Oven does not reach set temperature, takes very long to heat, undercooks food

Safety first: Isolate the oven from mains power before removing panels or accessing wiring.

• Verify actual temperature: Place an accurate oven thermometer in the center of the cavity. Set the oven to 200°C and allow 20–30 minutes. Compare the displayed temperature to the thermometer. If the difference is large (±30°C or more), proceed with checks.
• Check elements: Inspect the circular fan element and bottom element for hot spots, cracks, or partial burn-through. Test resistance with a multimeter; a significantly higher resistance than spec can indicate a weak element. Replace any suspect element.
• Inspect door gasket: Check the Fagor door seal all around for gaps, tears, or hardened sections. Close the door on a sheet of paper; it should grip firmly all around. Replace the gasket if loose or damaged.
• Test temperature sensor: Remove and measure the NTC sensor resistance at room temperature and at a known warm temperature (e.g., 100°C in hot water, disconnected). If readings are unstable or far from expected values, replace the sensor.
• Control calibration: Some Fagor models allow temperature offset calibration in the settings menu. Consult the user manual to adjust if the oven is consistently off by a fixed amount. If calibration does not help, the control board may need replacement.