E602 on a Samsung heat pump: Wired remote controller Main/Sub setting error
Short answer
On a Samsung heat pump, E602 means: Wired remote controller Main/Sub setting error. The heat pump keeps running. An engineer is needed to fix the cause. The wording differs by model range — each is shown below.
Reviewed 23 September 2026 · 2 sources
What it means
On the EHS Mono R32 (AE***RXYD*G)
The manual says: Wired remote controller Main/Sub setting error.
Part involved: Wired remote controller / AI Home controller.
When it shows: Unit self-diagnosis: Wired remote controller Main/Sub setting error.
Likely causes:
- Wired remote controller communication, setting, sensor or memory fault; controller wiring (F3/F4) fault.
- Engineer checks per Samsung service manual: Follow Samsung service manual troubleshooting for this code.
On the EHS Mono (R410A, AE***JXYD*H)
The manual says: Wired remote controller Master/Slave setting error.
Part involved: Wired remote controller / AI Home controller.
When it shows: Unit self-diagnosis: Wired remote controller Master/Slave setting error.
Likely causes:
- Wired remote controller communication, setting, sensor or memory fault; controller wiring (F3/F4) fault.
- Engineer checks per Samsung service manual: Follow Samsung service manual troubleshooting for this code.
Is it safe?
| Does the heat pump stop? | No |
|---|---|
| Severity | Warning |
| Engineer needed? | Yes |
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; then contact your installer or Samsung service; Samsung manuals do not describe a homeowner reset for this code.
What the engineer will check
- Follow Samsung service manual troubleshooting for this code. Any work inside casings, on PCBs, wiring, sensors, pumps, valves or refrigerant is engineer-only.
Who to ask for: Heat pump engineer (controls).
Certification: Competent electrical worker (BS 7671).
What you might notice
What owners and engineers report
8 owner and engineer reports mention this.
- Controller / thermostat problem on the EHS Mono R32 (AE***RXYD*G): 7 reports
- Controller / thermostat problem on the EHS Mono (R410A, AE***JXYD*H): 1 report
Sources
- EHS R-32 Mono Outdoor Unit Installation Manual (EU) DB68-08408A-07 ↗ · DB68-08408A-07 · page p.44 · Reviewed 23 September 2026
- EHS Mono Outdoor Unit (R410A, AE***JXYD*H) Installation Manual DB68-05387A-07 ↗ · DB68-05387A-07 · page p.39 · Reviewed 23 September 2026
A code explains what the controller detected, not a confirmed root cause.
Reviewed: 23 September 2026