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Error code reference

Samsung Heat Pump Error Code E121

Detection of reverse phase or missing phase of 3-phase power - phase order reversed or one/all phase voltages not present.

SourceSamsung Heat Pump - Service Manual: Troubleshooting Guide (AVXCMH036EA)p. 12-44

Samsung codesSamsung heat pump codes
Diagnostic procedure

The full E121 procedure

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MyPros+ · DiagnosticsStep 1 preview
1
First diagnostic step
Check power of 3-phase detection part on outdoor unit PCB; verify voltage between CN82 power cable terminals (red-white/white-black/red-black) is approximately 380V.

SourceSamsung Heat Pump - Service Manual: Troubleshooting Guide (AVXCMH036EA)p. 12-44

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Where this code is documented

12 manuals in the MyPros+ library document this code for Samsung heat pump.

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