When an LG air conditioner runs but doesn’t cool, the cause is usually a setting, a dirty filter, or restricted airflow long before it is anything serious. LG split ACs use a Dual Inverter compressor that modulates speed, so the cooling behaviour differs from old fixed-speed units. Here is a complete India-focused guide to diagnosing and fixing an LG AC that is not cooling.
Quick Checks Before Anything Else
- Mode and temperature: Confirm the remote is on Cool mode (snowflake), not Fan or Dry, and the set temperature is below room temperature (try 24 °C). It is easy to leave it in Fan mode.
- Power and voltage: Indian voltage swings hit ACs hard. Ensure the supply is stable; a stabiliser is recommended unless your model is explicitly stabiliser-free.
- Jet / Fast cooling: Use Jet mode for a quick pull-down, but it should drop back to your set temperature afterwards.
- Outdoor unit running: Check the outdoor compressor and fan are actually working. If only the indoor blower runs, cooling won’t happen.
Common Causes and DIY Fixes
1. Dirty Air Filters
This is the single most common reason for weak LG cooling in India. Clogged filters choke airflow, ice up the coil, and slash efficiency.
- Open the indoor unit’s front panel and slide out the mesh filters.
- Wash under running water, dry fully in shade, and refit.
- Clean them every 2–3 weeks in heavy-use summer months.
For a full walk-through, see how to service an AC at home.
2. Blocked or Dirty Outdoor Condenser
The outdoor unit dumps heat outside. If its coil is caked with dust, leaves, or is boxed in with no airflow, the AC can’t reject heat and cooling collapses. Switch off power and gently hose down the condenser fins; ensure at least 30 cm clearance around the unit.
3. Low Refrigerant / Gas Leak
If the AC cools weakly, the indoor coil ices up, or you see oily residue at the pipe joints, refrigerant may be low due to a leak. Topping up gas without fixing the leak is a temporary patch — call a technician to find and seal the leak, then recharge.
4. Iced-Up Indoor Coil
Ice on the indoor evaporator (from a dirty filter or low gas) blocks airflow entirely. Switch the AC off, run it in Fan mode to melt the ice, then address the root cause (clean filter or check gas).
5. Dual Inverter Compressor or PCB Fault
If the outdoor unit never starts, or the AC throws an error code, the issue may be the compressor, capacitor, or control PCB. LG Dual Inverter compressors carry a long warranty (often 10 years) in India, so a failure is usually a service call, not a DIY repair.
LG AC Symptom Quick-Reference
| Symptom | Likely Cause | First Fix |
|---|---|---|
| Blower runs, air not cold | Wrong mode / low gas | Set Cool 24 °C; check gas |
| Weak airflow | Dirty filter | Wash filters |
| Ice on indoor coil | Dirty filter / low gas | Fan mode to defrost, then fix cause |
| Outdoor unit not starting | Capacitor / compressor / PCB | Call LG service |
| Error code on display | Sensor / system fault | Decode code first |
Helpful Tools and Parts
For filters, remote replacements, and AC servicing kits you can use at home:
Browse AC Cleaning Kits on Amazon India ↗
When to Call LG Service
Call an authorised LG technician if: the outdoor unit won’t start, the coil keeps icing despite a clean filter (gas issue), an error code persists, or you suspect a Dual Inverter compressor fault under warranty. Book via the LG ThinQ app or the toll-free helpline.
Related Guides
Compare with the general AC not cooling fix guide, and for other brands see the Voltas AC not cooling fix and Daikin AC not cooling fix.
Frequently Asked Questions
Why is my LG AC running but not cooling?
Most often the remote is in Fan or Dry mode, the filter is clogged, or refrigerant is low. Set it to Cool at 24 °C, wash the filters, and confirm the outdoor unit is running. If the coil ices up, suspect low gas.
What is Jet mode on an LG AC?
Jet (Fast/Himalaya Cool) mode runs the AC at full power to cool the room quickly, then returns to your set temperature. It is normal for it to ramp down — that is the Dual Inverter working efficiently.
How often should I clean my LG AC filter in India?
During peak summer, clean the mesh filters every 2 to 3 weeks. In dusty areas or with continuous use, clean them weekly to keep cooling strong and electricity bills low.
Is regassing my LG AC a DIY job?
No. Refrigerant handling needs a licensed technician with proper gauges and leak detection. Always have the leak repaired before recharging, or the gas will simply escape again.