Hi all, first post, thanks in advance!! We have an LG LBUG3061YL split system air con system, that is not working properly (error CH02). Unfortunately its over 10 years old so getting someone to fix it is proving difficult. My searching has shown CH02 is the indoor unit sensors error, we have replaced them both but it didn't fix it. I then sourced and replaced the indoor PCB again it didn't fix it. The unit turns on, then runs for a couple of minutes, then when it turns the outside untit on, it runs for a further couple of minutes, then comes up with the error. I would like to try to trouble shoot more but I don't really fully understand how the system works. There are two electrical cables that go alongside the gas lines from the outdoor unit to the indoor unit in the ceiling cavity. One I believe simply supplies AC power to the indoor unit from the outdoor unit? The other I assume is some sort of communication from the indoor unit & control panel, to tell the out door unit to turn on/off? is that correct? Is that cable simply a voltage (AC or DC) or it some sort of communication like RS232? Is it feasible to in some way override the communication essentially putting a manual switch on the outside unit to just get it to work. I appreciate it wont be thermostatically controlled but at this stage our summer is currently over 100 degrees F in the day, and 80 at night!! Again any help really appreciated.

Purchasing a new house. A/C is 14 years old. I had an inspection on the two HVAC units and he wrote: "During heat mode the splits were 26.4 degrees and both units went into defrost cycle. Low run cap but within specs. recommend replacing cap and leaking oil fan motor". What exactly is the "splits" he is talking about? I have done a lot of automotive A/C and have rebuilt engines etc so not afraid of work, but zero house A/C experience. Can I easily replace the capacitor (is it even needed?) and the fan?