Electric, gas, and dual fuel ovens may not heat up to your selected temperature in a given mode for various reasons. When an oven doesn’t heat up all the way, it could end up cooking your food unevenly or even ruin what you’re trying to bake. Beyond just being frustrating, an oven that doesn’t heat up to your desired temperature could actually ruin your food!
Here’s why your oven is not heating up:
- Voltage and amperage problems
- Low gas pressure or no supply
- Blown thermal fuse or limit switch
- Customizable modes and settings
- Dirty or broken gas oven igniter
- Stuck or failing gas safety valve
- Bad electric oven heating element
- Door, switch, and gasket problems
- Malfunctioning temperature sensor
- Defective relays or control board
These typical problems affect all major oven brands, except for the components that are specific to gas and electric ovens or ranges. Also, some of these issues delay preheating, and a few won’t even let an oven heat up at all. Read on to learn why your oven isn’t heating up and how to fix it.
Voltage and Amperage Problems
An active display or control panel isn’t a guarantee that your oven has the necessary power to heat. The display panel actually needs very little electricity to function. Besides, electric ovens have two separate live wires, each providing 110V / 120V. So, just one live wire can power the display panel while the other one isn’t working.
All ovens require electricity, but the power demands and circuitries are different. Gas ovens use electricity to operate the onboard electronics and sensors. Most gas ovens require a 110V / 120V connection. In contrast, dual fuel and electric ovens demand a 220V / 240V wall outlet.
Voltage aside, gas and electric ovens draw different amps. Most electric home ovens in standard ranges draw around or more than 20 amps. Double ovens and industrial models draw even more, sometimes over 50 amps for the larger variants.
However, gas ovens draw much less than 10 amps to power the electrical components. Hence, you can use standard wall outlets and circuit breakers for gas ovens. Electric ovens, on the other hand, need a 240V power outlet with a double pole circuit breaker rated for 30 amps to 50 amps.
Therefore, any voltage and amperage issues due to the electrical setup and circuit breaker are likely to prevent an oven from heating up. The demands for electric ovens are greater, but even gas ovens won’t be able to heat up if the igniter doesn’t have sufficient current.
The power-related problems aren’t always due to the wall outlet or circuit breaker. The wires can be an issue, especially if they aren’t the recommended gauge for the required amps. Also, your oven’s terminal block and onboard wiring could be the problem if either is faulty.
Power surges, overheating, and other electrical issues can cause the terminal block and internal wiring of an oven to fail. When this happens, your oven won’t heat up.
How To Fix
Here is a holistic approach to inspecting the electrical setup if your oven is not heating up:
- Verify whether you have the recommended voltage for your oven or range.
- Confirm if you are using an appropriate circuit breaker rated for the amps.
- Check if the wall outlet is live or use another equivalent power source.
- Don’t use extension cords or any such accessories to power your oven.
- Turn off the breaker and unplug the oven to inspect the terminal block.
- The terminal block is inside the rear access panel of your oven or range.
- Check the terminal block for signs of damage, such as burnt parts.
- Look for loose or frayed wiring and ensure the wires are the rated gauge.
- If the wall outlet has power, you have to check if the terminal block is live.
- Plug in the oven and turn the circuit breaker on to test the terminal block.
- Exercise extreme caution and don’t touch the oven or wires during this test.
- Get a tester to check if the left and right legs of the terminal block have power.
- Electric ovens have 3 legs on the block, but some have 4 (to ground the cabinet).
- Only 2 legs (left and right in electric ovens) are live, each with 110V / 120V power.
- If you want, get a voltmeter to test the voltage of these left and right live legs.
- Measuring the left live leg with the neutral at the center should read 110V ~ 120V.
- Testing the live right leg with the neutral at the terminal block should read 110V ~ 120V.
- Measuring the left and right live legs with a voltmeter should read 220V ~ 240V.
- If the terminal block doesn’t have these readings, you need to replace the part.
- If the wall outlet and oven terminal block have power, check the onboard wiring.
- Check if all the wire harnesses are snugly fit and look for damaged or burnt wiring.
- Replace any bad wires and ensure all the connections are in impeccable condition.
You need to call an electrician if the wall outlet, electrical circuit, and breaker have problems. Alternatively, you can replace the faulty oven part yourself, such as the terminal block, based on your inspections.
Here’s how you can replace your range or oven’s terminal block:
Low Gas Pressure or No Supply
Gas ovens require a steady supply at optimum pressure for the burners to heat effectively. A significant drop in gas pressure can be the reason for your oven not heating up. You should also verify if the gas supply is on for your oven before you get started.
The typical gas pressure is rarely identical in all homes. Single-family homes may have a gas pressure of around 0.30 psi (~20 mbar) at the main line. The regulator may reduce this pressure to 0.25 psi (17.24 mbar), which is what most gas ovens and ranges require.
Multi-dwelling residences and apartment buildings may have as high as 60 psi (~4,000 mbar) gas pressure at the main supply line. Individual homes have regulators reducing this pressure to suit the different appliances. However, these pressures can vary in most circumstances.
For instance, a single-family home may have a long and winding gas line, which will effectively reduce the gas pressure. Similarly, if the piping is narrower than usual, the gas pressure will dip. Thus, you have to check the gas piping and test the pressure at the main regulator to be sure.
If a gas oven needs 7 WC (0.25 psi, 17.24 mbar, or 1723 Pa) of supply, you won’t get it to heat up at significantly less pressure. The flames on the burners would be too weak.
How To Fix
First, you should verify if the main supply valve is turned on. Then, test the pressure at the main line. Finally, check the gas shut off valve on your oven or range. You’ll find this shut off valve near the inline gas hose behind the range or oven.
In many ovens, the shut off valve doesn’t regulate the gas supply to the stove or burners on the cooktop. Hence, the stove may work, but the oven won’t heat up.
Generally, manufacturers set the shut off valve in the “on” or “open” position when they ship their ovens from the factories. However, this valve may be shut off or closed accidentally. Thus, it’s always a good idea to check out the valve behind your oven or range and ensure it is in the “on” position.
Here’s a short video to help you find the shut off valve behind a gas oven:
Keep in mind that your oven may still have a gas supply problem even if the pressure is fine and the shut off valve is open. I discuss this issue in the igniter and gas safety valve sections below.
Blown Thermal Fuse or Limit Switch
Your oven has a thermal fuse or limit switch. Some ovens like dual fuel ranges may have both. The thermal fuse or limit switch is a safety feature to prevent your oven from overheating and from power surges. So, if the thermal fuse blows or the limit switch is activated, the oven won’t heat up.
A thermal fuse is similar to the old breakers in our homes and appliances. You cannot reset this fuse, so the only option is to replace it. In contrast, some high limit switches have a reset button. However, limit switches can break, and resetting won’t solve the problem.
You have to check the manual for your oven to know if it has a thermal fuse or high limit switch. Some companies refer to this part as the thermal cut out. You can also remove the rear access panel of the oven to visually inspect if it is a thermal fuse or high limit switch.
How To Fix
Here are the steps to test, reset, and replace a blown thermal fuse or high limit switch:
- Unplug the oven and pull it gently away from the wall to access the rear panel.
- Unscrew the rear panel to access the thermal fuse or high limit switch.
- Remove the wires from the two terminals of the limit switch or thermal fuse.
- Get your multimeter and set it to the continuity mode to test the fuse or switch.
- Test the two terminals of the fuse or switch with the multimeter probes.
- If the multimeter beeps, the fuse or switch has electrical continuity.
- Alternatively, you can set the multimeter to ohms to test resistance.
- A functioning thermal fuse or high limit switch should read between 0 and 1 ohm.
- No continuity or incorrect resistance reading means the fuse or switch is blown.
- If the high limit switch has a reset button, press it to restore the safety feature.
- Otherwise, you have to replace the switch, like the thermal fuse that cannot be reset.
- Match the part number before buying and ensure the wiring is accurate when you install.
If you find a blown thermal fuse or broken high limit switch after a power surge, check whether or not the breaker is alright. Reset the breaker if it is tripped. Also, if you find any wire on the oven that looks burnt or damaged, you will have to replace the wiring for that component.
Customizable Modes and Settings
Many companies have a demo or showroom mode for their ovens and ranges. These ovens will not heat in this mode, although you will still be able to access the control panel and regulate the settings. The simulation demonstrates the functions, but the oven doesn’t actually heat in demo mode.
Similarly, your oven may have a few customizable modes and settings that can interfere with the unit’s heating function. The only way to detect and resolve such issues is by reading the manual or instruction booklet published by the manufacturer.
For instance, many ovens have a cooling fan. If the cooling fan doesn’t work, the oven won’t heat up. Likewise, some ovens’ thermal fuse blows during self cleaning due to high heat. Thus, such an oven won’t heat after the self cleaning cycle unless you replace the blown thermal fuse.
How To Fix
Turn off the showroom or demo mode if your oven is set to that. Also, refer to the oven manual for the standard operating practices. While most gas, electric, and dual fuel ovens share several similar features, the specific settings and troubleshooting different minor issues aren’t identical.
Dirty or Broken Gas Oven Igniter
A common reason for gas ovens not heating up is a bad igniter. Every burner in your gas oven has a dedicated igniter. These igniters won’t light the burners if they are broken or weak. The igniters should glow as they heat up to light the flames.
Also, a weak or broken oven igniter won’t open the safety valve. If the safety valve is closed, the oven won’t have any gas for the burners to ignite. Furthermore, a dirty gas oven igniter may be too weak to function properly. So, you will have to inspect the igniters to assess their condition.
Even if an igniter is glowing, it may not be working perfectly. A failing igniter might not draw the amps necessary to open the gas safety valve. Thus, you have to test the igniter for continuity before determining that the safety valve as the real culprit.
How To Fix
Here’s how you can inspect, test, and fix a dirty or broken gas oven igniter:
- Turn the oven on, select a mode, and check if the igniter for that burner is glowing.
- Check the igniters for both bake and broil burners or the bottom and top, respectively.
- If an igniter doesn’t glow, turn off the oven, unplug it, and take out the igniter.
- You may access the igniter from inside the cavity or from the rear access panel.
- Some ovens may need you to remove the rear access panel to unwire the igniter.
- If you unscrew the igniter from inside the cavity, keep a gentle tab on the wires.
- Igniters have a wire connected to the gas safety valve, so you have to unscrew that first.
- Get a multimeter once you have the igniter with its wires out of your gas oven.
- Do a continuity test or measure the resistance of the igniter to know if it is working.
- The multimeter should beep, or you’ll get a resistance reading of 0 to 1,100 ohms.
- If the multimeter reads nothing or shows OL, you have a broken gas oven igniter.
- Replace a bad igniter after matching the part number, as there are various types.
- If you have a reading, check if the igniter is dirty and clean it using a microfiber cloth.
- While you are at it, also clean the gas oven burners, as they can be sooty and grimy.
- If the igniter is clean, has continuity, and glows, you may have a bad control board.
If you haven’t handled a gas oven igniter before, watch the following video for a helpful demonstration:
Stuck or Failing Gas Safety Valve
The safety valve in a gas oven is connected to the igniter and inlet pipe. However, the valve is not inside the oven cavity, unlike the igniters and burners.
Like a regulator or shut off valve, this safety switch opens to let gas flow, but only if an igniter is hot enough to light the burners. However, a safety valve won’t open if an igniter doesn’t activate it. Also, the safety valve may be stuck, hence broken.
Furthermore, you may have a failing gas safety valve. If the valve opens and closes when your oven is preheating or cooking, the burners will go out, and the appliance will effectively stop working. Any intermittent opening and closing of the safety valve may be its fault or the igniter’s.
Suppose the igniter is unable to stay hot and draw the amps to keep the safety valve open, the burners won’t have a steady gas supply, and thus you will find your oven not heating up. Since I have already discussed the igniter, let me only talk about the gas safety valve in this section.
How To Fix
The only solution to fix a broken, failing, or intermittently working safety valve is replacing it. You will find this gas safety valve behind your oven after removing the rear access panel. Match the part number and buy a new one.
Many ovens have a dual safety valve, one for the bake burner and another for the broil. You can test the continuity of both to conclude if either is bad. A dual safety valve is often one unit, even if there are four terminals. So, you have to replace the valve even if one set of terminals is fine.
Bad Electric Oven Heating Element
Unlike gas ovens, electric ranges have fewer parts. You don’t have an igniter or gas safety valve to worry about. However, the electric heating elements aren’t as durable as you may expect. If a heating element is bad, damaged, shorted, or weak, your electric oven won’t heat up.
Like gas burners, electric oven heating elements can be unclean, sooty, and grimy. But if any of your heating elements isn’t glowing at all, then it may have structural damage. So, look for any signs of damage, such as:
- Cracks or blisters
- Discoloration
- Deformity
- Misalignment
Some ovens have a guard for the heating elements, which might make it difficult for you to see whether they are glowing or not. So, unplug the oven and remove these guards. Plug the oven in, turn it on, and check if the heating elements glow and get warm.
Select the appropriate mode to visually inspect every heating element:
- Bake: bottom element
- Broil: top element
- Roast: all elements
- Assist: rear / side elements
Warning: Always unplug an electric oven before handling the heating elements. The heating element wires are connected to a total 220V to 240V power source. Even if an oven is off at the control panel, one live wire is still connected to a 110V / 120V circuit through the wall outlet.
You should exercise additional caution if a heating element is broken. A cracked element may have a part touching the oven cavity, which can cause a short when the appliance is connected to the wall outlet. If an oven cabinet isn’t grounded through a fourth wire at its terminal block, the short will affect the entire appliance and you may get an electric shock if you touch the unit.
How To Fix
You can replace damaged wires and fix loose heating element connections. You can also clean a good heating element if the problem is only inefficient heating. However, you cannot repair a bad heating element. Test the element’s continuity if your oven isn’t heating up.
Here are the steps to access and test the continuity of an electric oven heating element:
- Unplug the oven and remove the rear access panel.
- Remove the wiring connected to the heating element.
- Use a multimeter to test continuity at both terminals.
- Inspect every heating element you suspect is bad.
- If you find continuity, the problem lies elsewhere.
- If there’s no continuity, replace the heating element.
Most electric ovens don’t require you to unscrew and take out the heating elements to test them for continuity. The terminals are exposed once you remove the rear access panel. However, you have to take apart the heating elements for inspection if you suspect structural damage.
A functioning heating element won’t heat your oven if it doesn’t have power. Since I’ve already discussed voltage, amperage, and wiring issues, the only other problems related to the heating elements working or not are the control board and temperature sensor, which I explain below.
Door, Switch, and Gasket Problems
An oven not heating up could also be due to the following problems:
- The door isn’t fully closed and sealed.
- The door switch is bad (some ovens).
- The door hinges aren’t working properly.
- The door gasket is damaged or deformed.
- The door and oven are not leveled.
- The oven door is deformed or misaligned.
An oven door switch may prevent the appliance from heating up. This switch isn’t the same as a door latch or lock. A door switch essentially completes the circuit so that the oven can start to heat. So, check your oven or the oven manual to see if it has a door switch.
The other door and gasket problems don’t stop an oven from heating. However, a leaky gasket or misaligned door will let the hot air out. Thus, your oven won’t preheat to the set temperature or take a long time to get there.
How To Fix
Choose one of these solutions, subject to your investigation:
- Level the oven and ensure the door is properly aligned.
- Replace bad hinges or a deformed door (the latter is rare).
- Get a new gasket if the current one is beyond its utility.
- Replace a faulty or broken oven door switch.
Malfunctioning Temperature Sensor
Most ovens use a resistance temperature detector. This temperature sensor has a probe inside the oven cavity. If this sensor doesn’t work properly, your oven may stop heating prematurely. A bad sensor can erroneously detect overheating or fail to read the temperature inside the oven.
If the temperature sensor touches the wall of the oven cavity, the contact can lead the sensor to detect a temperature spike when the oven isn’t really hot enough. Also, a temperature sensor may have a short. All such problems can prevent your oven from heating up.
If a temperature sensor is bad, which means it has no resistance, an oven’s heating elements may not work at all. The symptom would be similar to having a bad heating element and you won’t find the heating elements glowing.
How To Fix
Select one of the following fixes based on your diagnosis:
- Clean a dirty temperature sensor and ensure it is perfectly aligned.
- Inspect the connections and replace the wires if they are worn out.
- Test the temperature sensor’s resistance and replace it if it has none.
Watch this video to test and replace your oven’s temperature sensor:
Defective Relays or Control Board
Last but not least, your oven not heating up can be due to a defective control board.
However, if you can toggle the settings through the control panel, the entire board may not be bad. You may have bad relays on the main board preventing the critical parts from functioning.
Many ovens have more than one printed circuit board. So, your model may have a main and a mini oven control board.
Ranges also have separate control boards for the oven and surface elements. The exact control board or relay fault depends on the oven type and model.
How To Fix
You should check the schematics for your oven, whether gas or electric. The same approach applies to dual fuel, double ovens, and wall or built-in variants. Also, many ovens display an error code for control board failures. You should refer to those codes to choose a solution.
If the control board is bad, you need to get a new one. However, if one or more relays are bad, you can replace these for a fraction of the cost of the main board. I suggest replacing the relays. If that doesn’t fix the heating problem, you can get a new control board.
Chris is a Texas-based freelance writer who loves the outdoors and working in his garage. When he’s not enjoying the Texas sun, he can be found tinkering with all sorts of things in his workshop.