Carel E18 Error Code
Evaporator fan A40 Reference voltage not valid E19 Condenser fan A41 Overtempera
Source: 050002745.pdf
What does Carel E18 mean?
E18 on the Carel Heosone controller (also referenced in propane plug-in cabinet documentation) is an evaporator fan fault alarm. The Heosone monitors the evaporator fan to ensure adequate airflow across the evaporator coil for correct product cooling. When the controller detects the fan has stopped or is not operating within its expected range, E18 activates. Without evaporator airflow, the cabinet temperature rises and stored product is at risk.
Symptoms
- E18 displayed on the Heosone user terminal.
- Evaporator fan is stopped or running at reduced speed.
- Cabinet temperature begins rising as cold air circulation is lost.
- Alarm resets automatically once the evaporator fan resumes normal operation.
- Buzzer sounds and alarm LED flashes.
Common causes
- Evaporator fan motor winding failure — open circuit or seized bearing.
- Fan blade blocked by accumulated ice, debris, or product packaging stacked too close to the evaporator.
- Electrical supply to the evaporator fan motor interrupted — blown fuse, loose connector, or broken wire.
- Inverter or speed-control module driving the fan has faulted.
- Fan speed feedback signal out of range, causing the controller to detect a non-responding fan.
Ask the AskWhiz AI about Carel E18
AskWhiz
online
Diagnostic steps
Confirm the evaporator fan has stopped
Open the cabinet and listen or observe for evaporator fan operation. If stopped with the compressor running, the fault is confirmed. Check whether ice accumulation on the evaporator coil is blocking the fan blade.
Defrost if ice-blocked
If ice has blocked the evaporator fan, switch the cabinet to defrost mode or power off and allow the ice to melt. Once clear, restart and verify the fan runs freely. Excessive icing often indicates a separate defrost control issue that also needs attention.
Check for product or packaging obstruction
Ensure no products are packed against the evaporator grille or fan guard. Airflow restrictions cause ice build-up and eventual fan stall on propane plug-in cabinets.
Inspect fan motor wiring
With the cabinet isolated from mains, trace the fan motor supply wiring. Check terminal connections at the fan motor and at the controller output. A disconnected or burnt-through conductor is a common cause of E18.
Test the fan motor and replace if defective
Measure winding resistance across the fan motor terminals. An open or near-zero reading confirms motor failure. Replace with a compatible DC fan motor of the correct voltage and current rating for the Heosone platform.
When to call a professional
Heosone controllers are used in R290 (propane) plug-in refrigeration units. Propane is flammable — any service involving the refrigerant circuit must be performed by a technician certified for flammable refrigerant handling per the relevant national standard (e.g., EN 378-4, IEC 60335-2-89). For evaporator fan replacement on propane units, ensure the area is ventilated and free of ignition sources before opening the cabinet for service.
Stop searching through PDFs. Our AI assistant on WhatsApp is trained on official Carel documentation and can diagnose this fault code and guide you through the repair in minutes.
5 free questions per bot in your browser — no signup.
Other Carel Error Codes
not active ON probe 2 error= defrost automatic d0= 0 /1 / 4,F0= 1 E2 not active
active ON external alarm automatic [A4 = 1] [+A7] √ √ dOr active ON open door al
active ON low temperature alarm automatic [AL] [Ad] √ HI active ONhigh temperatu
not active ON unit parameter error not possible not active ON operating paramete
Probe S2 fault OFF OFF automatic unchanged unchanged unchanged changed un- YES N
Probe S3 fault OFF OFF automatic unchanged unchanged unchanged changed YES NO ch
Serial probe S11 OFF OFF automatic duty seting (c4)unchanged unchanged un- YES N
Serial probe S12 not updated OFF OFF automatic duty setting (c4) unchanged uncha
Serial probe S13 not updated OFF OFF automatic duty setting (c4) unchanged uncha
Serial probe S14 OFF OFF automatic duty setting (c4)unchanged unchanged un- YES
High temperature A ON ON automatic unchanged unchanged unchanged un- YES NO LO2
(rated current not reached) DRAIN ALARM E5 3 FILL ALARM 卡 MAINTENANCE WARNING (p
Sources: www.carelusa.com
AskWhiz Playground
Test your diagnostic skills
Play a real HVAC service call in the AskWhiz Playground — real brands, real fault codes, no signup.
Play a real service call