Can I clear the F18 code myself?

It depends on the severity. Warning-level codes can usually be cleared by following the recommended fix. Fault and critical codes often require checking the source condition first; if the code returns immediately after restart, escalate to authorized service.

Is the F18 fix the same on every device?

The cause is consistent — it's the same protection logic. The exact fix wording can differ per device because each official manual addresses model-specific context (input ranges, parallel-config notes, firmware revisions). Use the per-device section that matches your unit.

Where does this information come from?

Every entry is sourced directly from the official Felicity user manual for the affected device. The "Source" line at the bottom of each device's section shows the manual filename and page number.

Fault

F18

Q: What does F18 mean on IVEM 6048?

Fault: Over temperature happen at PV circuit. Cause: The temperature of internal PV converter component is over the limitation. Recommended fix: Check whether the air flow of the unit is blocked or whether the ambient temperature is too high.

Q: What does F18 mean on IVEM8048-II?

Fault: Over temperature happen at PV circuit. Cause: The temperature of internal PV component is over the limitation. Recommended fix: Check whether the air flow of the unit is blocked or whether the ambient temperature is too high.

Q: What does F18 mean on IVEM8048-LV?

Over temperature happen at PV circuit. Cause: The temperature of internal PV component is over the limitation. Recommended fix: Check whether the air flow of the unit is blocked or whether the ambient temperature is too high.

Q: What does F18 mean on T-REX-10KLP3G01?

The output overcurrent is abnormal. Recommended fix: Restart the unit, if the error persists, contact the repair center.

Over temperature happen at PV circuit.

5 Devices that report this code

What does the F18 error code mean?

F18 on a Felicity unit indicates: Over temperature happen at PV circuit.. It is a fault-severity event that can appear on 5 different devices in the Felicity catalog. The same code may have slightly different recommended fixes depending on the device — the per-device sections below show the exact wording from each device's official manual.

This is a fault-severity code

Fault codes stop normal operation but the unit may attempt to recover. Common causes are out-of-range conditions (voltage, current, temperature) that require checking inputs and outputs before restart.

What triggers this code

F18 is triggered when the unit's protection or monitoring logic detects the specific condition described above. The exact trigger depends on the device — see the per-device sections for the official manual entry for each.

IVEM 6048Inverter↗ view on device

F18Over temperature happen at PV circuit.Fault

Description

Fault: Over temperature happen at PV circuit.

Cause

The temperature of internal PV converter component is over the limitation.

Recommended fix

Check whether the air flow of the unit is blocked or whether the ambient temperature is too high.

Source:felicitysolar IVEM 6048 Solar Inverter User Guide.pdf · page 37

IVEM8048-IIInverter↗ view on device

F18Over temperature happen at PV circuit.Fault

Description

Fault: Over temperature happen at PV circuit.

Cause

The temperature of internal PV component is over the limitation.

Recommended fix

Check whether the air flow of the unit is blocked or whether the ambient temperature is too high.

Source:IVEM8K-12K-II_compressed.pdf · page 43

IVEM8048-LVInverter↗ view on device

F18Over temperature happen at PV circuit.Fault

Description

Over temperature happen at PV circuit.

Cause

The temperature of internal PV component is over the limitation.

Recommended fix

Check whether the air flow of the unit is blocked or whether the ambient temperature is too high.

Source:FelicitySolar IVEM8048-LV Single Phase Hybrid Inverter User Guide.pdf · page 38

T-REX-10KLP3G01Inverter↗ view on device

F18The output overcurrent is abnormal.Fault

Description

The output overcurrent is abnormal.

Recommended fix

Restart the unit, if the error persists, contact the repair center.

Source:T-REX-10KLP3G01-Inverter-User-Guide.pdf · page 28

T-REX-50KHP3G01Inverter↗ view on device

F18Battery 1 Undervoltage fault.Fault

Description

Battery 1 voltage is too low, the battery should be charged.

Source:T-REX-50KHP3G01-user-manual-.pdf · page 46

Frequently asked about F18

What is the F18 error on Felicity?: F18 on a Felicity unit means: Over temperature happen at PV circuit.. It can appear on 5 different devices in the Felicity catalog. The cause and recommended fix are listed for each device on this page.
Can I clear the F18 code myself?: It depends on the severity. Warning-level codes can usually be cleared by following the recommended fix. Fault and critical codes often require checking the source condition first; if the code returns immediately after restart, escalate to authorized service.
Is the F18 fix the same on every device?: The cause is consistent — it's the same protection logic. The exact fix wording can differ per device because each official manual addresses model-specific context (input ranges, parallel-config notes, firmware revisions). Use the per-device section that matches your unit.
Where does this information come from?: Every entry is sourced directly from the official Felicity user manual for the affected device. The "Source" line at the bottom of each device's section shows the manual filename and page number.

Compiled from official Felicity user manuals. Always consult your device manual and a qualified technician before performing repairs.