LG Refrigerator Not Cooling But Freezer Works

When the freezer works, but the fresh food portion doesn't, there are several things to check right away.

Make a point of checking the settings. Someone else may have mistakenly adjusted them. Sometimes, in trying to adjust one setting, we can accidentally reset another.

Make a point of checking the refrigerator (fresh food) compartment door seals. Air leaks will cause poor cooling. One sign of this will be condensation inside the refrigerator. The freezer will be unaffected.

Too much stuff in the refrigerator can block the vents that bring the cold air from the freezer. Usually, these vents will be located at the rear of the unit. Make sure you pull food away from the refrigerator walls so that the vents are clear.

In refrigerators with an evaporator in the fresh food compartment, blocking the vents can lead to ice forming on the evaporator coils, which will then cause higher temperatures in the fresh food compartment from poor air circulation. Moving air removes heat and keeps things cool.

Unplug the fridge for 1 minute, then plug it back in. You will want to observe it the temperature in the fresh food compartment starts to lower to proper levels. This won't cure things like an ice buildup or faulty components, but it may restore a fridge with a program glitch.

If these things don't help, go to the first cause.

A buildup of ice on the evaporator will cause uneven temperatures. The freezer may still be cold, but the fresh food compartment may start to warm up. If you have a dual evaporator refrigerator, with one in the freezer and one in the fresh food compartment, go to the evaporator in the fresh food compartment. The fresh food evaporator controls that portion, so you don't need to check the freezer unit.

To check on this, you will need to remove the evaporator cover in the rear of the compartment. If it doesn't come off easily, don't force it. You can try to run a Forced Defrost Cycle, but it might be easier to just manually defrost the unit.

• Use a steamer to remove ice on the evaporator coils. Do not use a heat gun, and avoid a hairdryer, as you can inadvertently warp plastic components unless you use great care. Further, a steamer is faster.
• If you don't have one, use large bowls of hot water placed in the bottom of the compartment.
• In any event, make sure your condensate drain tube is not plugged. This can be a cause of the buildup. See LG Refrigerator Leaking Water for more information.

When you do these checks in the freezer (single evaporator), check the freezer door seals as well. Bad door seals will lead to excessive frost, which can turn into ice on the evaporator. Then the refrigerator doesn't get as cool because the evaporator fan doesn't circulate air through a chunk of ice.

If there is no ice buildup, go to the next step.

The damper is a flap that controls the airflow between the freezer and the fresh food compartment. It allows cold air from the freezer into the fresh food area as needed to maintain the temperature. Skip this step if your refrigerator has an evaporator in the fresh food section. It won't have a damper.

Otherwise, the issue may be that the damper is refusing to open. You can check the damper motor for proper values. Here is a guide that goes into this. Occasionally it may have become iced.

If the damper checks out okay go on to the next item.

A faulty evaporator fan in a standard single-evaporator fridge will affect the freezer's performance, but you may not immediately notice it and first experience poor cooling in the fridge while the freezer seems to work. The performance of the freezer will be affected, but you should check in any case.

• When you open the fridge door, you should hear the fan run (some units will shut off the fan when the refrigerator door is opened).
• If you're not sure in that case, a quick check is to simulate the door closing by pushing the door button or placing a magnet near the door closing sensor located near the top hinges of the doors.
• If the fan turns on, it's good.

With a two-evaporator model, If the fresh food compartment evaporator fan fails, the temperature there will rise quickly, while the freezer will be unaffected.

• Open the door and check for airflow
• If none, you will want to check that fresh food compartment fan by removing the evaporator cover there and checking the condition of the evaporator and fan.
• You can use the door check described above first if you don't have any airflow.

A continuity check in either case is usually pointless, as fans on these newer models use BLDC motors, which generally have small circuit boards inside the motor. You can't readily measure winding resistance directly. You can see that they turn smoothly by hand and spin when the door is shut. (Use a phone camera to take a video inside the compartment)

If the fan checks ok, go on to the next item.

The refrigerator monitors the temperature inside the fresh food compartment with a device called a thermistor. The resistance of the thermistor is what is monitored by the main control board. If the thermistor is out of spec, the control board will sense the temperature incorrectly.

• At 20°C (77°F), the resistance is around 10-11kΩ for most LG refrigerator compartment thermistors.
• A quick procedure is to power down the fridge and then unplug and re-plug, in turn, each connector on the control board. Then try starting the fridge again.
• The thermistor resistance on the refrigerator is best checked at the control board. This allows you to "see" what the control board is seeing.

A service manual for your model is the best guide for which connection to check on the board. Here's an example page showing the wires to test for the fresh food (refrigerator) thermistor. This is from a somewhat older LG French door model (LFX25973)

The page actually states that if you have an open circuit, you have to replace the refrigerator. Kind of drastic, but the issue is that the wiring harness for the thermistor is buried in the insulation of the fridge. So, if there's a broken wire, there's almost nothing you can do about it. See below in Help For a Faulty Thermistor for more on this and other checks to run.

The following causes are likely beyond the usual DIY capabilities but are listed for completeness and for those willing folks who press on.

If the 3-way valve is faulty, it may be possible to replace the coil that drives the valve, but this is often impossible, and only replacing the valve body will work. This is beyond a DIY repair.

The control board may be at fault, but the diagnostic tests to verify this are complex and beyond the scope of this document. There will likely be other malfunctions.

Since thermistors do fail, you should make an extra check at the thermistor location itself, especially if you read an open or a short. You can remove the thermistor from the small cage or grille that holds it. This will allow you to access a pigtail attached to the thermistor. You can then isolate the thermistor and see if the defect is in the thermistor or in the refrigerator's wiring.

If you make this check, you will need to cut the wires to the thermistor. You will then measure the thermistor directly. If it is in spec, but the control panel reading was open, you have an internal wiring problem that will be essentially impossible to fix. The same goes for a correct reading at the thermistor but a short reading at the control panel.

If your thermistor reads shorted or open itself and that matches the control panel reading you got, you may choose to replace the thermistor. You will have to make waterproof splices in the wiring when you connect the new thermistor since it will be subject to moisture.