LG Dryers: Sensor Technology and What It Means for Repair
LG dryers pack more technology into the drying process than most people realize. The moisture-sensing system uses metal strips inside the drum that measure electrical conductivity through the tumbling clothes — wet fabric conducts electricity, dry fabric doesn't. LG's algorithm continuously samples this data and adjusts the drying time in real-time rather than relying on a fixed timer.
The Flow Sense system is LG's vent monitoring feature. It measures exhaust airflow and alerts you when the vent is becoming restricted. This is genuinely useful technology that can prevent fires, but it can also generate false blockage warnings when the sensor or pressure switch malfunctions. Some LG models also use a direct-drive motor with no belt — the motor connects directly to the drum through a coupling. This eliminates belt wear but changes the failure modes entirely.
An LG Dryer Showing Flow Sense d80 Warning
A homeowner in Plymouth called about their LG electric dryer that was displaying a d80 Flow Sense warning. The manual said this meant 80% vent blockage. They had already hired a vent cleaning company that cleaned the entire vent run from the dryer to the exterior — four inches of lint from a 20-foot run. But the d80 warning persisted after cleaning.
This is a situation I see regularly with LG dryers. The Flow Sense system uses a pressure switch that measures the difference between drum pressure and exhaust pressure. If the switch itself is faulty, or if the small rubber hose connecting the switch to the exhaust duct has cracked or come loose, the system reads a pressure differential that doesn't actually exist.
I found the rubber sensing hose had developed a hairline crack about three inches from the pressure switch. Air was leaking in through the crack, throwing off the pressure reading. I replaced the hose — about eight inches of tubing — and the d80 warning cleared immediately. The vent was perfectly clean thanks to the cleaning company. The dryer itself just needed a $5 piece of tubing to accurately read what was happening. I ran two full test loads to confirm the warning stayed off and drying times were normal.
Common LG Dryer Problems
Flow Sense False Blockage Warnings
The Flow Sense system can display d80 or d90 blockage warnings even when the vent is clean. The pressure switch or its sensing hose can fail, giving false readings. I verify actual vent airflow before condemning the sensor, because sometimes the vent really is blocked even if it was recently cleaned.
Moisture Sensor Bar Contamination
The metal moisture sensor strips inside the drum get coated with residue from dryer sheets and fabric softener. When coated, they can't accurately measure moisture levels, causing the dryer to shut off too early with damp clothes. Cleaning with rubbing alcohol and fine sandpaper often fixes this without any parts needed.
Drum Roller Bearing Wear
LG dryers that use drum rollers will develop squealing or thumping sounds as the rollers wear out. The noise typically gets worse over time and is most noticeable when the dryer is running with a small load. I replace rollers as a set — both rear rollers plus the idler pulley.
Main Control Board Failure
The electronic control board manages the moisture sensing, temperature regulation, and motor control. When it fails, you can get anything from a completely dead dryer to erratic cycle behavior to error codes on the display. I verify all downstream components before replacing the board, because a failed thermistor or sensor can mimic board failure.
LG Dryer Parts I Source
Heating elements, gas igniters and coils, drum roller kits, idler pulleys, moisture sensor bars, thermistors, thermal fuses, main control boards, and Flow Sense pressure switches. LG dryer parts are brand-specific, but I have reliable sourcing channels that keep most repairs to a single visit.
LG Dryer Repair: Technology That's Worth Maintaining
LG dryers are well-built appliances with genuinely useful technology. The moisture sensing and Flow Sense features save energy and protect your home when they're working correctly. When they're not, you need someone who understands how these systems actually work — not just how to swap parts. That's what 45 years of experience gives you.