LG Oven Not Heating: Causes and DIY Fix Guide

If an LG oven stops heating, the problem is almost always one of three parts: the bake element (electric), the temperature sensor, or a thermal fuse. Before touching anything, cut power at the breaker—shock risk is real, and a live test can damage the control board. Start with a two-minute symptom check: if neither bake nor broil works, focus on power or the main board; if only one works, the faulty element or its wiring is the likely culprit.

Quick Triage: Three Checks Before You Open Anything

Run these in order. Each takes under five minutes and prevents buying unnecessary parts.

• Check the breaker. A 240‑volt circuit can trip on one leg, leaving the oven display on but delivering no heat to either element. Reset by flipping the breaker fully off then back on. If it trips again immediately, stop—a shorted element or wiring fault is likely. Call an electrician.
• Test bake and broil separately. Set 350°F bake. Wait 10 minutes. Look through the door glass—the bottom element should glow orange. Cancel, then run broil and check the top element.
• Neither glows → power supply, control board, or main fuse issue.
• Only one glows → that element or its wiring is failed.
• Read the error code. LG ovens display codes like F-11 (sensor out of range), F-13 (sensor shorted), or F-9 (board communication). Write it down before cutting power—it tells you exactly which circuit to test.

Early checkpoint: If the breaker holds but neither element glows, test the temperature sensor before swapping the control board. A misreading sensor can mimic a board failure and save you a $150+ mistake.

Likely Cause Buckets – Electric and Gas

Once power is confirmed and the board attempts to run (you should hear a relay click within 10 seconds of starting a bake cycle), the fault falls into one of these categories.

Component	What It Does	Failure Symptom	Quick Check
Bake element	Resistive heating coil	Element glows dimly or not at all; visible blisters or breaks	Multimeter continuity (15–40 Ω) + visual inspection
Temperature sensor (RTD)	Reports cavity temp to board	Oven under‑heats, overheats, or cycles erratically; code F-11 or F-13	Measure resistance at room temp (1080–1100 Ω for LG)
Thermal fuse	Safety cutoff if oven overheats	Oven dead on one or both functions; no continuity	Multimeter continuity mode across fuse terminals
Control board	Sends power to elements via relays	No relay click; both elements dead; code F-9 or F-21	Voltage test at element terminals (requires live test—only if comfortable)

For gas LG ovens, the equivalent parts are the bake igniter, oven gas valve, and safety thermostat. A glowing igniter that doesn’t open the valve within 90 seconds usually means a weak igniter (resistance below 40 Ω) or a stuck valve—the latter requires professional gas-line handling.

How to Test and Replace the Most Common Failed Parts

The same multimeter routine works for the bake element and temperature sensor. If you own a basic multimeter, you can confirm the failure in two minutes per part.

“Always disconnect power before servicing. Failure to do so may result in electrical shock or fire.” – LG Electronic Oven Owner’s Manual

Testing the Bake Element (Electric)

1. Disconnect power at the breaker.
2. Access the element. On most LG ranges, remove the two screws holding the oven floor, then lift the floor panel. The bake element sits in a bracket at the bottom.
3. Pull the element away from its bracket just enough to reach the two wire terminals. Don’t let the metal touch the oven chassis.
4. Set your multimeter to resistance (200 Ω scale).
5. Touch probes to each terminal. A good element reads 15–40 Ω. An open circuit (OL) means it’s burned through.
6. Check for a short to ground – one probe on a terminal, the other on bare oven metal. Any reading below infinity means the element is shorted and must be replaced.

Common mistake: grabbing the new element with bare hands. Skin oils create hot spots that cause early failure. Wear clean gloves or hold the ceramic ends.

Testing the Temperature Sensor (RTD)

1. Power off, but keep the sensor wires connected until the test.
2. Locate the sensor – a metal probe protruding into the oven cavity from the back wall.
3. Remove the two wires from the sensor (snap a photo first).
4. Measure resistance across the sensor terminals at room temperature (68–77°F). LG sensors typically read 1080–1100 Ω. A reading outside ±20 Ω indicates a faulty sensor.
5. If the sensor passes, recheck the wiring harness for corrosion at the connector to the control board. A corroded pin can mimic a bad sensor.

Testing the Thermal Fuse

The thermal fuse is a white or metal cylinder attached to the back of the oven near the vent. It blows (opens) if the oven exceeds ~400°F. Use continuity mode: a beep means good; silence means blown. Replace with an exact OEM part—generic fuses often have different temperature ratings and cause repeat failures.

Decision Point: When to Stop DIY and Call a Technician

Use this checklist to decide your next step. If you answer “no” to any of the first three items, it’s time to escalate.

• [ ] I have confirmed the oven is not receiving voltage at the element terminals (using a multimeter in AC voltage mode). If voltage is present and the element is good, the control board is likely bad.
• [ ] The error code is F-11 or F-13 (sensor-related) – these are safe to fix at home. Codes like F-9 (board communication) or F-21 (heating too slow) usually require board-level diagnosis.
• [ ] My oven is electric. If gas, the igniter glows but no flame appears within 90 seconds – the gas valve may be stuck; gas repairs often require a certified technician.
• [ ] The element shows visible damage (blistering, cracks, broken spot) – safe to replace.
• [ ] The thermal fuse is blown – I have verified the oven cavity is clear of debris and the cooling fan works before installing a new fuse, or it will blow again immediately.

Unique decision criterion: The threshold between a $30 DIY fix and a $200+ service call depends on whether your oven is gas and the igniter resistance is still within spec (40–60 Ω). A weak igniter that still glows can be swapped at home, but a non‑opening gas valve or a control board that fails to trigger the relay demands professional tools and gas‑line safety training.

Step-by-Step: Replace a Bake Element (Electric Focus)

This workflow covers the most common electric fix. The same logic applies to a sensor or fuse swap.

1. Remove power at the breaker. Confirm the display is dark.
2. Access the element. On most LG ranges, remove the two screws on the oven floor and lift the floor panel.
3. Disconnect the old element. Note wire colors (usually red and black). Unscrew wire nuts or unclip connectors.
4. Inspect the mount. Check for melted insulation near the terminals—if the old element shorted, the wire harness may be damaged. Replace the harness if needed.
5. Install the new element. Push the wire terminals onto the new element posts. Polarity usually isn’t critical for bake elements, but match the connector shape if there’s one.
6. Check for clearance. Ensure the element doesn’t touch the oven floor or side walls. Secure with bracket screws.
7. Restore power and set to 350°F bake. The element should glow within 30 seconds.
8. Success check: Oven reaches set temperature within 10–15 minutes (use an oven thermometer for accuracy). If it doesn’t heat, recheck wiring and test voltage at the element terminals. If 240 VAC is present but no heat, the element is defective. If no voltage, test the temperature sensor first—a misreading sensor can trick the board into withholding power. That test can save you $150+ on an unnecessary control board.

Friction point: If the oven still fails after confirming a good element and sensor, the root cause is almost always the control board. Before ordering, check for secondary thermal fuses behind the rear panel—some LG models have a second fuse on the control board that blows if the oven overheats during self‑clean.

Gas LG Oven Specifics

Gas models share the same control board design but use different heating hardware. The most common failure path:

• The oven igniter glows but never opens the gas valve → measure igniter resistance; below 40 Ω means it’s too weak to open the valve → replace igniter.
• The igniter doesn’t glow at all → check the safety thermostat (cutoff switch) and the control board output. For a broader look at igniter and valve issues, see the guide on troubleshooting lg oven problems and solutions.

Safety warning: If you smell gas faintly, stop immediately, open windows, and call a professional. Do not attempt to disassemble the gas valve yourself. A stuck valve can also cause the igniter to fail prematurely; if the same igniter blows twice within a year, have a technician inspect the gas supply line and valve assembly.

Preventing Future Heating Failures

Two factors accelerate most heating failures: blocked airflow and aggressive self‑cleaning cycles. Self‑clean mode blasts the oven at 800°F+, stressing elements and thermal fuses. Limit self‑clean to once a year, and never let the oven cool rapidly after a cycle—a cracked element is often the result.

Clean accumulated grease and food debris from the oven floor and around the element mounts. A dirty cooling fan restricts airflow and can blow the thermal fuse prematurely. For a full maintenance schedule, check our guide on essentials for caring for lg oven.

If the same component fails twice within a year, re‑examine root cause: inadequate voltage (loose neutral wire), a failing control board that over‑powers the element, or a gas valve that sticks partially open, poisoning the igniter. An appliance tech can verify supply voltage and board logic—a diagnostic service call is often cheaper than buying two elements and a sensor. For broader guidance across multiple LG appliance failures, the troubleshooting lg appliance problems and solutions page covers common threads.

Understanding whether the issue is a dead element, faulty sensor, or blown fuse lets you decide if a $15 part swap is enough or if professional diagnosis is needed. When in doubt, the error code on the display and a quick multimeter check will tell you more than any guess.