4 Reasons Why Your Oven Isn’t Heating Evenly

If you find that your food is overcooked in places and undercooked in others, the issue may be that your oven is not heating evenly. This guide outlines the four most common reasons for an oven to heat unevenly, and how to fix the issue. 

1. Your oven is not level

One common reason an oven is heating unevenly is that it is not level. Ovens commonly stand on four feet, and it is possible for them to get knocked out of place. Self-leveling feet are common on appliances, which means the front feet are adjustable and the back feet are designed to adapt. 

To level your oven:

• Take a bubble level and test the top and bottom surfaces of your oven. 
• If they are not level, you must adjust the front feet. On most models, the feet can be adjusted by screwing or unscrewing them. 
• Adjust the feet until the top and bottom surfaces of your oven are level.

Just as uneven cooking can be caused by an oven that is not level, the issue can also be caused by a crooked oven rack. Racks may warp over time, bend, or be installed incorrectly in the tracks.

To level your oven racks:

• Check to see if the oven racks are flat by using the bubble level. Also check the tracks that the racks slide into.
• Try placing the oven racks on the worktop on some old towels. You can tell if the racks are able to lie flat without wobbling by looking at them.
• While the racks are removed, check the rails for impediments, bending, and structural issues.
• If you find the oven racks are the issue, you can readjust or replace them. New oven racks can be ordered from your oven manufacturer. 

2. Airflow in your oven is restricted

Another typical reason for uneven baking is airflow restriction in your oven.  This is caused by two main issues:

Airflow restriction caused by foil lining

Some people line the interior of the oven with aluminum foil to catch spills or drips. However, if you cover the bottom rack with foil, airflow will be restricted, and your oven won’t cook your food evenly. 

The thermostat in your oven may also be fooled by aluminum foil since it reflects heat, making it more difficult for your oven to maintain a constant temperature inside.

Airflow restriction caused by overcrowding

An overcrowded oven can also restrict airflow. In some homes, baking trays and pans are kept in the oven, but this is not a good idea when using it to cook. Some of the heat is absorbed by pans, which prevents it from reaching your cooking vessel. In addition, unequal distribution of pans can lead to an uneven distribution of heat, which will cause your food to cook unevenly.

The answer? No matter how convenient it is, do not store pots and pans in your oven. If you do need to use your oven for storage, make sure to make room for it before heating it up. Check every time before turning on the oven if you have a tendency to forget cookware.

3. An element is faulty or broken

If the bake or broil elements are burnt out or not working correctly, the oven will heat unevenly. If only the top (broil) element is working, your food will be burnt on the top and undercooked on the bottom, and vice versa. You can test to see if one of the elements is burned out by completing the following:

• Preheat your oven to medium to high heat. Wait until it starts to get hot. 
• Look into the oven while it is still at the heating stage. You should be able to see whether the elements are glowing red hot and whether heat is radiating from them. If one of the elements is not working at all, you will need to replace it. 

It is also possible for both elements to be heating, but have damage which means they are not heating evenly. You can find out exactly where the issue is in the element by doing a test for hot spots. 

How to test for hot spots:

• Take a whole loaf of white bread and arrange the pieces in a grid on the oven racks. 
• Either test the toast on the middle rack alone or test it simultaneously on the top and bottom racks.
• When the bread is medium brown, remove it from the oven and inspect it for uneven browning. You can identify the issue since the grid will show you precisely which areas of the oven are cooking more quickly than others. For example, if the bread is evenly browned on the bottom, but the pieces on the top right side of the oven are burning, the issue is likely to be with the top element. 

4. Faulty temperature sensor

Over time, the oven’s temperature sensor may become less accurate. To begin with, check whether the sensor is in contact with the oven wall, as this will cause the oven to heat incorrectly. If it is, move it so it is away from the wall.

An ohmmeter can be used to check the sensor’s functionality as well. The resistance reading of the temperature sensor should increase in step with the increase in oven temperature.

If the temperature sensor is broken, replacing the component is a simple DIY remedy. You will be able to order a replacement temperature sensor from your oven manufacturer.