# TP20 vs Tru-tel accuracy’s



## michael0506 (Jan 8, 2019)

Hello all,

I bought a new LoneStar Grillz branded tru-tel thermometer for a restored LSG offset smoker!  I also bought a thermo pro TP20 Wifi and I have done 2 long smokes with them!  The TP20 always seems 30-50 degrees higher,  so is the TruTel usually accurate out of the box or maybe the TP20 is off!


Any input thanks,  I may just get a Fireboard thermometer, the TP20 is good but I don’t like that it doesn’t stay lit when watching the temps and it seems way off!


----------



## michael0506 (Jan 8, 2019)

thanks, does anyone use this forum!


----------



## tallbm (Jan 8, 2019)

michael0506 said:


> Hello all,
> 
> I bought a new LoneStar Grillz branded tru-tel thermometer for a restored LSG offset smoker!  I also bought a thermo pro TP20 Wifi and I have done 2 long smokes with them!  The TP20 always seems 30-50 degrees higher,  so is the TruTel usually accurate out of the box or maybe the TP20 is off!
> 
> ...



Hi there and welcome!

The answer to your question is to test the probes of your TP20 to see if they are accurate.  You do this by boiling some water and then using the TP20 probes to measure the temp of the water but don't submerge the probes up to the wire as that may ruin them.  The probes should read 212F or very very close to it.  You can also put the probes in ice cold water to measure the lower end as well if you know about what temp the water is to test against the probes.  

Do the same measurement with your tru-tel and compare.  Boiling water doesn't lie but your thermometer probes just might :)


----------



## pc farmer (Jan 8, 2019)

^^^^^^^    This.    

And yes alot of people use this forum.     Give some time for people to answer.


----------



## michael0506 (Jan 9, 2019)

Thank you for the response!   Great forum!


----------



## michael0506 (Jan 9, 2019)

pc farmer said:


> ^^^^^^^    This.
> 
> And yes alot of people use this forum.     Give some time for people to answer.




Thanks Adam, I'm just antsy!  great forum!


----------



## SmokinAl (Jan 9, 2019)

It depends on where the therms are located also.
I have 3 Tel-tru's on my Lang & have them all at the grate level.
If your Temp probes are in different area's, then you will in most cases get different readings.
But checking their accuracy is the first step.
Al


----------



## michael0506 (Jan 11, 2019)

Here is the Tel-Tru, ThermoPro TP20 and M4 readings in Hot and Cold test! I can't tell on the Tel-Tru what the cold reading is!

How do they look, for some how during the cooks the ThermoPro is always between 20-50 higher and dont know if its the T-T of thermoPro that is off but the testing seems the same!

T-T hot and cold










ThermoPro both probes seemed about even!











M4

Hot 211
Cold 32
Top
OnlineOnline


----------



## tallbm (Jan 11, 2019)

Both therms look to be on.

My guess is that the placement of each one is where you get the difference.
For example on my BBQ grill the thermometer built into the lid is always way cooler then the temp at rack level.  This is easy to explain in the fact that the lid thermometer is a good 8 inches higher and to the front of the whole grill.

Another example is that I place 3 temp probes at rack level of my MES electric smoker.
Left back of the rack is always hotter than dead center of rack and quite a bit hotter than front right on my smoker.
If left back is 250F then front right is often 235F and middle is usually about 244F.  
The next rack up is going to be roughly 20F lower in each of the same spots.


Natural hot spots vs cold spots and however heat/air flow is affected by your smoker and/or the meat and pans in the smoker along with probe placement will all cause potential differences in the temp the thermometer reads
I always run 3 probes so I know highest, lowest, and middle area temps of my rack so I can assume that all areas of the rack are within that range.  This allows me to understand very well what my smoker is doing at all times :)

I would suggest you follow whichever is closer to the meat you are cooking and you figure out which area of your smoking rack is hottest and which is coldest.  Every other place on the rack have a temp in that range.

I hope this info helps :)


----------



## michael0506 (Jan 11, 2019)

tallbm said:


> Both therms look to be on.
> 
> My guess is that the placement of each one is where you get the difference.
> For example on my BBQ grill the thermometer built into the lid is always way cooler then the temp at rack level.  This is easy to explain in the fact that the lid thermometer is a good 8 inches higher and to the front of the whole grill.
> ...




Thanks for the reply,

I retested once again and the Tel-Tru came out at 212, I left in boiling water 3 minutes,













 and the Thermopro 2 probes as well, thermo 2nd probe only 1 off at 211~


----------



## michael0506 (Jan 11, 2019)

Thanks all for the help and reply's!


----------

