E919 on a Samsung heat pump: Disinfection Operation Incomplete Error
Short answer
On a Samsung heat pump, E919 means: Disinfection Operation Incomplete Error. The heat pump keeps running. The wording differs by model range — each is shown below.
Reviewed 23 September 2026 · 2 sources
What it means
On the EHS Mono R290 (AE***CXYD*K and pump-integrated AE***CXYB*K)
The manual says: Disinfection Operation Incomplete Error.
Part involved: DHW booster/backup heater and tank sensor (disinfection cycle).
When it shows: Unit self-diagnosis: Disinfection Operation Incomplete Error.
Likely causes:
- Disinfection (legionella) cycle did not reach or hold the set temperature for the required time: booster/backup heater, tank sensor, settings or schedule.
- Engineer checks per Samsung service manual: Check DHW booster/backup heater, DHW tank sensor and disinfection settings (FSV).
On the EHS Mono R32 (AE***RXYD*G)
The manual says: Error that the set temperature for disinfection operation is not reached, or, after reaching, the temperature fails to continue for the requested time.
Part involved: DHW booster/backup heater and tank sensor (disinfection cycle).
When it shows: Unit self-diagnosis: Error that the set temperature for disinfection operation is not reached, or, after reaching, the temperature fails to continue for the requested time.
Likely causes:
- Disinfection (legionella) cycle did not reach or hold the set temperature for the required time: booster/backup heater, tank sensor, settings or schedule.
- Engineer checks per Samsung service manual: Check DHW booster/backup heater, DHW tank sensor and disinfection settings (FSV).
Is it safe?
| Does the heat pump stop? | No |
|---|---|
| Severity | Warning |
The heat pump keeps running.
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; check thermostat/timer and controller operating-mode settings; check the DHW/disinfection schedule has not been interrupted by a power cut or manual change; then contact your installer or Samsung service; Samsung manuals do not describe a homeowner reset for this code.
What the engineer will check
- Check DHW booster/backup heater, DHW tank sensor and disinfection settings (FSV). Any work inside casings, on PCBs, wiring, sensors, pumps, valves or refrigerant is engineer-only.
Who to ask for: Heat pump engineer (DHW/controls).
Certification: G3 unvented hot water qualification if cylinder safety devices are worked on.
What you might notice
What owners and engineers report
1 owner and engineer report mentions this.
- No hot water on the EHS Mono R32 (AE***RXYD*G): 1 report
Sources
- EHS R290 Mono Outdoor Unit Installation Manual AE***CXYD** (EU) DB68-12496A-03 ↗ · DB68-12496A-03 · page p.24 · Reviewed 23 September 2026
- EHS R-32 Mono Outdoor Unit Installation Manual (EU) DB68-08408A-07 ↗ · DB68-08408A-07 · page p.44 · Reviewed 23 September 2026
A code explains what the controller detected, not a confirmed root cause.
Reviewed: 23 September 2026