Liebherr Refrigerator Error Code BT031

Freezer Air Sensor Error (Compressor May Run Continuously)

When your Liebherr refrigerator suddenly flashes Error Code BT031, it’s more than just a random number on the display. This code is your appliance’s way of telling you there’s a problem with the freezer compartment air sensor. In plain language, the “thermometer” that reads the air temperature inside the freezer is faulty or out of range, and the control board doesn’t trust its signal anymore.

Because of that, the refrigerator may react in a weird way: the compressor can run almost all the time, the freezer may get extremely cold, or—you’d never guess by looking—the actual temperature might be less stable than before. If you ignore BT031 long enough, you can end up with rock-solid frozen food in some spots, too-soft items in others, higher energy bills, and long-term stress on the system.

This guide breaks down what BT031 really means, how it shows up in everyday life, what you can safely do yourself, and how to reduce the chances of seeing this error again.

Inside the freezer compartment, there’s more going on than just cold air. The control board constantly reads information from different sensors to decide:

• How cold the freezer is right now
• When to start or stop the compressor
• How long to run the fans

The freezer air sensor is one of those key pieces. It measures the temperature of the air inside the freezer compartment. When Liebherr Refrigerator Error Code BT031 appears, it means:

The freezer air sensor is faulty or giving readings that don’t make sense, so the control board cannot rely on it.

What does the fridge do when it loses that reference? In many cases, it goes into a kind of “safe mode” and keeps the compressor running too much. The idea is: “better too cold than not cold enough,” but that’s not great in the long run.

You might not see the sensor itself—it’s usually hidden behind interior panels—but you definitely notice its problems through how the freezer behaves.

How BT031 Looks in Real Life: Common Symptoms

Most people don’t wake up thinking about freezer sensors. They notice symptoms first and then discover BT031 on the display. Those symptoms are usually pretty consistent.

You might see things like:

• A freezer that feels much colder than usual, with ice cream rock-hard and frosty buildup around packages.
• A compressor that seems to run almost non-stop, making the refrigerator louder and warmer at the sides.
• A freezer that should be cold enough, but food at the front or near the door isn’t as solid as the items in the back.

Sometimes the code will briefly disappear after unplugging the unit or resetting power, only to come back after the refrigerator runs for a while. That’s a classic sign that the control board keeps “watching” the sensor, doesn’t like what it sees, and triggers BT031 again.

Why Liebherr Error Code BT031 Happens: Main Causes

The official description for BT031 is a “freezer compartment air sensor error; freezer air sensor faulty, compressor may run continuously.” Behind that description are a few real-world reasons that pop up again and again.

In most cases, the problem is one of these:

• Defective freezer air sensor.
  The sensor itself ages out, absorbs moisture, or simply fails internally, so it sends bad data to the control board.
• Damaged or loose wiring.
  The small wires that connect the sensor to the electronics can get pinched, broken, or partially unplugged during transport, installation, or a previous repair.
• Corroded connectors or moisture.
  Freezers deal with cold surfaces and condensation. If moisture gets into a connector and starts corrosion, the electrical signal can become weak or unstable.
• Control board reading issues (less common).
  Sometimes the board itself misreads the sensor, even if the sensor is fine. This is rarer but still possible.

The key point: BT031 is not about ice buildup alone. It specifically points to a measurement problem in the freezer’s air sensor circuit.

First Steps at Home: Simple DIY Actions (No Tools, No Panels)

You don’t have to be a technician to do a few safe checks that can help tell whether BT031 is a random glitch or a real, ongoing problem.

1. Power Reset the Refrigerator

Start with the easiest move: Unplug the refrigerator from the outlet or turn off the circuit breaker. Wait at least 5–10 minutes so the control board fully powers down. Plug it back in and let the unit start as usual.

Then give it some time. Let the freezer run for 30–60 minutes and watch for: Does BT031 come back on the display? Is the compressor still running almost constantly?

If the code never returns and the freezer temperature feels normal, it might have been a one-time reading issue. If BT031 shows up again, the sensor or its wiring is likely really faulty.

2. Check Your Freezer Settings and Loading

Next, look at how the freezer is set and how it’s loaded. You don’t fix a broken sensor with settings, but you can avoid making the situation worse.

A few quick checks:

1. Make sure the freezer temperature setting is in the normal range (not set to extreme cold for no reason).
2. Don’t pack every inch of space; leave some gaps between items so air can circulate.
3. Avoid pushing items tightly up against the back wall or air vents.

If air can move freely and the set temperature is reasonable, the system doesn’t have to work as hard. That helps you see the sensor issue more clearly without extra “noise” from poor airflow.

3. Watch Actual Freezer Temperature, Not Just the Display

Because BT031 is a sensor error, you can’t fully trust the temperature that the control board thinks it has. If you want a quick reality check, use a simple standalone freezer thermometer (the cheap ones you hang on a rack are fine).

Place it in the center of the freezer and give it time to settle. Then compare:

1. Does the actual temperature match what you expect from your settings?
2. Is everything freezing solid, or are some items softer than they should be?

If the internal reading is way off from your experience or that simple thermometer, it’s another sign the sensor system is not telling the truth to the control board.

What You Shouldn’t Do

When BT031 pops up and the compressor is running a lot, it’s tempting to “force” the freezer to calm down by changing settings in extreme ways or trying to cheat the system. That usually backfires.

Constantly turning the temperature way up, then way down, trying to “trick” the freezer. Poking or prying at panels inside the freezer to “find the sensor” without knowing what’s behind them. Covering vents or sensors with tape, plastic, or food items to “shield” them.

These moves can make cooling worse, cause damage to interior parts, or create water leaks when ice eventually melts.

If BT031 keeps coming back after a reset, that’s your sign: the problem is inside the sensor circuit, not in your settings.

How to Reduce the Risk of Future Sensor Problems

You can’t completely prevent all electronics from failing, but you can create better conditions for the freezer and its sensors to survive longer.

A few simple habits help:

Keep the Door Seals in Good Shape

Every time you close the freezer door, the gasket (rubber seal) has to block warm, moist room air. If that seal is weak, you get extra moisture and frost inside, which is tough on sensors and everything else.

Good practice:

• Wipe the seals now and then so there’s no sticky residue.
• Make sure nothing (like a bag or box) is caught in the door.
• Watch for cracks, hard spots, or gaps in the gasket and replace it if it no longer seals well.

Avoid Extreme “Always-On” Cold

Boost modes and very low temperature settings are great short-term tools but bad long-term habits. Running the freezer at maximum cold all the time means more compressor runtime, more ice, and more stress.

Use those modes when you:

• Load a lot of unfrozen groceries
• Need a quick pull-down after restocking

Then return to normal settings once everything is frozen solid.

Give the System Room to Breathe

If your model and manual allow it, keep the condenser area reasonably clean (dust and pet hair removed). That helps the refrigerator get rid of heat efficiently, which means the compressor doesn’t have to fight as hard. A system that runs under less strain is kinder to all electronic components, including the freezer air sensor.

Final Takeaway: Living with (and Fixing) Liebherr Error Code BT031

Liebherr Refrigerator Error Code BT031 is the freezer compartment’s way of telling you the freezer air sensor is faulty or unreliable, and that’s why the compressor may run continuously. The appliance is trying to protect your food by staying cold at all costs, but that behavior is not sustainable.

A simple power reset, a check of settings and loading, and a quick look at real freezer temperature can tell you whether BT031 was a one-time glitch or a true hardware problem. If the error keeps coming back, you’re looking at a sensor or wiring issue that needs professional diagnosis and repair.

Until that’s sorted out, keep an eye on actual food temperature, not just the display, and don’t ignore signs like constant compressor noise or extreme frost. Once the faulty freezer air sensor is replaced and the system can “see” the real temperature again, your Liebherr can go back to running quietly, cycling normally, and keeping your food safely frozen—without flashing BT031 on the screen.