When your oven has hot and cold spots - how to fix it? will a new bake element fix this problem or a new thermostat

The bake element
is the heating element that is found at the bottom of the oven. Most electric ovens use both the bake element and the broil element in a bake cycle, with the bake element performing 90% of the heating. If the bake element isn't working, the oven may not heat. To help determine if the bake element is defective you should first do a visual check. If the element is blistered or separated then it should be replaced. If the element appears to look normal, then turn the oven on to a bake function for a minute and then turn it off.

Check the element for signs of heating and if it is still cold then it may be defective. Disconnect the power and then remove the back panel. First check the wires as they may have become loose or corroded. If the element appears to be fine visually, test it for continuity with a multi-meter. ( by placing the each of the meter prongs on each end of the heater element connectors) If the element is burned or no longer has continuity, it will need to be replaced. Depending on the manufacturer of the element, you will normally read between 19 ohms and 115 ohms

The oven safety valve
(also called the gas valve) is the part that ensures that gas is not released until the igniter has reached the correct temperature needed to ignite the gas. While this part can fail, it is uncommon. If the hot surface igniter does not glow you should first verify that you have voltage to the circuit. This is a live voltage check and should be performed by a qualified person. If voltage is lost at the valve terminals then you should verify the continuity of the bi-metal in the valve using a multi-meter.
Sometimes the oven thermostat or oven sensor can be calibrated wrong, or it may be faulty. If your particular range has an oven that uses an electronic thermostat, and the oven temperature is off by tens of degrees, you probably have to replace it.
On most units that have a mechanical thermostat, you can actually remove the thermostat knob, and adjust the knob to more accurately represent the actual setting of the thermostat. On many models, there's a screw on the back of the knob with a small calibration plate or ring. You can loosen this screw and adjust the calibration plate. Remember to tighten the screw again. If yours isn't adjustable, and the temperature is off by a large amount, you should just replace the thermostat.

Or Oven safety valve needs to be checked with multi meter ohms / voltage

thermostat is bad

The fan does not produce hot air. It just circulates it. The thermostat turns on the heating element and the fan moves the hot air around. Unless you have an odd working machine. Baked bread for years an it only moves air for even heat.

the oven sensor could be bad,its a small rod inside the oven cavity near the top,or you could have a bake element with a "hot-spot" in it that can no longer pass enough current to properly heat the oven to the correct temperature setting(most elements with a hot spot will show a discolored area on the element where its been overly hot)this is the "hot-spot" it will soon break apart there

it could be the oven temp sensor rod located near the top of the inside of the oven,or possibly the bake element has a hot spot on the element and can no longer pass enough current thru this spot to correctly heat to your settings a hot spot on the element will look discolored in this area

It would either be the bake element is bad, or the control sending power to it.

hello there
Usually, when an oven won't heat up or bake, it's because the bake element is burned out. The bake element is the black, pencil- thick tube at the bottom of the oven. When the oven heats, the element glows red. This element has an expected life-span of several years. It may last for only one; it may last for many more. When the element burns out, you need to replace it. Now if the oven It bakes poorly Here are two instances of when food "bakes poorly:" When the food you're baking is done on top but not on the bottom--or when baking just takes far too long to finish--the bake element may be burned out. You may get fooled into thinking it's working, because the oven is hot inside. But many electric ovens use the broil element, too, during the preheat and bake cycles. So the food may be getting heated only by the broil element, which causes poor baking results. If the bake element is burned out, replacing it should solve the problem. Otherwise, you need to further troubleshoot the oven's electrical system to locate the defective wire or component. When the temperature is consistent but too high or too low, it could be one of several different things. First check to see if the thermostat sensing bulb has come loose from its holder. It could be lying on the floor of the oven or resting on the heating element. This would cause the oven to not heat correctly. If the thermostat bulb is not dislodged, it's likely that the thermostat or sensor is either mis-calibrated or defective. Electronic ovens with a digital display use a sensor to monitor oven temperature. To solve temperature problems for these models, you may need to replace the sensor. On some digital-display models, you can calibrate the temperature using the key pad. See your operator's manual for details. Ovens without a digital display often use a mechanical system for controlling temperature. On many of these units, you can remove the thermostat knob and adjust the knob itself to more accurately represent the actual setting of the thermostat. If, when you remove the knob, there's a screw on the back of it with a small calibration plate, you can loosen the screw, adjust the plate, then tighten the screw again. If the knob isn't adjustable, and the oven temperature is off by more than 30 to 40 degrees, you need to replace the thermostat to solve the problem
Hope thisis very helpful for you
Best regards Michael .

If it is convection bake you have to turn the temp down (25 degrees or so) that is listed in the recipe.

The broil setting is not used to bake because it operates differently from the bake setting. So, don't go to the broil setting at all.
The element for bake is under the floor of the oven. You have not indicated whether it is gas or electric, but both of these can have issues with the burner or element.

If you are baking on the correct setting and the oven is heating from the bottom, not the top, this can be caused by hot spots that are created by elements/burners.

to check, look under the floor of the oven. Turn the bake heat up to high and see if the flame is uneven. For an electric oven, the color of the element should be evenly red, no brown spots.

If you are using an oven thermometer, move the thermometer to the spot in the oven that seems to be burning things the most.

The problem is usually a contactor or relay. The thermostat usually doesn't directly control the elements. Follow the wiring diagram or look at the wires from the thermostat. they usually go to a small box and then to the elements The contacts may sometimes stick or always stick. This part is a lot cheaper than the thermostat. Another problem is a burned out element. (Usually the bake element) This can short to ground and not let it turn off. When the elements are on they should glow evenly all over with no hot spots. Look at the broil element also. It is usually at least part way on during baking.