LG multi-split: one outdoor unit cannot heat and cool at once

What Does Error Mode conflict Mean?

LG states that on a multi-product system every indoor unit connected to one outdoor unit has to run in cooling only or in heating only. Cooling and dehumidification cannot run at the same time as heating, while air purification and fan modes are unrestricted, so one room set the wrong way stops another from getting what it asked for. Applies to: LG multi-split systems where several indoor units share a single outdoor unit, as described in LG help-library guidance This applies to LG multi-split arrangements where several indoor units share one outdoor unit. Heat recovery systems, which are a different architecture, can serve simultaneous heating and cooling, and single-split installations have no conflict to resolve. Confirm how many indoor units your outdoor unit serves. Owner-safe checks: Walk through every room with an indoor unit and note which mode each one is set to, including any that are switched on but unused. | Switch off indoor units in rooms nobody is using rather than leaving them running in a conflicting mode. | Set every remaining unit explicitly to the same mode rather than relying on automatic selection. Qualified technician: A conflict that persists after every indoor unit is set to the same mode is no longer a mode conflict and needs the system examined. | Changing how a multi-split is configured, including adding or reassigning indoor units, is installer work rather than a settings change.