Fault Codes/Rehlko/27Rehlko27UnclassifiedGeneralWhat This Code MeansAux Switch FaultPossible Causes•Contactor fault•Controller faultRelated Rehlko Fault Codes2829263012313SRCSYSTEMDISABLE330X000134—1—35Browse all Rehlko fault codes→ASK RUDY ABOUT THIS FAULTGet a diagnosis walkthrough for 27 on your specific Rehlko unit — cited to the OEM manual, not a forum guess.Your question about 27GET THE ANSWERFree account required — we'll bring your question with you.