LG CH06 fault

[Airsteve]

Hi all, I got called to a ducted LG split unit today thats out on a CH06 fault. I dont deal much with LG.
I reset the controller and powered down the unit but it will not clear the code or attempt start all. Disconnected indoor pipe thermistor, measured 7.5k ohms at aprox 18 deg C. Voltage across sensor plug when connected is 2.7vdc. I have 5vdc from the board. Can anyone advise me of what the voltage out of the board with sensor disconnected should be. When i contacted LG tech support they could not tell me what that voltage should be only that my 2.7vdc with sensor connected is incorrect.
Unit details; Indoor B30AHYN661 Outdoor B30AHYUE61
Thanks.

[install monkey]

Indoor outlet pipe sensor
• Open / Short
• Soldered poorly
• Internal circuit error
Normal resistor : 5KΩ/ at 25°C (Unplugged)
Normal voltage : 2.5Vdc / at 25°C (plugged)

[Airsteve]

Thanks install monkey, looks like the sesnor is around the mark. I am just trying to make sure the voltage out of the board is correct or incorrect before deciding to change. If it is higher than supposed to be then voltage across the sensor will be incorrect.

[Tayters]

Generally feed to pins on PCB would be 5V DC when probe unplugged.

[install monkey]

stick a fixed resistor on it as a temporary to see if sensor is going out of range intermittantly or if it is failing when voltage is applied

[Tayters]

http://www.lgcomfortcooling.co.uk/technicalArchive.asp?subID=6&type=faultcodes


Mine of info here. If a residential unit then 06 an inverter current error although could be brought up from dodgy condenser probe if I recall. Think definition of residential is a wall mount, otherwise commercial.

Cheers,
Andy.

[Airsteve]

Thanks for the info everyone.