Samsung EHS 554 fault code

What it means

Gas leak error (R290)

The outdoor unit reports a gas leak. On an R290 machine treat this as a live flammable-gas event until your own detector says otherwise. The alarm can be silenced 4 minutes in by holding OK for 3 seconds — silencing is NOT fixing.

Safety: R290 / A3: eliminate ignition sources, ventilate, and sweep with an R290-rated detector BEFORE any other work. Silencing the alarm does not make the unit safe.

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.

Now the harder half: proving what caused it

554 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.