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I'm quite suspicious that my electric stove runs hot. Recipes that suggest medium-high on my stove are incredibly, incredibly hot and you can feel 'high' radiating heat from across the kitchen.

As such, I've semi-recently purchased an IR thermometer - what pan surface temperature should low, medium-low,medium,medium-high, and high approximately register as?

rfusca
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    It might not be a bad idea to have a qualified repair person check the stove. It may be unsafe, and/or it may be using far more energy than is necessary or helpful. – Caleb Feb 18 '12 at 07:20
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    Yes, Wye vs Delta wiring confusion could show exactly the effect described. If you have no idea what I mean, have an electrician look at it. – rackandboneman Nov 14 '17 at 19:37

9 Answers9

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They don't correspond to a temperature, they correspond to a rate of heat input.

The elements in your oven are connected to a thermostat with regulates their temperature, they are really constant heat/fixed temperature devices, like the heat in your home. The oven turns the elements on and off to regulate temperature, but the elements are only ever ON or OFF.

The stovetop elements, by contrast, are variable heat/variable temperature. There is no thermostat, but the elements can be variably adjusted between MAX and OFF. For every setting the temperature will just keep getting hotter and hotter (unless something is removing the heat, like cooking food) - the higher settings will just get hotter faster.

The important thing to know (for an electric range) is the wattage of the elements - most 8" elements are ~2500W, and most 6" elements are ~1500W. But there is a lot of variability. Additionally, if you are living in a home with 240V power but have recently lived in an apartment (which likely had 208V power, but 240V elements installed in the oven, even if you didn't realize it), your heater elements will seem much hotter than before. It is also possible that the oven maker or previous owner installed higher wattage elements (perhaps by installing elements intended for a 208V service in a home with 240V service, which would have the effect of "turbocharging" them a bit).

Temperature measured with an IR thermometer may not be useful for you to determine if your oven is hotter than usual, since an empty pan on Low will still reach 400+ degrees (it will just get there slower).

What might be more useful is to find out what setting people do certain cooking tasks at, and see if that is different than what works on your oven. You can also remove the elements and find the voltage/wattage stamped on the bottom - let us know what those values are and we may be able to tell you if they are abnormally high.

Personally, I sweat onions on 4/10, fry an egg at 6/10, simmer soup at 2/10, and maintain 1 gallon water at a consistent, but not vigorous boil at 8/10.

Sam Ley
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  • Hmmm...I have an empty pan on low, I'm going to monitor temp. My stove burners don't have a wattage marked. – rfusca Feb 17 '12 at 03:14
  • We could probably do a little informal experiment if you used a pan that many people have, like a 10" Lodge Cast Iron? Then you could compare temperature at 30 sec, 60 sec, 90 sec, etc. That would give us the clearest view of RATE, which is the important quantity here. – Sam Ley Feb 17 '12 at 03:22
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    So, this just totally isn't my experience here. I set my burner on low-medium and after about 15 minutes it had risen to ~ 380. In the last 20 minutes it hasn't risen a single degree. By that logic, 380F would be the max of my stove. I turn it to medium and within seconds it jumps to 450....so, explain that? – rfusca Feb 17 '12 at 03:57
  • Note, I'm not saying you're wrong about how they work, I'm just trying to justify what I see empirically. – rfusca Feb 17 '12 at 04:06
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    You are seeing the effect of equilibrium - the heating element is pumping heat IN, the pan is radiating heat OUT, and at some temperature the IN and OUT will match, and the temperature will stabilize. But this will be very pan dependent, and could be hazardous to test in every case because some pans/settings will form an equilibrium that would be above a safe temperature for non-stick surfaces, or in some cases, could melt thinner aluminum pans. If we tried the same pan that you are using on a few stoves, we could get a better comparison of different equilibrium temps, which would be useful. – Sam Ley Feb 17 '12 at 04:20
  • (This is a 10" Lodge griddle) that was my suspicion, but then it means that there's still a practical temperature for each setting/pan/food combo. Low and medium do not correspond to the same temp if left on long enough - which is the answer above. – rfusca Feb 17 '12 at 04:34
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    I've got a 10" Lodge Skillet, which should be pretty close. I'll try it out and give you a low and medium equilibrium temp. Though it should be noted that these equilibrium temps aren't that useful for cooking, because they will drop very quickly when food is in the pan, and many cooking processes depend on pumping heat into the foot at a certain speed, rather than a max temp. What they can be good for is comparing different stove tops against each other. – Sam Ley Feb 17 '12 at 04:35
  • So, fun fact. Leaving my stove on high for 15 minutes or so was enough to ignite whatever previously charred bits of whatever were left in the drip pan. There's a reason for a fire extinguisher in the kitchen. – rfusca Feb 17 '12 at 04:36
  • I've got the 10" Skillet too, I'll fire it up on the lowest setting and medium. Any above that starts to take my seasoning off the pan :/ – rfusca Feb 17 '12 at 04:37
  • 10" Lodge skillet - 15 minutes on 4/11 - 360F. 4 more minutes on 6/11 got to 470F and started to smoke, so I backed it off. – Sam Ley Feb 17 '12 at 04:59
  • Mine has seven positions, trying to match yours decimal-wise - 10" Lodge skillet 2.5/7 340F - 4 more minutes on ~3.8 (just under 4)/7 - 580F. – rfusca Feb 17 '12 at 05:21
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    Just a nit-pick. Stove-top burner controls have a thermostat fully contained inside the switch. It's a bi-metal spring where turning the know adjusts the tension on the spring, causing the heating element to stay on longer/shorter. There is no feedback to the thermostat from the burner. In practice, you can think of it as a sort of timer that controls the on/off duty cycle. – Les Jan 10 '13 at 16:23
  • I'm afraid Sam Ley (above) is wrong about the voltage in a house vs. an apartment. All modern residential systems in the USA, which are connected to a public system, are 120/240 volts. The confusion may arise because large buildings, such as apartment buildings, are often supplied with 3-phase power, but that 3-phase is transformed to the standard 120/240 volts before entering the apartment units. –  Feb 08 '16 at 00:03
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    Steve - apartment buildings supplied with 120/208V three-phase power aren't transformed to 240V. They can't be, because the apparent 208V is due to the 120 degree shift between the phases, and transformers can only affect magnitude, not phase angle. Because of this, there are many situations where 240V appliances will run at 208V - for a heating element this isn't a big deal, it will just run at a slightly lower wattage, since the resistance of the element is fixed. I design commercial and residential electrical distribution systems and we run into this all the time. – Sam Ley Feb 09 '16 at 01:27
  • Power for a purely resistive element is V^2/R... Going from 208V to 240V on the same element means a 33% increase in its power output.... – Gert van den Berg May 30 '18 at 10:30
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Here is what cook surface temperatures correspond to these labels:

High: 450° to 650°+
Medium-High: 375° to 449°
Medium: 325° to 374°
Medium-Low: 250° to 324°
Low: < 225° to 249°

On my electric stove, I've so far roughly figured out this system, using an IF thermometer, measuring a matte cooking surface:

High: 5 to 10 = 465° to 700°
Medium-High: 4.0 = 429°
Medium-Low: 2.8 = 272°

I'd say calibrate your own electric range, you should be able to find a reliable thermometer for under $20. Use a flat pan, preferably enameled steel, put some oil in it with a high smoke point, and measure away. Careful not to damage your pan, of course.

It's possible that the common quick-boil feature serves to distort the heat output - I do know someone with a gas stove where the highest setting is quick-boil, and there's a similar temperature distortion (where the simmer setting is much hotter than it should be, etc).

mech
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Fin Hirschoff
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Rather than empty pan temperature, I suggest adding a quantity (like 2 cups) of water and measuring the time from off to boil. As other posters have indicated, stoves vary in power (heat input over time) without respect to temperature. By the way, electric ovens usually come in constant power (except those with "preheat" and "clean" settings -- which use the broil as well as bake element) and a thermostat (which is a switch activated by a temperature sensor) to turn the element on and off. (the knob for the burner eyes also has a thermostat, but it's not connected to the eye -- it uses a tiny heater inside the switch assembly to open and close a bi- metal switch -- it's turning on and off all the time. They use these because they're relatively cheap.)

Assuming that your electric stove elements are "overheating," you can simply not use the "high" setting. Electrical heating elements have negative temperature coefficients -- resistance (and power) goes down as the temperature of the element goes up. Also, as the element gets brighter, more energy is radiated and less is conducted, which means that a lot more energy is required for not much change in temperature once the element starts glowing brightly (you feel the radiant energy from across the room). When heating elements fail, they just stop working -- they won't catch fire or explode.

The biggest problem of too much power is that food gets too hot on the bottom of pots and pans. The food then sticks, cooks unevenly, or is overcooked. The best solution for that is to get to know your stove really well. The IR thermometer is great, but it's great for measuring the temperature of your food and hot oil. The temperature of the bottom of an empty pan is pretty useless information. Also, most IR thermometers have an upper limit of 400f or less. Since most foods char at less than 400f, they're great for food.

Rich Smith
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In my experience, burners vary in calibration pretty significantly. As Sam Ley has pointed out some electric burners may even be installed with the wrong voltage settings, causing them to operate outside of their calibrations.

What I've done for low, medium and high settings in recipes is to develop my own sense of what's low, medium and high. This can be as precise or rough, but universal.

An example of precise would be using an IR thermometer to read pan temps after a fixed time on the stove, which sounds like what you're after. I've only used my IR gun for bbq cooking, since I wanted to make sure I was getting the best possible sear on my steaks.

An example of rough and universal is what I do for stove top--use the smoke point of a common oil, i.e. canola oil, as an indicator of how much heat the stove can deliver in a fixed time.

My personal experience has been that medium-high and high on many recipes means canola oil is slightly smoking and quickly smoking, respectively. Medium would boil a few drops of water in under 5 seconds, whereas low would be where a few drops of water just barely sizzle, if at all. All this is on a medium-thickness saucepan, not cast iron or a cheap, thin skillet (i.e. 5 dollar pan from Ikea)

The advantage of the rough and universal method is that it can be applied to calibrate when switching cooking environments. I've used it while cooking at friends' houses and in vacation homes.

Eric Hu
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If the stove does not use any thermostatic mechanism, there is a way to find out what wattage the hobplates are actually running at: Make sure your home is as "electrically quiet" (nothing turned on that doesn't need to be) as it can be, then run the hobplate with a big pot of water on it for a given time, and check your electricity meter for what is being consumed - if, eg, you get 0,6 kWh after running half an hour, the plate is effectively running at 1200W.

Quicker way: IF you can access a few cm of the actual wires going to the stove (no need to be able to make an electrical contact!), get or borrow a clamp current meter, measure current and multiply by voltage to get wattage.

rackandboneman
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  • You can calculate the power actually reaching the water as well.... (You might want to close it to limit losses...). 4,2kJ heats up 1kg (or 1ℓ) of water 1 °(Celsius / Kelvin)... If you are at sea level (boiling at 100°C) and 1l of water started at 20°C and boils after 5 min (300s), the power is ((80*4.2k)/300) W = 1.12kW – Gert van den Berg May 30 '18 at 10:41
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I have found that, using an IR thermometer to read pan bottom temperature after 5 minutes of heating (the temperature is no longer rising), that high corresponds to 375 degrees F, medium high to 330 degrees, medium to 300 degrees, and low to about 275 degrees.

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  • empty-pan temperatures depend on both stove model and pan construction/size. 2) stovetop cooking temperatures depend on many different factors including amount of food you are cooking; the achieved empty-pan temperatures at some point of time are rarely useful for any kind of decision.
  • – rumtscho Jan 10 '13 at 14:47