F08 error, hybrid water heater shows communication or internal control error, may lock out
Safety Warning
This repair may involve working with high voltage components or water connections. Always unplug the appliance before removing any panels.
If you are not confident in your ability to perform this repair safely, we strongly recommend contacting a professional technician.
Possible Causes
How to Fix / Troubleshooting
Safety first: Turn OFF power at the breaker.
Steps to check:
- Remove the front control panel cover to access the user interface (UI) board and main control board.
- Inspect for signs of moisture, condensation, or corrosion on connectors and boards. Dry any moisture and correct the source (leaks, high humidity).
- Disconnect and reconnect the ribbon cable or harness between the UI and main control several times to clean contacts.
- Check that all ground wires are securely attached to the chassis.
Corrective actions:
- If F08 persists, replace the UI board first if Whirlpool service literature recommends it, otherwise replace the main control board.
- Update firmware if Whirlpool provides a service update for your model (typically technician-only).
Note: Some communication errors can be cleared by a full power reset (turn breaker OFF for 5 minutes, then ON), but recurring faults indicate hardware issues.
Repair Difficulty
Required Part
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