Safety first: Isolate the oven from the mains. Cooling fans can start unexpectedly when power is applied.

Check fan operation: With the oven cool, gently spin the cooling fan blades (usually located behind the top rear panel). They should rotate freely without scraping.
Inspect wiring: Remove the top or rear cover to access the cooling fan motor. Check the connector and wiring for heat damage or loose connections.
Test fan motor: With power off, measure resistance across the fan motor terminals. An open circuit indicates a failed motor. If you are qualified, you can also test the fan with a separate power source of the correct voltage.
Control board output: If the fan motor is good but never runs or runs constantly, the control PCB fan driver (relay or triac) may be stuck. This typically requires PCB replacement.
Replace faulty parts: Fit a new AGA cooling fan motor if seized or open. Replace the main control PCB if the fan output is not being controlled correctly.

AGA oven shows F8 and cooling fan may run continuously; oven may not start.

Possible Causes