E557 on a Samsung heat pump: Option code miss matching among the indoors (only for DPM)
Short answer
On a Samsung heat pump, E557 means: Option code miss matching among the indoors (only for DPM). The heat pump stops until the fault clears or is reset. An engineer is needed to fix the cause.
Reviewed 23 September 2026 · 1 source
What it means
The manual says: Option code miss matching among the indoors (only for DPM).
Part involved: Hydro unit/control kit and outdoor PCB communication.
When it shows: Unit self-diagnosis: Option code miss matching among the indoors (only for DPM).
Likely causes:
- Communication/addressing fault between hydro unit (control kit) and outdoor unit, or between outdoor PCBs: wiring fault, loose connector, incorrect setting, electrical interference or PCB failure.
- Engineer checks per Samsung service manual: Option setting data wrong: check option codes (per Samsung SM).
Is it safe?
| Does the heat pump stop? | Yes |
|---|---|
| Engineer needed? | Yes |
The heat pump stops until the fault clears or is reset.
Resetting itself: unknown.
Manual reset: unknown.
What you can check
- Note the full error code shown on the controller; check the heat pump breaker/isolator in the consumer unit is ON; then contact your installer or Samsung service; Samsung manuals do not describe a homeowner reset for this code.
What the engineer will check
- Option setting data wrong: check option codes (per Samsung SM). Any work inside casings, on PCBs, wiring, sensors, pumps, valves or refrigerant is engineer-only.
Who to ask for: Heat pump engineer (Samsung-trained, controls/electrical).
Certification: Competent electrical worker (BS 7671) for work on live equipment.
What you might notice
Sources
- Samsung EHS TDM Plus Service Manual Code AC-07002A_0 (Feb 2017) ↗ · AC-07002A_0 · page p.89 · Reviewed 23 September 2026
A code explains what the controller detected, not a confirmed root cause.
Reviewed: 23 September 2026