I need a control board for a discontinued indoor LG unit LM360HE. It's difficult to find this part. Are there new or current LG indoor units that could work with this system (system model: 920Rg)?

It sounds like you were experiencing an issue with one of the indoor units on your LG dual inverter air conditioner, where it was stuck in defrost mode while the other unit was working properly in heating mode.
It sounds like you've already replaced the control board of the indoor unit that was stuck in defrost mode and it fixed the problem. The control board is responsible for controlling the various functions of the air conditioner and it is a common cause of malfunction in air conditioning systems.
It's great that you've been able to fix the issue, but if the problem comes back or you're experiencing other issues, it's best to contact LG's customer service or a professional technician for further assistance.
It's important to note that troubleshooting and repairing air conditioners can be dangerous, especially if you're not familiar with the device, so it's best to contact a professional technician if you're not comfortable working with it.

check capacitors to compressor

Here is an answer from official LG site:
The CH05 error message means you have an indoor / outdoor unit communication error. It can be caused by any of the following issues:

• No power on indoor unit
• Indoor/outdoor unit power connection error / communication line not installed
• Communication error caused by external noise
• Indoor/outdoor unit communication circuit parts burned.

In my opinion if it works for some time and then shows the error it may be communication error caused by external noise.
You should contact the trained technician to deal with that problem.

According to an LG installation manual for the LMU540HV, if the flashing light is viewed on the indoor unit with the ceiling cassette light on the far right flashing 5 times, it is an error code meaning there is a communication error between indoor and outdoor units. I would start by making all indoor and the outdoor units have power. I would especially check to see that fuses or circuit breakers to the outdoor unit have not failed. Or check the outside disconnect to make sure it is working. Check with a volt meter to be sure you have 220 volts present to the outdoor unit. Also, if the 4 indoor units have emergency power off switches, make sure all 4 are turned on. Checking to see power is present both indoors and outdoors a good place to start. It the outdoor unit has power, there may be a relay that has failed or a power circuit board has failed that would cause it not to communicate.

F2 is an indoor pipe sensor fault. You will need an air con tech or electrician to do this as the sensor is wired into the indoor board. Gree parts can be a bit difficult to obtain but a similar sized pipe sensor from an LG or Teco unit will work. You may have to "splice" the new sensor onto the existing pipe sensor wiring as the connection to the indoor board will likely be different. Contact LG or Teco for your colsest parts outlet or buy direct from them.

check that you have power to indoor unit 120volts if yes check fuse on control board of indoor unit check control board for 24 volt the indoor unit controls the outdoor unit

If this is a LG Airconditioning unit.
It has reached the set parmeter of the safety switch point.
1 The unit could be running on too low refrigerant charge and cuts out on low temperature on the indoor unit coil (-5°C longer that 30sec switch off)
2 The unit might be drawing to much current, to much refrigerant, cutting out on high pressure.

Check the refrigerant charge and check the indoor pipe temperature thermister (calibrated at 5kΩ @ 25°C)

I have run into this with the LG brand systems. try shutting power off to the outdoor unit to reset all units. If problem persists, it could have to do with a charge level of refrigerant (freon) or possibly a failed control board.

Btw, I’m available to help over the phone in case u need at https://www.6ya.com/expert/cody_17f08cf8e340c06c

1.sensar of remote control.
2.indoor unit sirkit board may be there is problem.change sirkit board by new one
3.if any requirement abt airconditioner pls mail me i can send u spare parts of air conditioner,.
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