Samsung EHS 904 fault code
Samsung EHS heat pumps
What it means
DHW tank temperature sensor error
The dhw tank sensor sensor reads open or short circuit.
Safety: Safe isolation before disconnecting sensors or working on the PCB.
UK models this code applies to
From the Samsung service literature we hold (Samsung MWR-WW10N user & service manual DB68-08470A-17 (Appendix: error codes)) — not a scraped list.
EHS Mono R290 5 kW (AE050CXYD)EHS Mono R290 8 kW (AE080CXYD)EHS Mono R290 12 kW (AE120CXYD)EHS Mono R290 16 kW (AE160CXYD)EHS split AE040JXEDEH/EUEHS split AE060JXEDEH/EUEHS split AE090JXEDEH/EUEHS split AE120JXEDEH/EUEHS split AE140JXEDEH/EUEHS split AE160JXEDEH/EUEHS split AE090JXEDGH/EUEHS split AE120JXEDGH/EUEHS split AE140JXEDGH/EUEHS Split R32 AE040RXEDEG/EUEHS Split R32 AE060RXEDEG/EUEHS Split R32 AE090RXEDEG/EUEHS Split R32 AE090RXEDGG/EU
Now the harder half: proving what caused it
904 names a symptom, not a root cause. In the app, the same code opens a guided investigation: what to measure first, the expected values for your exact model, and an honest verdict — including “nothing in this machine is broken” when that's what the readings say.
Chase 904 on your machine →Free, no sign-up. Pick the model and follow Samsung EHS's own chart for it, one question at a time.
Or watch one get chased — free demo →