An oven not preheating is one of the most common appliance complaints in 2026, and the cause is almost always one of five specific components. Some fixes take under 30 minutes with basic tools; others require component-level diagnosis. This guide ranks solutions from most likely to least likely so you can work through them efficiently without unnecessary parts purchases.
5 Common Causes for Oven Not Preheating
1Failed Bake Element
The bake element is the large coiled heating element mounted to the floor of an electric oven. Over time — and especially after power surges or extended use — the element’s resistance wire can crack, blister, or burn through entirely. When it fails, the oven either won’t heat at all or heats only partially because the broil element alone cannot maintain temperature.
Care Plan
- Disconnect power. Turn off the oven at the control panel, then flip the dedicated circuit breaker to the OFF position. Confirm the oven is completely de-energized before proceeding.
- Visually inspect the element. Open the oven door and examine the bake element along its full length. Look for visible cracks, burn holes, blistering, or a section that appears darker or melted compared to the rest of the element. A burned-through element is often a definitive visual diagnosis. Wear gloves when handling a burned or damaged element — carbon deposits from an arc failure are electrically conductive and should not be touched with bare hands.
- Test with a multimeter (if no visible damage). Set your multimeter to the resistance (Ω) setting. Remove the element (see Step 4 below) and touch one probe to each terminal. A functioning element will show continuity (a numeric reading, not “OL”). The exact resistance value varies by wattage and manufacturer — consult your oven’s OEM service documentation or the element’s model spec sheet for the expected reading. Any “OL” (open loop / no continuity) reading confirms the element has failed.
- Remove the element. Unscrew the two or four mounting screws securing the element to the oven back wall. Before disconnecting any wires, photograph the terminal connections clearly with your phone. Gently pull the element forward only 4–6 inches — enough to access the wiring terminals without putting tension on the wires. Important: Do not let the wire connectors slip back through the hole in the oven rear wall. If they retract, you may need to remove the back panel to retrieve them. Squeeze the wire connectors and pull them straight off the terminals.
- Install the new element. Connect the wires to the new element’s terminals in the same configuration as photographed. Feed the wire carefully through the rear wall opening, seat the element, and reinstall the mounting screws. Restore power at the breaker, run the oven to 350°F, and confirm it preheats fully. If the oven still won’t preheat, proceed to Cause 3 (if you have an electric oven — Cause 2 applies only to gas ovens).
Common Mistakes
- Forgetting to photograph the wire terminal connections before disconnecting them, leading to incorrect reassembly.
- Allowing the wire connectors to slip back through the rear wall hole during removal — always hold the wires while disconnecting terminals.
2Weak or Cracked Igniter (Gas Ovens Only)
In a gas oven, the igniter serves two functions: it glows hot enough to ignite the gas, and it must draw sufficient current to generate enough heat to open the thermally-activated safety gas valve. If the igniter is too weak to reach this threshold, the valve stays closed and gas never flows — the oven will appear to try to light but never actually heat up. Igniters degrade gradually, so the oven may work intermittently before failing completely.
Care Plan
- Shut off both gas and power. Turn the gas supply valve at the appliance to the OFF position (the handle should be perpendicular to the gas line). Then turn off the oven’s dedicated circuit breaker. Both must be off before any component access.
- Access the igniter. Remove the oven racks, then remove the oven floor panel (typically held by two screws at the rear). The igniter is mounted next to the burner tube at the back of the oven cavity. It is a small, fragile ceramic-and-metal component — handle it gently to avoid cracking the silicon carbide element.
- Visually inspect the igniter. Look for visible cracks in the igniter body, which are an immediate sign of failure. A hairline crack is enough to render the igniter non-functional.
- Test current draw (Advanced — if uncertain, skip to replacement). This test requires restoring electrical power only — the gas supply must remain off. Do not reach inside the oven cavity while power is live. Using a clamp meter set to AC amps, clamp around one of the igniter wire leads at the external wire harness connector (outside the oven cavity). Restore power at the breaker and set the oven to Bake at 350°F. Read the current draw on the clamp meter, then immediately turn off the breaker again. A reading above 3.2 amps indicates a functioning igniter for most common gas valve assemblies. Note: The 3.2-amp threshold is the minimum for many common gas valves (including those used in GE and Frigidaire ranges) — consult your oven’s service manual for the specification applicable to your specific model, as thresholds vary by manufacturer and valve assembly. If you are not comfortable performing live-circuit measurements, skip this step and proceed to replacement based on age and visual symptoms alone.
- Replace the igniter. With power and gas both off, disconnect the igniter wire harness connector (usually a plug-type connection near the rear of the oven floor). Remove the one or two mounting screws holding the igniter to the burner bracket. Install the new igniter, reconnect the harness, and reinstall the floor panel and racks. Restore the gas supply, restore power, and test the oven. If the oven still fails to preheat, proceed to Cause 3. For gas-specific warning signs that require immediate professional attention, see the When to Call a Pro section of this guide.
Common Mistakes
- Touching the silicon carbide igniter body with bare fingers — skin oils can create hot spots that crack the element prematurely. Handle only by the mounting bracket or wiring.
- Restoring the gas supply before confirming all connections are secure and the floor panel is reinstalled.
3Faulty Temperature Sensor
The temperature sensor — also called an RTD (Resistance Temperature Detector, a type of sensor whose electrical resistance changes predictably with temperature) or oven thermistor — is a thin probe mounted inside the upper rear corner of the oven cavity. It sends a continuous resistance reading to the control board so the board knows the actual oven temperature. If the sensor fails or drifts out of calibration, the control board receives incorrect data and may stop energizing the heating element entirely, or it may heat the oven to the wrong temperature.
Care Plan
- Disconnect power. Turn off the oven at the control panel and flip the circuit breaker to the OFF position.
- Locate the sensor. Open the oven door and look in the upper rear corner of the oven cavity for a thin metal probe (typically 2–4 inches long) mounted with one or two screws. It connects to a wire harness that runs through the rear oven wall.
- Test sensor resistance with a multimeter. Set your multimeter to the resistance (Ω) setting. Without removing the sensor, disconnect the wire harness connector at the rear of the probe. Touch the multimeter probes to the two sensor terminals. At room temperature (approximately 70°F), the most common RTD-type oven sensors read approximately 1,000–1,100 ohms. Note: This range applies to the most common RTD-type sensors used by major brands — verify the expected resistance for your specific model in the owner’s manual or OEM service documentation, as some manufacturers use sensors with different nominal resistance values. A reading significantly outside your model’s specified range, or an “OL” reading, confirms a failed sensor.
- Remove and replace the sensor. Before disconnecting the harness, hold the wire connector firmly so it cannot retract through the rear wall. Remove the mounting screws and gently pull the sensor forward far enough to access the connector. Disconnect the old sensor. Feed the new sensor’s wire harness through the rear wall opening before mounting the new probe — this prevents the wire from retracting into the wall cavity. Mount the new sensor with the original screws and reconnect the harness.
- Restore power and test. Set the oven to Bake at 350°F and allow it to complete a full preheat cycle. Use an independent oven thermometer placed in the center of the cavity to verify the actual temperature matches the set temperature within ±25°F. If the oven still won’t preheat, proceed to Cause 4 (control board).
Common Mistakes
- Releasing the wire harness connector before securing it, allowing it to retract into the rear wall cavity (retrieving it may require removing the back panel).
- Purchasing a replacement sensor by appearance alone — always verify the part number against your oven’s model number, as sensors with different resistance profiles are not interchangeable.
4Defective Control Board
The control board (sometimes called the ERC or Electronic Range Control) is the command center of your oven. It uses relays—mechanical switches—to send high-voltage power to the heating elements. Over time, these relays can wear out or the solder joints on the board can crack due to the extreme heat cycles of the oven. If your elements and sensors test fine, but the board isn’t “clicking” to engage the heat, the board has likely failed.
Care Plan
- Disconnect power. Turn off the dedicated double-pole breaker. Confirm the unit is de-energized with a non-contact voltage tester before touching any wiring.
- Access the board. Remove the upper back panel of the range to expose the rear of the control board.
- Visual Inspection. Look for visible burn marks, melted plastic, or “scorched” smell on the board. Look closely at the relay terminals (the larger black boxes) for cracked solder joints or black soot.
- Replace the board. Photograph the wiring connections—this is vital, as there may be many identical-looking wires. Unplug the connectors, unscrew the old board, and install the new OEM-spec unit ($100–$500). Restore power and test the preheat cycle.
Common Mistakes
- Misdiagnosing the board. Control boards are expensive. Always test the bake element and sensor first, as they are much cheaper and more likely to be the problem.
- Wiring errors. If you don’t have a clear photo to reference, a single misplaced wire can short out the new board or prevent the oven from heating.
5Tripped Thermal Fuse
The thermal fuse is a one-time safety device that cuts power to the heating circuit if the oven’s internal temperature exceeds a safe threshold (often after a self-cleaning cycle or if the cooling fan fails). If this fuse blows, the oven may power on and the display may work, but it will never send power to the heating elements.
Care Plan
- Disconnect Power. Turn off the circuit breaker and confirm the unit is de-energized.
- Locate the Fuse. On most 2026 models, the thermal fuse is located on the back panel of the oven or near the control board housing. Consult your model’s service diagram.
- Test for Continuity. Set your multimeter to the continuity (beep) or resistance (Ω) setting. Touch the probes to the two terminals of the fuse. A functioning fuse will beep or show near-zero resistance. An “OL” reading confirms the fuse is blown.
- Identify the Root Cause. Fuses rarely blow for no reason. Check that the cooling fan (if equipped) is spinning freely and that the oven’s rear vents are not blocked.
- Replace the Fuse. Swap the blown fuse for an exact OEM-spec replacement. Never bypass this fuse with a wire, as it is a critical fire-safety component.
Common Mistakes
- Bypassing the fuse. “Jumping” the fuse to test the oven is dangerous. If the oven has a runaway heating issue, bypassing the fuse removes the only safety mechanism preventing a fire.
- Ignoring the cooling fan. If your oven has a cooling fan (common in wall ovens), a failed fan will cause the new thermal fuse to blow again within minutes.
