What does Er rt mean on a LG refrigerator?

Er rt means: Room. The most likely parts involved are ambient room temperature sensor, main control board.

How much does it cost to fix Er rt?

A typical main control board replacement costs about $200–$800 nationally, parts and labor included. This is a reference range, not a quote — local prices vary.

Is it safe to keep using my LG fridge with the Er rt code?

Usually yes for a short time, since this code is about a sensor reading, not a safety hazard. Watch your food temperatures closely and get it repaired soon, because cooling may not be as steady.

Will the Er rt code go away by itself?

Sometimes a power reset clears a one-time glitch. If the sensor or board has truly failed, the code will keep coming back until the part is replaced.

Error codes › Refrigerator › LG

LG Refrigerator Er rt Error Code

Room

Applies to: All digital display models. May also appear as E rt, rt.

What's going on

On an LG refrigerator, Er rt means the control board is getting a bad reading from the room temperature sensor. The fridge may keep cooling, but it can't adjust for the temperature of the room around it. A power reset is worth trying once, but if the code comes back, plan on calling a qualified appliance technician.

LG refrigerators with a digital display use a small sensor, called a thermistor, to measure the air temperature in the room. This sensor sits on or near the main control board. The board uses that reading to fine-tune how the fridge runs, such as how hard the compressor and fans work.

When the sensor's signal is missing or makes no sense, the board decides the sensor is open (a broken connection) or shorted. It then shows Er rt. The fridge usually keeps running on default settings. Cooling may be less even or less efficient until the problem is fixed.

This code applies to LG models with a digital display. Codes can differ between model generations, so check your model number in your owner's manual or on LG's support site to confirm.

Likely causes

ambient room temperature sensor — The sensor itself can fail, or its wire connection can loosen or break. Either way, the board gets no usable reading and shows the code.
main control board — Because the sensor is mounted on or near the board, a fault on the board can cause the same error. In many cases the fix is replacing the main control board.

The same code can mean different things on different model generations. Check the model number on your refrigerator's rating plate before ordering parts.

Can you fix it yourself?

Not a DIY repair. This one needs a technician with the right tools and parts.

Safe things to check first

Unplug the refrigerator or switch off its breaker for a few minutes, then restore power and see if the code clears.
Make sure the fridge isn't sitting in direct sun or right next to a heat source like an oven or heater vent, which can confuse readings.
Check that food is still cold. Use an appliance thermometer if you have one, and move perishables to a cooler if the temperature is rising.
If the code returns, write it down along with your model and serial numbers to give to the technician.

When to call a technician

If Er rt comes back after a power reset, call a qualified appliance technician. This repair involves the sensor and control board inside the unit and is not a do-it-yourself job.

What the repair usually costs

$200–$800

Main control board replacement, parts and labor — national reference range

Confidence: high (3+ independent cost guides agree). Plus a service call fee of about $50–$100, often credited toward the repair.

This is not a quote. Prices vary by region and by model.

Repair or replace?

It depends on age. This repair can cross $720, about half the price of a typical new refrigerator. If yours is near the end of a typical 10–15 year lifespan, compare replacement prices before booking a repair.

A typical new refrigerator costs about $600–$2,300.

Check your refrigerator — free, 2 minutes

Common questions

What does Er rt mean on a LG refrigerator?: Er rt means: Room. The most likely parts involved are ambient room temperature sensor, main control board.
How much does it cost to fix Er rt?: A typical main control board replacement costs about $200–$800 nationally, parts and labor included. This is a reference range, not a quote — local prices vary.
Should I repair or replace my refrigerator?: It depends on age. This repair can cross $720, about half the price of a typical new refrigerator. If yours is near the end of a typical 10–15 year lifespan, compare replacement prices before booking a repair.
Can I fix Er rt myself?: Not a DIY repair. This one needs a technician with the right tools and parts.
Is it safe to keep using my LG fridge with the Er rt code?: Usually yes for a short time, since this code is about a sensor reading, not a safety hazard. Watch your food temperatures closely and get it repaired soon, because cooling may not be as steady.
Will the Er rt code go away by itself?: Sometimes a power reset clears a one-time glitch. If the sensor or board has truly failed, the code will keep coming back until the part is replaced.