Top and middle rows of biscuits after our hot spot test.
I fell into a deep slumber during The Weekend’s LV Super Bowl halftime show and badly overcooked my Oven-Roasted Buffalo Wings. The wings on the bottom rack were salvageable but those on the top shelf were literally toast. This motivated me to mount an experiment to identify the different heat zones in my new BlueStar oven.
Bottom rack biscuits from oven hot zone test.
I bought a couple tubes of those pop-and-bake biscuits and a dozen Simpson plates from Lowe’s. (They are used in construction to strengthen a joint where two boards are connected.) One biscuit went on each of 12 plates which were labeled as to shelf (top, middle, bottom) and corner of the oven. I then followed the directions on the package and cooked my biscuits for 13 minutes. The results are in the pictures. Top got the darkest, then middle, then bottom. (There are some more subtle differences like top right being darker than top left, which may get further investigation in time.)
Next I got my laser thermometer gun (affiliate link) and spot-checked the temps in roughly the same corners. (Rough is the operative word: I aimed it as best I could but may have picked up rack vs a section of the wall of the oven, and the experiment was definitely skewed by repeatedly opening and closing the oven door.) Back is hotter than front by a significant amount in every case: well over 400 degrees F for an oven set to 400 degrees in the back, well under 400 in the front.
The laser gun measurements don’t correspond in any way to the results of the biscuit test, suggesting it’s the air circulation inside the oven (and I’m talking the natural circulation with help from the BlueStar’s fan, because the convection was not turned on) that makes the difference as to hot spots. (The big oven in the BlueStar has the ability to load an entire sheet tray in the slots which are normally used for the racks, which will certainly have an effect on air circulation. Looking forward to another experiment with this.)
The best news in this test is the lack of hot spots where one area of the oven is much hotter than the rest. I now have a broad understanding that in my oven the higher you go, the hotter you will get. Most items will go on the middle rack, the bottom will be reserved for slow cooking (the rack rolls out on bearings, making it easy to load a heavy pot) and the top for quick heating.
So, try this test in your own oven. The biscuits are cheap and the Simpson plates were less than a buck apiece and can certainly be used for something else (maybe even a construction project) in the future.
P.S. Tom Thibeault of BlueStar told me the hottest spots are the top front and the bottom back. My test doesn’t bear this out. It’s not surprising that two hand-assembled ranges from the same manufacturer would have different hot zones, another reason to do your own test.
Interesting test. Question. Could I use parchment paper instead of the metal to perform the test? Second question, baking cookies is one thing, roasting a chicken, beef roast, or turkey is another issue altogether. I would suspect that the various hot spots will cancel each other out over a two hours or longer roasting time. What are your thoughts? I suspect that any items lined up smack in the middle of the oven would have a great balance of heat dispersion.
The reason I used the metal plates was to support the little biscuits on the oven racks. I could have used many cookie sheets if I had them, but this worked well enough. Actually better because a cookie sheet might have interfered with air flow. And yes, after this test I’d feel comfortable cooking the average dish (like a whole chicken) right in the middle of the oven. But I was worried about anomalies that might make one spot unusually hot so I’m relieved I didn’t find any.
By the way, I’ve made a few more pizzas in the BlueStar since the disastrous first attempt I reported a while back; will have an update when I am comfortable showing my work (not quite yet). I was worried because sometimes they got charred right at the back but I’ve realized I was jamming the stone right against the back wall of the oven so they came in contact with the metal. Recent pizzas have been pretty good but will be better.
Also, I was very intentional at wanting to isolate each biscuit in its corner so I could get a really good reading on that exact spot.