Samsung Oven/Range Error Code C-21 — Gas Igniter Fault / No Flame Detected
What this means
The C-21 error code appears on Samsung gas ranges when the control board opens the gas valve but does not detect a flame within the expected ignition window. The most common cause is a weak or cracked hot surface igniter that doesn't draw enough current to open the gas safety valve. A faulty gas valve, clogged burner orifice, or disrupted gas supply can also be responsible.
Alternate codes: C21
Step-by-step fix
4 stepsVerify the gas supply
Check that the gas shutoff valve behind or beneath the range is fully open. Try lighting a stovetop burner to confirm gas is flowing to the appliance. If no stovetop burners light, the issue is upstream — not the oven igniter.
If you recently had plumbing or gas work done, a valve may have been left partially closed.
Observe the igniter glow
Remove the oven racks and the oven floor panel (if removable) to expose the bake burner and igniter. Turn on the oven and watch the igniter. It should glow bright orange/white within 30–90 seconds. If it glows dim orange or doesn't glow at all, the igniter is weak or dead.
A healthy igniter draws 3.2–3.6 amps. Below about 3.0 amps it cannot open the safety valve, even if it still glows.
Test the igniter with a multimeter
Turn off the gas and unplug the oven. Disconnect the igniter wires. Measure resistance across the igniter — a good igniter reads between 40–400 ohms depending on the model. An OL reading means it is completely open and must be replaced.
Even if resistance is in range, a weak igniter can fail under load. If it glows but never triggers the gas valve, replace it.
Replace the igniter
Remove the two mounting screws holding the igniter bracket near the burner tube. Carefully disconnect the old igniter and connect the new one — do not touch the new igniter element with bare hands as skin oil can cause hot spots. Reassemble the oven floor panel, reconnect power and gas, and run a bake cycle to confirm ignition.
Handle the new igniter by its ceramic base only. Wear clean gloves or hold it with a cloth.
When to call a professional
If the igniter glows properly and draws adequate amperage but the gas valve still doesn't open, the gas safety valve itself may be defective. Gas valve replacement should be performed by a licensed technician due to the risk of gas leaks.
Related error codes
The oven temperature sensor (thermistor) has an open or shorted circuit.
Moderate Fix · 30–60 minutes
The oven's main control board and display board cannot communicate.
Advanced Fix · 30–60 minutes
The oven has exceeded its maximum safe operating temperature.
Advanced Fix · 30–60 minutes
Information compiled from manufacturer service manuals, official troubleshooting documentation, and appliance repair industry resources. This guide is for informational purposes only — always consult a qualified technician for complex repairs.
Learn more about our sourcesParts you may need
Oven Igniter (Bake)
Part #DG94-01012A · $20–$45
If igniter does not glow bright or reads OL on multimeter
Gas Safety Valve Assembly
Part #DG94-01441A · $80–$150
Only if igniter is good but valve doesn't open — professional install recommended
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