Troubleshooting - aerona-chofu-ashp/docs GitHub Wiki
What does 'LC' on the display mean?
'LC' indicates the weekly Legionella Cycle ran to disinfect the hot water cylinder, but was unsuccessful at reaching the desired temperature within the time limits of the cycle. Likely somebody drained some hot water during that time. It is not usually a problem to miss the occasional weekly cycle, as a fortnightly disinfection is sufficient for most people unless they have weak immune systems.
To clear the error, hold down the '+' and '-' buttons on the room controller for a few seconds until the message clears.
If you get an 'LC' error every week, check that your hot water immersion heater is being corrected activated by terminal 46 on the outdoor unit, and that setting 5146 ('Terminal 46 : DHW Electric Heater or Backup Heater') is set to 0 ('DHW Electric Heater'). You may also wish to change the Legionella cycle to run at a different time.