Daikin air conditioner error U4
Meaning
Signal transmission error (between indoor unit and outdoor unit)
General meaning for the brand's models, unless a model's own manual says otherwise.
Meaning
Communication failure, between indoor & outdoor
General meaning for the brand's models, unless a model's own manual says otherwise.
Meaning
Malfunction of transmission between indoor and outdoor unit
General meaning for the brand's models, unless a model's own manual says otherwise.
Meaning
Communication abnormality
Models
FTKB09AXVJU, FTKB12AXVJU, FTKB18AXVJU, FTKB24AXVJU, FTKN09AXVJU, FTKN12AXVJU, FTKN18AXVJU, FTKN24AXVJU, FTXB09AXVJU, FTXB12AXVJU, FTXB18AXVJU, FTXB24AXVJU, FTXN09AXVJU, FTXN12AXVJU, FTXN18AXVJU, FTXN24AXVJU, RKB09AXVJU, RKB12AXVJU, RKB18AXVJU, RKB24AXVJU, RKN09AXVJU, RKN12AXVJU, RKN18AXVJU, RKN24AXVJU, RXB09AXVJU, RXB12AXVJU, RXB18AXVJU, RXB24AXVJU, RXN09AXVJU, RXN12AXVJU and 2 more
Meaning
Failure of transmission (between indoor unit and outdoor unit)
Models
ATKB25ZVMV, ATKB35ZVMV, ATKF25ZVMV, ATKF35ZVMV, FTKB25ZVMV, FTKB35ZVMV, FTKB50ZVMV, FTKB60ZVMV, FTKF25ZVMV, FTKF35ZVMV, FTKF50ZVMV, FTKF60ZVMV, FTKF71ZVMV, FTKM25AVMV, FTKM35AVMV, FTKM50AVMV, FTKM60AVMV, FTKM71AVMV
Meaning
Communication error
Models
FTXN-LV1B9, RXN-LV1B9
Causes and how to check
- 5 possible causes
- the repair procedure printed in the service manual
- the cited manual page, and follow-up questions
No account needed to look up codes.
Model series: ATKB, ATKF, FTKB, FTKF, FTKM, FTKN, FTXB, FTXN, RKB, RKN, RXB, RXN
Guides
- Communication error between indoor and outdoor unit: what to check, in which order
Communication (transmission) error codes usually come from the connecting wire, the supply or a board. The checks from easy to hard.