LG Dishwasher Not Drying Dishes: How to Fix the Heating and Drying System

LG dishwashers use a combination of heated rinse, a vent fan, and condensation drying to dry dishes. Unlike brands that use a dedicated drying heater element, many LG models rely on residual heat from the final hot rinse combined with a vent fan that circulates air through the tub. If your dishes come out wet, the problem could be the rinse aid system, the vent fan motor, the heating element (which heats the rinse water), or simply user technique. This guide covers each drying component, how to test it, and how to fix or replace failed parts.

LG's approach to drying is fundamentally different from brands that blast hot air with an exposed heating element. The Hybrid Dry system on newer LDT models opens a vent door and runs a small fan to pull moisture out of the tub after the hot rinse. The hot stainless steel tub walls promote condensation drying — moisture evaporates from hot dishes and condenses on the cooler side walls, dripping down to the drain. This system is energy-efficient but depends on every component working correctly.

Before You Start

• Tools needed: Phillips #2 screwdriver, Torx T15, multimeter, flashlight
• Parts needed: Depends on diagnosis — vent fan ($25-50), rinse aid dispenser ($30-60), or heating element (~$40-90)
• Time required: 20-45 minutes depending on component
• Difficulty: Intermediate
• Safety warning: Disconnect power at the circuit breaker before testing any electrical components. The vent fan and heating element receive line voltage during operation.

Diagnosing the Drying Problem

Work through these checks in order of frequency:

Check 1: Rinse Aid Level and Setting

Open the rinse aid cap on the inner door panel and verify the reservoir is full. Rinse aid is critical for LG's drying system — it reduces water surface tension so droplets sheet off dishes rather than forming beads. If the rinse aid indicator on the display panel is lit, refill the reservoir. Also check the dosage dial inside the cap — setting 3-4 is correct for most water hardness. Setting 1 may not deposit enough rinse aid for effective drying.

Check 2: Loading Technique

LG's condensation drying works best when: (1) plastic items are on the top rack (plastic does not retain heat like ceramic/glass), (2) items are angled to allow water runoff, (3) concave items like bowls and cups are tilted, not face-up. If only plastics come out wet but ceramics are dry, this is normal behavior for condensation drying — not a malfunction.

Check 3: Vent Fan Operation

During the drying phase, listen at the top-right area of the dishwasher door. You should hear a soft whirring sound from the vent fan. If silence during what should be the drying phase — the fan motor may have failed. The vent fan on most LG models sits behind the inner door panel near the top-right corner.

Check 4: Heating Element Function

The final rinse must reach at least 150F for effective condensation drying to occur. If the heating element has failed, rinse water stays lukewarm and dishes cannot dry properly. Test: start a cycle, wait until the final rinse phase, cancel, and immediately open the door. The water in the tub should be very hot. If lukewarm — the heater has failed (see the dedicated heater replacement guide).

Step-by-Step Instructions

Step 1: Test and Replace the Vent Fan Motor

Disconnect power. Open the dishwasher door. The vent assembly is located behind the inner door panel at the top-right corner (on most LG models — some have it at the top-left). Remove the inner door panel screws (Torx T15) to access the vent assembly. The vent includes a small DC fan motor connected by a 2-pin connector. Disconnect the connector and test the motor: apply 12V DC from a battery or power supply to the motor terminals. It should spin freely. If it does not spin, or spins weakly, replace the fan motor.

Step 2: Inspect and Clean the Vent Duct

With the vent assembly accessible, check the vent duct for debris or blockage. Mold and lint can accumulate in the vent passage, restricting airflow even when the fan works. Clean the duct with a bottle brush and warm soapy water. Also check the vent door flap — it should open freely when pushed and spring closed when released. A stuck flap prevents air circulation.

Step 3: Check the Vent Door Actuator (If Equipped)

Some LG models use a wax motor actuator to open the vent door at the start of the drying phase (similar to the detergent dispenser actuator). If this actuator fails, the vent door stays closed and moisture cannot escape. Test by starting a cycle and waiting for the drying phase — listen for a click from the vent area indicating the door opening. No click suggests actuator failure.

Step 4: Verify Rinse Aid Dispensing

Fill the rinse aid reservoir. Run a cycle with a few cups or glasses on the top rack. After the cycle completes, check the dish surfaces. Proper rinse aid dispensing leaves dishes with a uniform sheen and no water spots. If water beads remain, the dispenser mechanism may not be releasing rinse aid properly. The dispenser cap has a gasket that can deteriorate, or the internal mechanism may be clogged with old rinse aid residue.

Step 5: Test the Heating Element (If Drying AND Washing Temp Are Affected)

If both wash temperature and drying performance are poor, the concealed heating element has likely failed. Access the element terminals from the bottom of the unit (remove lower access panel and LoDecibel insulation pad). Disconnect the terminal wires and measure resistance with a multimeter: 10-30 ohms = good element, OL = failed. See the dedicated heating element replacement guide for full installation procedure.

Step 6: Clean the Stainless Steel Tub Walls

Condensation drying depends on moisture condensing on the tub walls. If walls are coated with grease film or mineral scale, condensation efficiency drops. Run a vinegar cleaning cycle: place 2 cups of white vinegar in a cup on the top rack, run the hottest cycle empty. This removes the film and restores the metal surface's condensation properties.

Step 7: Adjust Cycle Settings for Better Drying

On LG dishwashers, the Extra Dry or Turbo Dry option extends the drying phase and runs the vent fan longer. Enable this option if you are not using it already. Also select the highest temperature setting available for the wash cycle — hotter final rinse means more residual heat for drying. On ThinQ-enabled models, you can customize drying intensity through the app.

Step 8: Post-Fix Verification

Run a full Normal cycle with Extra Dry enabled, a full rinse aid reservoir (setting 4), and a representative load (mix of ceramic plates, glasses, and a few plastic items). After the cycle completes, wait 5 minutes before opening the door (this allows the final condensation phase). Ceramic and glass items should be completely dry. Plastic items may have minor moisture — this is normal for condensation drying systems and is not a defect.

When to Call a Professional

• The heating element reads correct resistance but water never heats — control board not sending voltage
• Vent fan motor tests good but never activates during drying — control board relay failure
• Multiple drying components have failed simultaneously — usually indicates a broader electrical issue
• Water pools inside the vent duct itself — the vent seal or routing may be incorrectly installed

Cost Comparison: DIY vs Professional

Need Professional Help?

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• Dishwasher repair cost guide

FAQ

Q: Why does my LG dishwasher leave plastic items wet? A: This is normal for condensation drying systems. Plastic does not retain heat the way ceramic and glass do, so it cannot drive evaporation effectively. Place plastic items on the top rack and use the Extra Dry option. No dishwasher using condensation drying can fully dry plastics.

Q: Should I open the LG dishwasher door after the cycle to help drying? A: Some newer LG models auto-open the door slightly at cycle end (Door Open Dry feature). If your model does not have this, cracking the door 2 inches after the cycle completes helps release trapped moisture. Wait at least 5 minutes after the cycle ends before opening fully.

Q: How does LG TrueSteam affect drying? A: TrueSteam is used during the WASH phase (to soften baked-on food), not during drying. It does not negatively impact drying. However, TrueSteam adds moisture during the wash, which is why the drying phase must work correctly to remove that extra moisture.

Q: My LG dishwasher used to dry well but now does not — what changed? A: Most likely the rinse aid ran out (check the indicator), the vent fan motor weakened or failed, or mineral scale has coated the tub walls reducing condensation efficiency. Try refilling rinse aid and running a vinegar cleaning cycle first.

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