Error code reference
Samsung Heat Pump Error Code E120
Communication error between indoor unit and outdoor unit (pre-tracking failure or different unit number…
Communication error between indoor unit and outdoor unit (pre-tracking failure or different unit number between set units and indoor units).
First step from the service manual
1
Compare the setting switch's setup value for indoor unit installation number on the outdoor unit PCB with the actual number.
The complete diagnostic procedure includes additional test steps, resistance specifications, wiring diagram references, and component test points.
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E120 on my Samsung Heat Pump
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Communication error between indoor unit and
From Service Manual 326064, p.36:
1.Compare the setting switch's setup value for indoor unit installation number on the outdoor unit PCB with the actual number.
2.Measure door lock assembly resistance across the PTC terminals. Expected: ~200 ohms cold, rising sharply once energized.
3.Inspect strike and latch alignment. A warped door or misaligned strike prevents the switch stack from closing in the correct sequence.
Part DC34-00024B
Door lock assembly
Related Samsung heat pump codes
All Samsung heat pump codes →- ChCompressor preheating in progress
- E101Outdoor temperature sensor open or short circuit.
- E102Compressor down by high pressure protection control
- E103Fixed compressor 1 discharge temperature sensor open or…
- E104Compressor down by low pressure protection control
- E105Fixed compressor 3 discharge temperature sensor open or…
- E106High pressure sensor open or short circuit.
- E107Low pressure sensor open or short circuit.
View all 154 Samsung heat pump codes
- E108Compressor 1 sump temperature sensor open or short circuit.
- E109COND OUT sensor open or short circuit.
- E110Oil balance sensor 1 open or short circuit.
- E111Suction sensor open or short circuit.
- E112Double pipe sensor open or short circuit.
- E113Reverse phase or missing phase detected on 3-phase power.
- E114Instant power off error
- E115Forbid heat mode operation when outdoor temperature is over…
- E116Prohibit starting by low pressure
- E117Forbid operation by low pressure
- E118Equal oil valve 1 self diagnosis error (open or close…
- E119Communication error between indoor and outdoor unit (when…
- E121Detection of reverse phase or missing phase of 3-phase power
- E122Compressor down by indoor unit freezing protection control
- E123Compressor down by low pressure protection control
- E124Compressor down by indoor unit freezing protection control
- E125Forbid operation due to low pressure
- E126Equal oil valve 1 self-diagnosis error (open or close…
- E127Compressor down by discharge temperature sensor
- E128Outdoor temperature sensor error
- E129Suction temperature sensor breakaway
- E130COND MID temperature sensor error (open/short) on outdoor…
- E131Digital compressor discharge temperature sensor error…
- E132Constant speed compressor 1 discharge temperature sensor…
- E133Constant speed compressor 2 discharge temperature sensor…
- E134Oil temperature sensor error (open/short).
- E135Equal oil temperature sensor error (open/short).
- E136Dual-pipe temperature sensor error (open/short).
- E145Compressor sump temperature protection control
- E151Instant power-off error
- E152Fan motor RPM error
- E153Fan motor IPM high temperature error
- E154Prohibit compressor starting due to outdoor temperature…
- E155Communication error between indoor and outdoor unit during…
- E156Communication error between main outdoor unit and sub MICOM…
- E157Switch option setting error (not applied).
- E158Compressor down by compression ratio control
- E159Fan motor over current error
- E160Prohibit compressor start due to outdoor temperature out of…
- E161Loading failure of digital compressor or OLP trip detected…
- E185Compressor low current error
- E186Compressor over current error
- E2Tracking error
- E201Tracking error
- E201_commCommunication error between indoor unit and outdoor unit…
- E202Compressor down by low pressure protection control
- E203Compressor down by indoor unit freezing protection control
- E204Compressor down by sump temperature protection control
- E205Loading failure.
- E206Compressor down by discharge temperature sensor
- E207COND OUT sensor breakaway detected during heating operation…
- E208Suction temperature sensor breakaway
- E251Digital compressor discharge temperature sensor breakaway
- E252Fixed 1 compressor discharge temperature sensor breakaway.
- E253Fixed 2 compressor discharge temperature sensor breakaway.
- E254Fixed 3 compressor discharge temperature sensor breakaway…
- E262Compressor discharge temperature sensor breakaway
- E263Compressor discharge temperature sensor breakaway
- E264Compressor discharge temperature sensor breakaway
- E301Fan motor high temperature error
- E302Low pressure sensor error (open/short)
- E303Fan motor IPM high temperature error
- E304CT over-current error
- E305Fan motor reverse rotation error
- E401COND OUT sensor breakaway detected during heating operation
- E402Indoor heat exchanger EVAP IN sensor breakaway
- E403Compressor down by compression ratio control
- E404Compressor sump temperature (oil temperature) sensor…
- E405CT low current error
- E406Suction temperature sensor breakaway
- E412Compressor down by high pressure protection control
- E415Compressor down by low pressure protection control
- E416Prohibit starting by low pressure
- E422Oil valve (equal oil valve) 1 self diagnosis error
- E425Detection of reverse phase or missing phase of 3-phase power
- E440Compressor down by indoor unit freezing protection control
- E441Compressor sump temperature protection control
- E442Compressor down by compressor discharge temperature sensor…
- E461Detection of floating switch of indoor unit drain pump (1st…
- E462Outdoor unit fan motor RPM error
- E463Indoor unit EVAP OUT sensor open or short error.
- E464Outdoor unit fan motor IPM high temperature error
- E465Compressor over current error (compression ratio)
- E466Compressor low current error
- E467Indoor unit EEV close failure (2nd detection)
- E468Digital compressor loading failure or OLP trip detected
- E469Indoor unit EVAP IN sensor breakaway detected via…
- E470Indoor unit EVAP OUT sensor breakaway detected via…
- E471Instant power-off error
- E472Indoor unit EV close error (2nd detection)
- E473Indoor unit EEV open failure (2nd detection)
- E474Indoor unit EVAP IN sensor breakaway detected during…
- E475Indoor unit EVAP OUT sensor breakaway detected during…
- E476Digital compressor 1 sump temperature sensor breakaway
- E477Fixed compressor 1 sump temperature sensor breakaway.
- E478Fixed compressor 2 sump temperature sensor breakaway.
- E479Fixed compressor 3 sump temperature sensor breakaway.
- E480Fixed compressor 1 discharge temperature sensor breakaway.
- E481Indoor unit EV open error (1st detection)
- E482Indoor unit EV open error (2nd detection)
- E483Fixed compressor 2 sump temperature sensor breakaway.
- E484Fixed compressor 3 sump temperature sensor breakaway.
- E485Fixed compressor 1 discharge temperature sensor breakaway
- E486Fixed compressor 2 discharge temperature sensor breakaway.
- E487Fixed compressor 3 discharge temperature sensor breakaway.
- E501Oil valve (equal oil valve) 1 self-diagnosis error
- E502Indoor unit EVAP IN sensor error (open/short).
- E503Indoor unit EVAP OUT sensor error (open/short).
- E504Indoor unit outlet temperature sensor error (open/short)
- E508Outdoor temperature sensor error (open/short).
- E509Digital compressor discharge temperature sensor error…
- E511Oil collection operation in progress
- E512Constant speed compressor discharge temperature sensor…
- E513High pressure sensor error (open/short).
- E514Low pressure sensor error (open/short).
- E515Oil temperature sensor error (open/short).
- E516Equal oil temperature sensor error (open/short).
- E517COND OUT temperature sensor error (open/short).
- E518Dual-pipe temperature sensor error (open/short).
- E519COND MID temperature sensor error (open/short) on outdoor…
- E551Indoor heat exchanger EVAP IN sensor breakaway
- E552Indoor heat exchanger EVAP OUT sensor breakaway
- E554Compressor sump temperature (oil temperature) sensor…
- E556Detection of floating switch of indoor unit drain pump (1st…
- E557Detection of floating switch of indoor unit drain pump (2nd…
- E558Suction temperature sensor breakaway
- E561Digital compressor discharge temperature sensor breakaway
- E562Fixed 1 compressor discharge temperature sensor breakaway.
- E563Fixed 2 compressor discharge temperature sensor breakaway…
- E564Fixed 3 compressor discharge temperature sensor breakaway…
- E601Oil collection operation mode
- E602Indoor unit EV close error (1st detection)
- E603Indoor unit EV close error (2nd detection)
- E604Indoor unit EV open error (1st detection)
- E605Indoor unit EV open error (2nd detection)
- P4Reverse phase or missing phase error detected on 3-phase…
- P466Indoor unit floating switch error (1st detection)
- P467Indoor unit EEV close failure (1st detection).
- P468Indoor unit EEV open failure (1st detection).
- P471Indoor unit floating switch error (1st detection)
- P472Indoor unit EEV close failure (1st detection)
- P473Indoor unit EEV open failure (1st detection)
- U200Communication error between outdoor unit main and sub MICOM…
- U201Communication error between outdoor unit main and sub MICOM…
- U202Communication error between outdoor unit main and sub MICOM…
- U203Communication error between outdoor unit main and sub MICOM…
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