Heat Pump Troubleshooting

LG Heat Pump Troubleshooting Help Library – http://www.lg.com/ca_en/support/product-help?categoryId=CT32001121&superCategoryId=CT20098038&searchChck=false&reSearch=&search=

Helpful LG Video Tutorials – http://www.lg.com/ca_en/support/video-tutorials?categoryId=CT32001121&superCategoryId=CT20098038&searchChck=false&reSearch=&search=

LG Warranty Informationhttp://www.lg.com/ca_en/support/warranty

Out of Warranty LG Product Informationhttps://lgoutofwarranty.ca/en/main/flatrate.do

LG Supporthttp://www.lg.com/ca_en/support

Fault Code List – http://www.orionair.co.uk/lg_air_con_fault_codes.htm

Some Steps Before Calling for a Service Request

Dirty Air Filter

Periodically, an LG air conditioner’s air filter may become dirty. If the air filter is clogged with trapped particles, the airflow from the unit may be blocked and the cooling capacity is reduced. Check the air conditioner’s filter twice a month to determine if cleaning is required. Pull the air filter out of the front grille assembly and examine it for buildup. If dirty, clean the filter with lukewarm water. Be sure to shake the air filter afterward to get rid of any excess water and replace it in the grille assembly. When an air filter becomes torn or damaged, it should be replaced with a new filter, which can be purchased from an authorized dealer or customer service center.

Check Your Power Supply

One of the most common problems with ductless heat pumps is problems occurring between the electricity supply on the inside of the house, and the pump on the outside. If you have a switch on the indoor part of your pump, check that it is still turned to the “On” position, and that the light (if there is one) is on. There is another switch on the heat pump, usually located on the inside of the pump near to the blower door. You will need to check that this is not turned off. Electrical circuit breakers can be found on the side of the pump, and should be checked to ensure that they have not been tripped.

Check Your Internal Unit

Your ductless heat pump will be connected to an internal panel, which sends the heat to the rooms of your house. Check that this has not been damaged by members of the family, or pets, and then remove the outer cover. The internal unit has a thermostat that controls the heat on the inside of the home, and this needs to be checked. Make sure that your thermostat has not run out of batteries, or has not become disconnected from the electricity supply. You may find that the LED display is not on, and this is an indicator that you have no power. The thermostat should have a button on the outside of the case, like a panic button, which will reset the device if you press it and hold. You should hear a beep, which will indicate that you can now reset the time. If there is no beep, your thermostat has either run out of power, or failed for some other reason. If in doubt, replace the thermostat.

Check your Outdoor Unit

Once your indoor unit is working, check the outside part. This will usually be directly adjoining your inside panel. If you cannot hear the pump running when you are close to it, this suggests that the pump has failed. If you are struggling to get it to work in cold weather, you may need to remove any frost or ice which has formed on the pump, and then press “Defrost” on the external control panel. This should allow the pump to start working again, once the system has warmed up.

Is the unit running?

If your unit is not operating, you should begin your ductless ac troubleshooting by checking the display on the fan coil for a fault code. In most units, the display will show an E with a number. With that number you can narrow down the problem by referring to the user manual/installation instructions.

Fault Code List – http://www.orionair.co.uk/lg_air_con_fault_codes.htm

Next, you should check the room temperature setting. On most units this is done with the remote control. Ensure that the unit is in the proper mode and the setpoint is correct. You should also make sure the unit has been off for at least three minutes.

If the display on the air handler is blank, check the fuse or breaker for the unit. In the case of a tripped breaker, you should check the wiring connections in the outside unit. Some units also have a fuse on the control board in the air handler.

Is it blowing air but not cooling?

Continue your ductless ac troubleshooting by checking the air filter. It should be washed at least every month. Also check to see if there is any ice buildup on the coil.

If there is ice build up, check to make sure the fan is working. Make sure the blower wheel is free to move. If it is free and the fan is not working then the problem is probably the motor or the control board. If the fan is working, allow the ice to melt and check the refrigerant level in the unit.

Ductless AC Troubleshooting, At the outdoor unit…

If there is no ice and the fan is working, you should go to the outdoor unit. If the fan on the outside unit is not running, you should check the dual run capacitor. Our Capacitor testing guide will help you with that. If the capacitor can is bulging, it is a good indication that it is bad.

https://www.youtube.com/watch?time_continue=16&v=bCZcNlMznTA (Capacitor testing video)

If the capacitor is good the condenser fan motor may be bad. You can use our fan replacement guide to help you.

If the fan is running, feel the compressor to see if it is running. If it is hot to the touch and not running, shut off the power and cool the compressor by pouring water over it. Then, check the outdoor coil and make sure it is clean. You should also check the dual run capacitor.

After the unit is running, you should check the refrigerant level

If, after the compressor is cooled down, the unit makes a loud humming noise when it is trying to start, the compressor rotor may be stuck. You can use a hard start capacitor to try to get it to run. If the compressor still does not start, it may need to be replaced. You can use our compressor testing guide to check to be sure.

If the fan and compressor are running but the cooling or heating is insufficient, start by cleaning the unit. Ensure the fan coil, filter, and condenser coil are clean. Then you can check the refrigerant level and adjust per the operating instructions.

If the unit’s refrigerant charge is adequate, the unit may be improperly sized. The only way to tell if the unit is the proper size is through a process called a load calculation

Is the unit leaking water?

If your unit is dripping water, you should begin your ductless ac troubleshooting by checking the drain hose to see if it is clogged. The easiest way to do this is with a bottle of water. Outside, stick the end of the hose in a bottle of water. Seal around the bottle opening with your hand. Then squeeze the water bottle and then pull the hose out. The water should drain but this may need to be done a few times to make sure the line is clean.

If the hose was not clogged, check to make sure the fan coil unit is sloped properly. The unit should be slightly out of level with the end attached to the drain hose slightly lower than the other end.

Lost or broken remote control?

If the remote does not work, you can replace the batteries. If it still does not work or you can’t find it, most units have an emergency button on the fan coil unit that you can push to make it run. It will then operate as necessary to maintain a default temperature.

You should complete your ductless ac troubleshooting by observing a complete heating or cooling cycle.


Information on Heat Pump Remote Controller (Button Instructions, Controls, Guide)

Information on Heat Pump (Button Instructions, Controls, Guide)