F3 means the dishwasher isn’t heating water correctly during the cycle, usually the heating element or a safety thermostat.
F3 appears when the unit can’t bring water up to the right temperature during the cycle. The heating element or its safety circuit is the main suspect.
The information provided here is a diagnostic aid and does not replace the intervention of a qualified professional.
No cause is certain until it has been checked on the appliance.
An error code varies by brand
The same code can have a different meaning depending on the brand and model. Always check your appliance's manual before acting.
When to call a professional
If the simple checks turned up nothing, if the repair involves electricity, gas, or the sealed refrigerant system, or if you have any doubt at all: stop there and hand the appliance over to a qualified technician.