When yourLG ovensuddenlyfailsto heat and cook your food, displaying a cryptic “F9” on its display screen, it can be immensely frustrating and concerning.
However, do not despair—thiserror code, while preventing you from using your oven, points to definable issues that can likely be corrected with some targeted troubleshooting.
Essentially, the F9 code conveys that during the oven’s important preheating process, where it brings itself up to the desired cooking temperature, adequate heating failed to occur.
This signifies inner components involved in heat generation or regulation could be malfunctioning.
By calmly investigating several oven components and functions that commonly falter, triggering the F9 code, you should be able to pinpoint the true issue.
We will walk through checks involving elements like igniters, gas valves, etc.
What Does F9 Mean on a Stove?
Table of Contents
The F9 error code is a common problem with gas and electric ovens. This error code typically indicates a failure to properly regulate and maintain baking temperatures.
On LG gas oven models, the F9 code means that the oven was unable to exceed 150°F degrees after the initial 5-minute preheating sequence.
On LG electric ovens, the F9 code could signal issues with components like the temperature sensor, relay control board, thermostat, or damaged heating elements – all causing irregular heat patterns.
Basically, for both gas and electric models, the F9 code implies that the oven is not getting hot enough, fast enough due to problems with parts or components that are crucial for safe, consistent heating.
If the F9error codeis not quickly addressed, it poses safety and operational risks. For example, gas ovens may have dangerous gas leaks leading to fire hazards and explosions.
While the electric models can short circuit due to overheating elements, and can also lead to fire hazards as well. In addition, the oven circuitry and heating components could be further damaged, requiring expensiverepairsdown the line.
How to Fix the F9 Error Code LG Gas Oven
Seeing that intimidating F9 show up on yourLG gas oven display may feel unsettling but have hope this is a common code that can typically be resolved with some simple troubleshooting. Before you call that repairperson (qualified technician), try a little DIYrepairmagic.
Think of an F9 error as your oven crying wolf – it’s saying there’s not enough heat, but it’s likely just a spark or gas flow issue, not a major failure. With a few handyperson tricks up your sleeve, you can coax more life out of thisapplianceand avoid an expensive visit from atechnician.
Rule number one is always to disarm before you dive in:switchoff breakers and gas valves so you have a safe workspace.
Have you done that? Then it’s detective time!
1. Inspect the Igniter
The igniter is responsible for sparking and lighting the gas burner by heating to extremely high temperatures.
To access the igniter, do the following:
- First, carefully remove the oven door by unlocking the hinge locks and pulling the door straight out.
- Next, take out all oven racks and clear the oven interior. Then, unscrew and remove the bottom access panel.
- Detach the burner shield by removing thescrews, then lift off the shield to expose the igniter at the back near the burner.
- Inspect the igniter for any cracks or damage. Use amultimeterto check the igniter resistance, which should normally fall between 40-200 ohms. If outside this range, the igniter will need replacing.
To replace the igniter:
- First unscrew the mountingscrewsholding it in place, then disconnect the attachedwire connector– you may need to remove the bottom drawer for access.
- Remove the old igniter and install the new one, tightening the mountingscrewsfirmly.
- Reconnect thewire connector. Replace the burner shield, access panel and allscrewssecurely.
- To refit the oven door, slide it back onto the hinges properly then lock it into position. Insert all oven racks.
- Finally, restoregas supplyand electricity before testing operation.
2. Check the Gas Valve
The gas valve controls the flow of gas in the oven. If the gas valve is defective, it can disrupt supply downstream to the igniter and burner.
To check or inspect the gas valve, do the following:
- Remove the lower back access panel by unscrewing the securingscrews.
- Locate the gas valve near thegas supplylines.
- Note where the bake and broil wires are connected, then disconnect them.
- Unthread the nuts securing thegas supplytubes to the valve.
- Use amultimeterto check the voltage while operating the oven. If the voltage is not present, then you’ll have to replace the gas valve.
To replace yourfaulty gas valve, continue with the following steps:
- Remove thescrewsholding the valve to theback paneland pull the valve away to remove it.
- Insert thegas supplytubes into the new valve and position it on the mounting tabs.
- Replace the securingscrewsand reattach the wire terminals and bake/broil wires correctly.
- Replace the lower back access panel.
- Turn thegas supplyand power back on. Then test the oven’s functions to ensure proper gas flow.
3. Inspect Relay Board
The relay board controls the voltage for oven components like the igniter. If the relay board gets damaged, it can prevent proper ignition.
To inspect the relay board, do the following:
- Pull the oven away from the wall to access the back.
- Remove thescrewssecuring therear paneland take it off. You should find the relay board at the top right behind the oven.
- Check the board and attached wiring for visual damage.
- Use amultimeterto checkrelaysand replace them if found to be faulty.
To replace faulty relay boards, do the following:
- Disconnect allwiring harnessesattached to thefaulty relay board. Remove the mountingscrewsto detach the old relay.
- Align and insert the new relay board into the control assembly.
- Replace the mountingscrewsto secure it and reconnect allwiring harnessesto the correct terminals.
- Replace therear access paneland push the oven back into place.
- Test oven functions to ensure that the new relay board works properly.
Related:Gas Oven Not Heating: 6 Easy Ways To Fix The Problem Now
How to Fix F9 Error Code LG Electric Oven
If your LGelectric ovenis displaying an F9error code, it means that there’s a problem with the oven and that problem has made it unable to reach the target 150°F temperature after 5 minutes of preheating.
As earlier stated, for electric ovens, the F9 error code problem lies within failed heating components. Several components could be responsible, and this section is all about inspecting, replacing, and testing those components.
But before we go on with that, make sure toswitchthe oven’scircuit breakeroff in the main electrical panel and unplug the oven from the wall outlet.
Without further ado, let’s take a look at some of the components that could be behind the F9error codeon your LGelectric oven:
1. Inspect the Control BoardandRelays
Thecontrol boardandrelayscoordinate the oven’s functionality by communicating the required temperature settings to other components.
To inspect thecontrol boardandrelays, do the following:
- Remove the back access panel to expose the boards.
- Check boards and wiring for burn marks indicating short-circuiting.
- Use amultimeterto testrelaysand other control circuits for continuity. If there’s any damaged board, replace them.
To replace the damaged boards and replays in yourelectric oven, do the following:
- Thecontrol boardis located at the top of the oven cavity.
- Disconnect allwiring harnessesand connectors attached to the oldcontrol board.
- Remove the mountingscrewsand detach theold board.
- Align and insert thenew boardinto the oven cavity.
- Replace the mountingscrewsto secure it in place & reconnect allwiring harnessesand connectors.
If it’s the relay you need to replace, do these instead:
- Remove any faultyrelaysfrom thecontrol board.
- Insert newrelaysof the same type into the correct sockets.
Once you are done, replace the upper access panel and push the oven back into place. Restore the power supply and test the oven to ensure the newcontrol boardandrelaysyou installed work properly.
2. Check the Oven Sensor
The oven sensor monitors baking temps. If the oven sensor becomes defective, it can send inaccurate readings to thecontrol boardtriggering the F9 code.
To check the oven sensor in your LGelectric oven, do the following:
- Pull the oven away from the wall to access the back.
- Remove thescrewsfrom therear access paneland take it off.
- Locate the sensor. It is usually found at the back of the oven cavity.
- Detach the wiring and inspect for damage.
- Use amultimeterto test for continuity. If itfailsthe test, you’ll have to replace it.
To replace a faulty oven sensor, do the following:
- After detaching the wiring, unscrew or loosen any retainingclipsorbracketssecuring the faulty sensor.
- Pull the old sensor out of the oven cavity.
- Insert the new sensor into the opening and secure it in place with the retainingclipsorscrews.
- Reattach any wiring to the correct sensor terminals.
- Replace therear access paneland push the oven back into place.
- Restore the power supply and test the oven functions to ensure the new sensor works fine.
3. Examine the Heating Element
The baking/broiling element at the bottom/top of the oven transforms voltage into heat. So, if there are continuity issues, it means that there’ll be no heat.
To inspect the heating element in yourelectric oven, do the following:
- Open the oven door fully and lift up the hinge locks to detach the door from the oven.
- Pull out all oven racks and set them aside.
- Remove thescrewssecuring the bottom access panel and lift it off.
- Disconnect the wires from the heating element terminals and unscrew the retainingbracketsat the back of the oven cavity.
- Carefully pull out the heating element before inspecting the element’s wiring and coil visually for hot spots/damage.
- Use amultimeterto check if the element’s resistance is in the normal range. If it falls off the normal range, then you’ll have to replace it.
To replace a faulty heating element, do the following:
- Insert the new heating element into the oven cavity opening.
- Replace the retainingbracketsandscrews. Reconnect wires to the element terminals.
- Replace the oven racks and door. Then replace the bottom access panel.
- Restore the power supply and test to see if the new heating element works properly.
4. Inspect the ThermostatandThermal Fuse
Oven overheating andself-cleaningmalfunctionsare capable of damaging components like thethermostatandthermal fuse.
Thethermostatandthermal fuseplay an important role in regulating temperature. So if they become defective, they can trigger the F9error code.
To check thethermostat, do the following:
- Turn the oven power off from the main electrical panel.
- Remove therear access panelto locate thethermostat.
- Detach the wires and metal retaining tab from thethermostat.
- Visually inspect thethermostatfor damage like melting, and use amultimeterto test it for continuity.
- If itfailsthe test, you’ll have to replace the faultythermostat.
To check thethermal fuse, do the following:
- Similarly, disconnect all power to the oven.
- Locate thethermal fusewiring in the rearcontrol panel.
- Remove the fuse holder and check the fuse continuity using amultimeter.
- If the fuse is blown, you’ll have to replace it with a new one of equal specs.
After replacing thethermal fuse, you can now test to see if your oven now works correctly.
Related:Electric Oven Not Heating Up: 6 Easy Ways To Fix It Now
How to Reset LG Gas/Electric Ovenafter Fixing F9error code
Now that the troubleshooting is done, it’s time to walk you through the proper way to get your oven reset and back in working order:
- Make sure that the oven andcircuit breakersare switched off before resetting.
- Locate thecircuit breakerconnected to the oven andswitchit all the way to the “Off” position.
- Unplug the oven from the outlet orswitchoff if the outlet is hard-wired.
- Wait for 1-2 minutes before plugging the oven back in orswitchthe outlet back on. This gives time for the electrical components in your oven to reset.
- Flip thecircuit breakerback to the “On” position.
- For gas ovens, then the gas valve back to the open/on position.
Now we’ll want to test basic functions.
To test your LG oven, do the following:
- Set the oven to bake at 350°F and verify it heats up. Use an oven thermometer placed inside to double-check the temperature reading. Good news? Celebrate with cookies!
- If the oven doesn’t turn on or get up to temp, recheck yourrepairsteps.
One last thing — the oven temp can drift afterrepairs. Not to worry! Your owner’s manual will walk you through adjusting and calibrating it.
There you have it! With some simple safety checks and reset steps, yourLG ovenwill be back doing what it does best – turning out mouthwatering meals that your family and friends will love.
Conclusion
The LG F9error codecan be frustrating, but resolving it is often straightforward. For gas ovens, inspect the igniter, gas valve, and relay board, replacing any faulty parts.
On electric models, examine thetemperature sensor,control board, heating element,thermostat, andthermal fuse.
After replacing damaged components and safely resetting the oven, recalibrate if needed to restore precise baking temps.
With some targeted troubleshooting, you can get yourLG ovenback up and running for all your cooking needs.
Reference: LG F9 Error Code Support
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Adrian Simmons( Licensed Appliance Repair Expert )
Adrian is an ISCET licensed professional that has completed the National Appliance Service Technician Certification Exam and has the expertise to diagnose and repair any appliance. He is well-versed in the latest technologies and techniques and is always up-to-date on the latest industry standards.