LG Oven Error F21

⚡ Quick Answer: The LG oven error code F21 indicates a potential malfunction within the heating element, which may lead to improper heating or unusual sounds during o... ✅ DIY Fixable

What Does Error F21 Mean?

The LG oven error code F21 indicates a potential malfunction within the heating element, which may lead to improper heating or unusual sounds during operation. To troubleshoot, first ensure the oven door is fully closed and then power cycle the unit by disconnecting it from the electrical supply for 1–2 minutes before restoring power. If the error persists, further inspection of the oven sensor wiring and control connections may be necessary.

Possible Causes

  • Heating Element
  • Wiring Issues
  • Control Board Malfunction

How to Fix Error F21

DIY Fix General basic checks and reset

  1. Ensure the oven door is fully closed.
  2. Turn off the oven and disconnect power at the wall or circuit breaker.
  3. Wait at least 1–2 minutes and restore power.
  4. Observe if the F21 code returns when powering on.

Technician Only Inspect oven sensor wiring and control connections

  1. Check wiring harnesses to the temperature sensor and control board for loose or damaged connectors.
  2. Using a multimeter, verify continuity and proper resistance of the temperature sensor against manufacturer specifications.
  3. Inspect control board connectors for signs of burn marks or corrosion and reseat or replace as needed.

Parts needed: temperature sensor, wiring harness, control board

🛑 When to Call a Pro:
  • If the error persists after power cycling.
  • If any wiring appears burnt, frayed, or damaged.
  • If temperature readings from the oven sensor do not fall within expected ranges.

Next step

Choose the next step for F21

Confirm the diagnosis before ordering. An error code can identify the system involved, but it does not prove that a specific part has failed.

Other parts options

Check related components first; use model search as a fallback.

Possible related component

Wiring Harness

Connects controls, sensors, motors, and other electrical components inside the appliance.

$20 - $120 · Medium · 30-90 mins

Check fit & price
Possible related component

Main Control Board

The central brain of the appliance that controls all components, cycles, and timings.

$120 - $280 · Medium · 20-40 mins

Check fit & price
Model number required

Model-compatible Oven parts

Enter the complete model number to browse compatible replacement parts. This is a model-based parts search, not a diagnosis that a specific component failed.

Find a part that fits my model

Affiliate disclosure: As an Amazon Associate I earn from qualifying purchases. We may earn a commission from other qualifying purchases or service requests made through links on this page, at no additional cost to you. Recommendations are based on repair relevance, not commission rate.

Optional routine care

Maintenance supplies

These products support cleaning or routine upkeep. They are separate from the possible repair components above and are not claimed to fix this error code or symptom.

Maintenance supply

Non-Scratch Cooktop Cleaner

A routine surface-care product. Confirm that it is approved for the specific glass, ceramic, enamel, or stainless finish.

View maintenance supply
Diagnostic tool

Oven Thermometer

A diagnostic aid for comparing cavity temperature during a controlled check. It does not prove which internal component has failed.

View maintenance supply

Affiliate disclosure: As an Amazon Associate I earn from qualifying purchases. Recommendations are based on routine-care relevance, not commission rate.

Technical Specifications

note The previous model-independent part specification was removed. Verify the full model number and diagnosis in the manufacturer's official parts catalog before ordering.
part_number None

Common Questions

What does F21 error mean on LG oven?

F21 indicates a malfunction in the heating element, resulting in improper heating.

Can I fix LG oven F21 error myself?

Yes, start by ensuring the oven door is closed and power cycling the unit.

How much does it cost to fix F21 error?

Repair costs vary; expect moderate costs for wiring or sensor, and higher for control board replacements.

When should I call a technician for F21?

Call a technician if the error persists after a power cycle or if wiring appears damaged.

Sources & References

Data last verified: 2026-07-31

User Comments (0)

Share your experience or solution below.

Be the first to comment!

Call Local Repair Provider +1 (888) 217-6318