Error code
GE / Water heater
F21
Application update failed.
What it means
Application update failed.
This explanation is shared only by models whose manufacturer documents the same code, meaning, and guidance.
Manufacturer guidance
- Arrange GE Appliances service and provide the displayed code.
Manufacturer source
Models documented with this signal
Select your exact model below to open its manufacturer source. Manual editions and model revisions can differ.
If there is a safety risk, stop using the appliance and follow the manufacturer’s instructions.