Error code reference

Denso Air Conditioner Error Codes

38 error codes documented with diagnostic procedures.

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ALDetection of unit stop signal from fire alarm system ALRMUnit stop signal detected from fire alarm system ASCondensate pump problem CFLoss of cooling detection DFFreezing abnormality E01WMC room thermistor (RTS1) failure E02Evaporator inlet air thermistor (RTS2) failure E03Condenser inlet air thermistor (ODS) failure E04Condenser thermistor (CTS1) failure E05Evaporator pipe inlet thermistor (CTS2) failure E06Evaporator pipe outlet thermistor (CTS3) failure E07Condensation overflow detected from optional condensate pump E08WMC communication error E09Evaporator fan motor locked E1Room thermistor connection problem E10Condenser fan motor locked E11STI module communication error E14Compressor over current E15Compressor lock failure E16Compressor phase interruption abnormality E17Motor position detection abnormality E18Input overcurrent E19Power device temperature abnormality E2Freeze protection thermistor connection problem E20DC voltage abnormality E21Power device damage abnormality E22Circuit malfunction E4Activation of protective device FLOvercurrent relay (thermal relay) protection activated FTFreeze protection thermistor defect FZDefrost status / freeze condition indicated; evaporator outlet pipe temperature displayed.HPActivation of high pressure switch IREvaporator fan motor reverse rotation abnormality LOCKEDKey lock mode is active OLCompressor overload relay activated due to high temperature build-up in compressor.ORCondenser fan motor reverse rotation abnormality PUCondensation overflow detected RTRoom thermistor defect

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