The Fresh Loaf

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Is this oven thermometer malfunctioning, or is my oven misbehaving?

ALeous's picture
ALeous

Is this oven thermometer malfunctioning, or is my oven misbehaving?

I just bought an oven thermometer, and it’s not behaving consistently… eg, I set the oven to 350, and at first the oven thermometer was reading just over 500 degrees; a little bit later however, the oven thermometer was reading around 400. Is it common for ovens to change temperature throughout the course of running? Or, are there any pro tips on using an oven thermometer? Thanks!

idaveindy's picture
idaveindy

How close was it to the lower or upper heating element?

it sounds  like it was getting direct (radiant) heat from one of the elements, which are always much hotter than the air temp.  When the elements turn off, then the thermometer can read the air temp.

To avoid direct (radiant) heating, put a pan or piece of aluminum foil between the thermometer and the heating element(s) so the thermometer does not get heated directly by the heating elements.

it's like how you place a thermometer outdoors: you don't put it in direct sunlight, you put it in the shade.

Hope this helps.

ALeous's picture
ALeous

@idaveindy - I think you are right, I think it's too close to the lower heating element! I will move it to a different place and give that a try, but I bet that's it. Thanks for the suggestion!

idaveindy's picture
idaveindy

keep in mind that direct (radiant) heat is "line of sight", not just directly up.  The thermometer does not have to be directly above a portion of the heating  element to be affected by the "direct" heat.   As long as the two "see" each other, the thermometer is picking up extra heat.  So that's why I recommend using something as "shade", like we do with outdoor thermometers.

The inverse square law also holds.  When you double the distance between an object and a radiant heat source, the  object will then receive 1/4th as much radiant heat as before.

buck upson's picture
buck upson

In my electric oven, I noticed my oven can pre-heat to 350°F in less than 15 minutes, but....

For the next 30-40 minutes the temperatures swing wide before the oven reaches equilibrium and settles down.

If you have to open the oven door to read thermometer, that introduces more possibilities for false readings.

I found a remote digital thermometer with in-oven probe for high AIR temps to be beneficial, but costly.

If you are really interested in your oven's temp, you might google:  "Test oven for hot spots"

 

 

 

suave's picture
suave

Ikea meat thermometer costs $7 and has a heat-resistant (to 480 F) cord.  IR thermometers can be found for $20-25 and are great for detecting hot spots.

ALeous's picture
ALeous

thanks for the tip! I'll look into that, if I can't get my current one to behave.

BobBoule's picture
BobBoule

Variation is normal but that seems extreme to me.

What I do is to put a cast iron layer on the lowest rack (my cast iron pizza cooker), below the rack that I'm baking on, to store heat and to even out the temperature swings.

Then got a decent (yet affordable) thermometer and got far more accurate readings (I still leave the cast iron on the lower rack) and all is well now.

Cooper-Atkins 24HP-01-1 Stainless Steel Bi-Metal Oven Thermometer, 100 to 600 Degrees F Temperature Range:

https://amzn.to/3bnYbqv

 

ALeous's picture
ALeous

good tips. thanks Bob Boule!