Haier 1U71S2SG1FA Service Manual

Also see for 1U71S2SG1FA: Installation manual Service manual Installation manual

Contents

249StartNoYesNo NoYesAs per the wiringdiagram, check ifconnection portbetween sensor andPCB is correctRe-fix thesensor andcheck againCheck if the sensoris in open circuit orthe connection portto PCB is in goodconditionCheck if thesensor resistorvalue is correctReplace sensorand checkagainReplace sensorand checkagainPCB is faultyand repalce it,check againYesTrouble 9: AC current over current protection or current transducer damaged, or compressor blockedrotor, compressor great vibration, compressor abnormal startup, state detecting curcuit abnormal orcompressor damaged.The former twice failure can be resumed automatically, if outdoor board occurs this failure always, andcan not be resumed for a long time, that shows:1. Power module (SPDU) damaged, please replace the power module, then re-wiring as per the wiringdiagram (70% possibility)2. Short circuit in power board results in the power module damaged (15％ possibility)3. Damaged compressor results in this failure (10％ possibility)4. Main control board is faulty, replace it (5％ possibility)Trouble 10: High pressure failureReasons:1. Over high system pressure results that the unit stop, and the compressor protection will work. Thefailure can be resumed.2. Pressure switch wire is not fixed well or in open circuit.StartNoCheck if the connectorbetween pressureswitch and PCB isfixed badly or damagedNo NoNoYes Yes YesCheck if the 2 straightlugs on the pressureswitch are in goodconditionIf outdoor fanmotor cannotstartup normallyin cooling modeReplace maincontrol boardand check againReplace pressure switchconnector, shut off andbe electrified again,re-checkReplace pressureswitch connector, shutoff and be electrifiedagain, re-checkCheck if theoutdoor motorhas power inputReplace outdoormotor and checkagainTrouble 8: Outdoor unit alarms sensor failure