Oven heats but temperature is inaccurate; food undercooked or overcooked compared to set temperature.

Safety first: Allow the oven to cool before working on seals or sensors. Isolate power if removing panels.

Steps to check:

• Verify with thermometer: Use an oven-safe thermometer to compare actual temperature to the set temperature at 180°C. Allow at least 20 minutes to stabilise.
• Inspect door seal: Check the rubber gasket around the door for splits, gaps, or hardened sections. Replace if damaged.
• Check door closure: Ensure the door closes firmly and evenly. Adjust hinges or replace hinge receivers if the door is sagging.
• Sensor/thermostat: On electronic models, test the temperature sensor resistance as in F1/F2. On analogue models, a faulty thermostat may cause large deviations and should be replaced.
• Minor offset: Some Rangemaster models allow temperature calibration in the settings menu. Refer to the manual to adjust by ±10–20°C if needed.