Puzzled about internal temp

[pelallito]

I’ve made baby back ribs twice and gotten strange readings from my smoke alarm box probe.
Both times I’ve gotten very low temperature reading. But my mini loaf pan level went down dramatically.
I checked my number one without food in it and it was exactly where it should be. Both times I made 3 racks cut in half and spread out over three racks.
Prior to that and I’ve done salmon, a Boston butt, and brisket flats with perfectly normal temperature readings.
Why the weird temp reading?
Thanks for reading this.
Fred

 

[Pork Belly]

It might be helpful if you told us:
The set temp
The actual "strange readings"
The actual "low reading"

When you say "normal" does that mean the SI was running at the set temp?

 

[pelallito]

Hi Pork Belly,
I have not messed with my rheostat as yet. If I set it to 200 the temperature swings between 250 and roughly 200. Which gives me an average temperature of 225.
Both times I did the ribs using that temperature setting the internal box temperature probe never gave me a reading above 170.
I did not use a meat probe.
As I said I checked it empty and it was on the money.
I guess I’ll just have to make more ribs and see if it happens again.
The first batch was just dry rub. The second I brined. Nobody complained about the taste, or how they were cooked.
I’m just puzzled about low temperature reading. I’ve ordered and received another temperature probe if the first was faulty.
I hope that I explained it better.

 

[Lonzinomaker]

Empty smokers don't work the same when they have a load in them.  Try it with a meatloaf tin 1/2 full of damp sand and see what results you have.

 

[pelallito]

I will try that this weekend, or as soon as I can get some sand. Might be Monday , have lots of sand at work.