Coreco E5 Error Code
Carel RTN400 controller — Probe Pb5 faulty (measured values outside operating range or probe fau
Source: Coreco_rtn400_instruction_sheet_9is24288-1_rel0413_en_termostatos.pdf
What does Coreco E5 mean?
On the Coreco controller (Carel RTN400), E5 is probe Pb5 faulty (measured values outside operating range or probe faulty/short-circuited/open); label E5 displayed, alarm icon permanently on.
Symptoms
- Display shows E5
- Alarm icon permanently on
- The reading from the named probe is unavailable
Common causes
- Probe reading outside the operating range
- Probe short-circuited
- Probe open circuit / broken wire
- Loose or corroded probe terminal
- Faulty probe element
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Diagnostic steps
Identify the affected probe
E5 reports the named probe as faulty (reading out of range, short-circuited or open). Note which probe input it maps to on this unit.
Inspect the probe wiring
With power isolated, check the probe's lead and connector for an open or short-circuit and reseat any loose/corroded terminal.
Verify and replace the probe
Confirm the correct NTC probe type; if wiring is sound, replace the probe. The alarm clears once the controller reads it in range.
When to call a professional
Electrical access is reserved for qualified personnel; if the wiring is sound have a qualified refrigeration technician replace the probe and re-verify regulation.
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Other Coreco Error Codes
Control probe (probe 1) error — signal interrupted, short-circuited or incompatible probe
Evaporator / defrost probe (probe 2) error — signal interrupted, short-circuited or incompatible probe
Condenser / product probe (probe 3) error — signal interrupted, short-circuited or incompatible probe
Immediate or delayed alarm from the multifunction digital input (external alarm)
Open-door alarm from the door-switch digital input
Low-temperature alarm — measured temperature below set point by more than parameter AL
High-temperature alarm — measured temperature above set point by more than parameter AH
Unit parameter reading (data) error — saved configuration data error
Operating parameter reading (data) error — manual reset
Defrost ended by timeout — last defrost stopped on maximum duration, not on temperature
Defrost running — status message shown during a defrost cycle (not an alarm)
Dirty-condenser warning/alarm — pre-alarm (cht) between Ac-AE and Ac, then alarm (CHt) when Ac is exceeded and refrigeration stops (manual reset)
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