2018)

JckDanls 07 said:


> If you get new probes for the Mav. I would suggest getting the hybrid probes that the ET733 uses....And then the probes can be used ether way (food/chamber)  That's a little unusual that you got that many years out of the originals... So congrats on that ...



Hi Jack!!
My first Mav---ET73 still has it's original probes, for 10 years now, but that one spent the last 8 years in my curing fridge.

My second Mav---ET732 had a probe go the second time I cleaned it, because the cable wasn't secured right, I pulled it right out while wiping it clean. I replaced it, and those probes are now 6 years old.

My Third Mav---ET732 is about 3 years old & both are still original, but I only use this one when I need 2 in my smoker at once.

Bear


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## SonnyE (Nov 20, 2018)

Because they are not linear.
If you were comparing two of one, or two of the other, you could hope for close results.
But you are comparing a Ford and a Chevy, or Apples and Oranges.
And as I've said before, these are consumer grade thermometers, not precision, Industrial, or Laboratory, calibrated thermometers.
I tested some 5 different thermometers on my stove. I picked the best one of them as the one I trusted the most.
Water boils at 212° F *at sea level. *So your testing base is flawed from the beginning, unless you live at the beach.


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## solman (Nov 20, 2018)

SonnyE said:


> I tested some 5 different thermometers on my stove. I picked the best one of them as the one I trusted the most.
> Water boils at 212° F *at sea level. *So your testing base is flawed from the beginning, unless you live at the beach.



I live 192' feet above sea level so I'd say it's close enough.

How did you go about testing your 5 thermometers? Ultimately all i care about is how do I know which thermometer to trust.


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## mosparky (Nov 20, 2018)

Only thing I know to do is cook something relatively cheap with one or each. Maybe a pork tenderloin. Cook to 150 IT. If it is still rubbery or really dried out when you cut into it, you know which one not to trust.


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## noboundaries (Nov 20, 2018)

Bearcarver said:


> I know people say I'm wrong, but I never trust the Meat probe (Bent one) to measure Smoker Temp.
> 
> I believe the straight Smoker Probe to be more accurate at measuring "Air Temp".
> 
> ...



Okay, it's not just me. One of the reasons I quit using the meat probe on my 732 was inconsistent temps. Funny thing though, when I hook the meat probe in the chamber plug, it is accurate. That tells me where the problem lies. I use my meat probe for roasting coffee now and leave the chamber probe in the smoker.


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## SonnyE (Nov 20, 2018)

solman said:


> I live 192' feet above sea level so I'd say it's close enough.
> 
> How did you go about testing your 5 thermometers? Ultimately all i care about is how do I know which thermometer to trust.



All players in the same pan.
Iced water to start, then low fire to bring them up to a boil.
Those who couldn't be accurate enough to reach 32°, or boiling (210° at my elevation), got left in the drawer.
One instant read digital, and one analog Industrial, were the closest.
But all were in the same bath.
If you have one therm you can truly trust, use it to test any new ones you get. But don't expect them to run linear.

Since then, I've added a ThermoPro TP-08, and recently an Inkbird IBT 4XS.
So far the new Inkbird has proved out all 4 probes to read the same when soaked in the same heat, same way. (1 grate probe, 3 meat probes.) Which is a good start.
I want to use it to monitor a bacon project I'm in the middle of.

I use to work with very large industrial transformers and electrical equipment. Part of annual testing was to test the temperature monitoring to insure its accuracy, and that it would work when needed to avoid electrical failures, explosions, or fires. So we used laboratory tested and certified thermal wells to make sure the readings were as accurate as possible, and record that they were still performing accurately.
Usually, I would find the equipment was much closer than 2% of full scale it was advertised to be.

So I can accept that our commercially available BBQ probes are often more "Rule of Thumb", and not to expect laboratory accuracies from them, ever.
After all, everything we make is to eat. And we all know what it becomes... :rolleyes:
;)


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## johnmeyer (Nov 21, 2018)

Here's how you can sort this out.

1. Re-do the 32 degree and boiling water tests. You must use distilled water for this, including the ice cubes, if you want perfect results. The 32-degree test should be done with ice from top to bottom of the container, and stirring. The boiling water test needs to be adjusted for altitude if you are more than 1,000 feet above sea level. If you don't use distilled water, and have well water or other water that has lots of minerals, it will change the boiling point. The only reason for re-doing this test is to make sure the two really did agree at those two temperatures. Put both probes in the water at the same time and be sure to stir the water vigorously for at least one minute (especially with the ice bath) before taking a reading. Make sure to not let either probe contact any part of the container, especially during the boiling water test (the bottom is much hotter than the boiling water).

2. Here's the extra test. Put some hot water from the tap into the same container and put both probes into that. The water will probably be between 125 and 160 degrees. This gives you an in-between reading to test the linearity of each probe. This test will not tell you which probe is more accurate, but it WILL eliminate the whole issue of whether the probes are giving you different readings because of hot spots in your smoker or oven. It is absolutely amazing how large a difference in temperature you can get inside a hot enclosure.

3. If you really want to get into this, you can repeat the side-by-side test using a deep fat fryer. This is a little tougher because the oil won't stop at a specific temperature, the way water does when it reaches the boiling point. What I'd do is get the oil to 350 (nominally) and then unplug the unit. Stir the oil with both probes next to each other (you could even tie them together with a piece of wire). Take the measurements after about a minute.

Finally, if you are really concerned about this, you can get a laboratory grade thermometer and test against that. You can get these from various lab supply houses. If you don't want to go that route, you can get a Thermapen. Each unit is calibrated at the factory and has electronics that, once calibrated at the 32 and 212 points, pretty much guarantees accuracy at all other points.


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## Bearcarver (Nov 21, 2018)

I think there's too much worry here about perfect Therms:
Mine have never been "off" by more than 2° in a boiling water test, however what would 5° or 8° off hurt?
The only meats I care that much about IT are my Prime Ribs, which I like to end up at 142°, but I can accept between 138° and 144°.
And Pork I pull at or slightly below 145°, because I want the final to be safe at 145°, and depending on the Smoker Temp I use, the carry-over won't be more than about 2°.
All the rest, if I'm 2, 3, or 4° off, Big Deal.

And as far as Smoker Temp, if your Smoker is reading 225° and it's really 230° or even 235°, Big Deal.

Bear


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## gary s (Nov 21, 2018)

Good advice, I'll check my Temp gauge on my smoker once a year, maybe twice if I have concerns.
It its within a couple of degrees no biggie. A couple of degrees one way or the other in no big deal unless you are going for the absolute FDA Minimum Temp, you sure don't want to be under but I always take mine a little above that anyway.
Now if you are shooting for that perfect Rare, Med. Rare, or Med. you need a really accurate Temp gauge/Thermometer.
All I am saying is 1 or 2 degrees is no biggie and you probably couldn't tell by looking anyway. 

Gary


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## bregent (Nov 21, 2018)

C'mon folks, he's talking about a difference of 50F!  The use of non distilled water or not adjusting for elevation would have a minor effect on temperature. It is also irrelevant as it would affect both thermometers the same.  Since they are reading the same in ice and boiling water so the response is linear.  Something else is going on.

Solman, do all 4 probes of the Inkbird read the same when testing at the same time, and is the Mav probe in very close proximity to the Inkbird's?


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## solman (Nov 21, 2018)

bregent said:


> C'mon folks, he's talking about a difference of 50F!  The use of non distilled water or not adjusting for elevation would have a minor effect on temperature. It is also irrelevant as it would affect both thermometers the same.  Since they are reading the same in ice and boiling water so the response is linear.  Something else is going on.
> 
> Solman, do all 4 probes of the Inkbird read the same when testing at the same time, and is the Mav probe in very close proximity to the Inkbird's?



yes, all 4 inkbird probes are identical. all thermometers and probes are nearly identical in ice and boiling water. all probes were zip tied together for ice/boil water testing. they were also zip tied in the oven where it showed 50F difference. in the smoker they were on probe clips next to each other.

i think i'll buy a small chicken and insert both thermometer probes into each breast, and pull it once ONE of the probes reaches a safe temperature of 165F, and then see if it's done or not. if it's done, i know i can trust that probe. if it's not done, then i know the other probe is likely more trustworthy.


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## johnmeyer (Nov 21, 2018)

I'll admit that my detailed account of how to do a proper calibration was overkill for this particular situation, but I'm not sure the snarky reply was needed.

Unfortunately, what may have gotten lost in my long reply and the following responses was the key piece of advice I gave: put BOTH probes into water or oil at some temperature other than 32 or 212 in order to check the linearity. Tie them together so they are right next to each other in the liquid (water or oil can also have significant hot spots).

It is actually pretty amazing how much temperature difference you can have in an enclosure, on a pan, or even in the middle of some liquid. If you have an instant read thermometer you can see the difference in liquid as you move it around. For an enclosure a "point 'n shoot" instant read infrared thermometer reveals all sort of big differences. In a hot enclosure, 50 degree variations are not at all uncommon.


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## mosparky (Nov 22, 2018)

I just want to clarify. I hope you are using the Mav probes with the Mav unit and Inkbird with Inkbird. Seems like a no-brainer, but I've seen worse mistakes made. I have no idea if one will plug into the other, but I think it's a safe bet they are not interchangeable even if they did. There are internal, technical things that make it highly unlikely, but could explain the exact issues you are talking about.


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## Bearcarver (Nov 22, 2018)

mosparky said:


> I just want to clarify. I hope you are using the Mav probes with the Mav unit and Inkbird with Inkbird. Seems like a no-brainer, but I've seen worse mistakes made. I have no idea if one will plug into the other, but I think it's a safe bet they are not interchangeable even if they did. There are internal, technical things that make it highly unlikely, but could explain the exact issues you are talking about.



Yup-Good point---I doubt if they are interchangeable. Even the probes from my ET-73 aren't interchangeable (don't fit) with my ET-732.

Bear


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## solman (Nov 22, 2018)

The inkbird is new and probes are differently shaped, so the probes were definitely not mixed up.

Edit, inserted the inkbird probe into the Maverick and it wouldn't recognize the probe.


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## solman (Nov 22, 2018)

I have a 13lb turkey being smoked and have one Maverick probe in a breast and an Inkbird probe in the other breast. At initial entry, each probe read identical 37F. At 1.5 hours, the inkbird read 129F and Maverick 100F. 

I then took a cold inkbird probe and inserted it into the Maverick side of the breast. After a few seconds it read the same as the other inkbird. Strangely, after a few seconds i reopened the smoker and touched the 2nd inkbird probe and it was way too hot to the touch. That makes me think the inkbird probes are quickly absorbing the ambient temperature causing it to read much higher than the food temperature. 

It's been 2.25 hours now, and the inkbird is reading 165 and169, but the Maverick is showing 136. I don't trust the inkbird. I'll wait for the Maverick to read 163 before i pull out the turkey .


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## bmudd14474 (Nov 22, 2018)

I just did a few on the ink bird and found it to be off. My review is in the carousel on the main page.


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## solman (Nov 22, 2018)

bmudd14474 said:


> I just did a few on the ink bird and found it to be off. My review is in the carousel on the main page.



Got a link to it? I can't find it on the main page .


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## bmudd14474 (Nov 22, 2018)

https://www.smokingmeatforums.com/t...bluetooth-wireless-thermometer-review.281433/


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