When your LG air-con flashes the CH 21 code, it is warning you about a compressor overcurrent problem. That means the main cooling part of the unit is trying to pull more power than normal. Let’s try to understand what this CH 21 code means in LG aircon and how to fix it.
What Does LG Aircon CH 21 Mean?
Simply put, CH 21 tells you that the compressor is pulling far too much electric current. Since the compressor is its engine, the aircon shuts itself down to avoid further damage whenever that happens. So both cooling and heating modes stop working until the problem clears up.
Why CH 21 Error Happens
Several reasons can cause compressor overcurrent in Singapore homes:
Dirty Condenser Coil
Dust and dirt make it hard for the aircon to release heat, forcing the compressor to work harder.
Low Refrigerant Gas
Insufficient refrigerant causes poor cooling and puts extra load on the compressor.
Faulty Compressor
Age or damage can make the compressor malfunction.
Blocked Airflow
Clogged filters or blocked vents reduce airflow, increasing compressor pressure.
Electrical Issues
Voltage instability or wiring problems common in older HDB flats may trigger this.
How to Fix LG CH 21 Error
Reset the Aircon
Shut off the unit and pull the plug. Give it about five minutes, then plug it back in and turn it on. If CH 21 still pops up, move on to the next step.
Check and Clean Filters
Clogged filters block airflow. Take the air filters out, rinse them under clean water, and let them air-dry completely before sliding them back in.
Check the Outdoor Unit
Make sure the outdoor condenser isn’t blocked by leaves, walls, or furniture. Any jammed-up area can trap heat and cause trouble.
Call a Professional Technician
When the easy steps don’t fix the issue, call a licensed air-con service team. They have the tools and know-how to diagnose the error and get the unit running again.
A licensed aircon technician will:
- Measure compressor current
- Check refrigerant levels
- Clean condenser coils
- Repair or replace faulty components
Can I Ignore CH 21 Error?
No. Continuing to use your LG aircon with this error can damage the compressor permanently. Compressor replacement costs are high. Prompt repair is always cheaper.
How Singapore Climate Affects CH 21
Singapore’s hot and humid weather puts extra stress on air conditioners. Regular use during warm months increases the chances of errors like CH 21. Regular maintenance helps prevent these problems.
FAQ About LG CH 21 Aircon Error
What’s the very first thing I should check for a CH 21 error?
Clean the air filters and look for anything blocking the vents on the outside unit. If everything seems clear, call a technician.
Can I fix a CH 21 error myself?
You can reset the unit and clean the filters, sure. But any problems with the compressor or wiring still need a pro.
Does a CH 21 code mean my air-con is broken?
Not necessarily. Often it’s just a small airflow or power glitch. Ignore it, though, and you could end up with bigger damage.
How often should I service my LG air-con in Singapore?
A check every three to six months is best, especially if you run the unit every day.
Is the CH 21 error common in LG units sold in Singapore?
Yes, you’ll see it pop up on both old and new inverter models in HDBs and condos.
Final Words
If your LG aircon shows CH 21 error in Singapore, it signals a compressor overcurrent issue. While some simple checks like cleaning filters or restarting the system can help, often professional servicing is needed. Regular aircon maintenance helps avoid such costly problems.
