how to check temps in back heat rack?

All my racks so far are belly heat. I think my next build is going to be back heat (hatchling shoebox rack).

Usually I temp gun the surface on the floor of belly heat set ups. But since back heat won't cause the floor to be the hottest place, how do I measure? Do I just temp gun the back wall?

Quote:

---

Originally Posted by hungba

Do I just temp gun the back wall?

---

:) :sweeet: You want to measure the hottest place in the enclosure (regardless of whether you think they can reach there or not). It is a temp gun, afterall - the major benefit is its flexibility in places you can measure quickly!

I would not suggest an IR gun in this case it is a fantastic tool (I own 4 with different DS) but as with all tools you need to understand the limitations a translucent plastic is not likely to produce accurate readings (emissivity is way off of the calibration point) and it is reflective so it can reflect the reading. I would place a probe at the back wait 30 min and take the reading and double check the ambient air temp wile you are at it. (although if memory serves you are in a warm country so this isn't a problem. ? or do I not recall correctly?)

Small demonstration, an accurate IR gun measuring a target very different emissivity. It is reading 12ºF off. (23.4 is the accurate reading there is a highly accurate traceable thermometer under my hand (the large box one).

http://images58.fotki.com/v85/photos...CA_0373-vi.jpgHosted on Fotki

I also use a thermometer with a probe as kitedemon suggested. I put the probe in the back of an empty tub and check the temperature after an hour.