--- title: "Oven runs hot" description: "La Cornue oven runs hot — an oven that has drifted upwards over years, and a cook who has quietly rewritten every recipe around it." url: "https://la-cornuemiami.support/symptoms/oven-runs-hot/" date_modified: "2026-09-03" Appliance type: "Ovens, Ranges" --- # La Cornue oven runs hot ### One reading is not a measurement Put a thermometer on the middle shelf, set 350 °F and leave it for forty minutes, reading it every ten. What matters is not a single number but the pattern: how far it overshoots on the way up, and what it settles at. An oven that spikes to 425 °F and settles at 350 °F is behaving normally and is a cooking-technique conversation. An oven that settles at 390 °F has drifted, and that is a repair. ### What it usually means, by the kind of La Cornue appliance La Cornue sells one appliance in several forms, and the same behavior points at different things on each of them. A built-in side-by-side and an integrated column are not the same service situation, and a dual-fuel range and an induction range fail in different halves. - **Château vaulted gas oven** — A mechanical thermostat with a dial. Drift here is gradual and measurable. - **Château vaulted electric oven** — Thermostat or sensor. An electric oven that overshoots badly is often the sensor rather than the thermostat. - **CornuFé and Tourelle** — Electronic control with a sensor. Drift is less common and a stuck reading is more common. ### The consequence nobody warns people about An oven that has run 30 °F hot for three years has a cook who has adapted to it completely — shorter times, lower settings, recipes annotated in pencil. Putting the oven back to specification is the correct repair and it will make their next fortnight of baking wrong, because every learned adjustment is now an error in the other direction. We say this before we do the work rather than after, and we leave the before and after measurements in the report so there is a record of exactly what changed. ### Why calibration is not always the answer Some thermostats on this make can be adjusted and some cannot, and even where adjustment is possible, a thermostat that has drifted a long way has usually drifted because it is wearing rather than because it was set wrong. Adjusting a failing thermostat buys a season. So the report distinguishes the two: calibrated, with the figures; or replaced, with the reason. On a dual-fuel range remember that each oven has its own thermostat and they drift independently, so a range can have one oven perfect and the other well out. A drifted thermostat The manual's own explanation, and the finding in most of these cases. Some adjust; many do not come back. A sensor reading low The oven is not lying to you on purpose — it genuinely believes it is cooler than it is. A broil element cutting in during baking On the electric side, it shows as scorching from above and a high average. A control that no longer modulates It heats full and cuts, rather than tapering. Wide swings around a high average. A misread dial or a slipped knob Rare and worth ruling out, because it costs nothing. Measure over forty minutes Every ten minutes. The pattern is the diagnosis. Note the overshoot separately Spike then settle is normal. Settling high is not. Check the dial and knob A knob that has slipped on its shaft reads wrong and costs nothing to find. Ask how long it has been like this Years of gradual drift and a sudden change point at different parts. Everything cooks faster than it should What it usually means The maker's own guide names this and names the answer Measured through a full cycle, not with one reading A corrected oven changes your cooking — expect that One reading is not a measurement Put a thermometer on the middle shelf, set 350 °F and leave it for forty minutes, reading it every ten. What matters is not a single number but the pattern: how far it overshoots on the way up, and what it settles at. An oven that spikes to 425 °F and settles at 350 °F is behaving normally and is a cooking-technique conversation. An oven that settles at 390 °F has drifted, and that is a repair. What it usually means, by the kind of La Cornue appliance La Cornue sells one appliance in several forms, and the same behavior points at different things on each of them. A built-in side-by-side and an integrated column are not the same service situation, and a dual-fuel range and an induction range fail in different halves. Château vaulted gas oven — A mechanical thermostat with a dial. Drift here is gradual and measurable. Château vaulted electric oven — Thermostat or sensor. An electric oven that overshoots badly is often the sensor rather than the thermostat. CornuFé and Tourelle — Electronic control with a sensor. Drift is less common and a stuck reading is more common. The consequence nobody warns people about An oven that has run 30 °F hot for three years has a cook who has adapted to it completely — shorter times, lower settings, recipes annotated in pencil. Putting the oven back to specification is the correct repair and it will make their next fortnight of baking wrong, because every learned adjustment is now an error in the other direction. We say this before we do the work rather than after, and we leave the before and after measurements in the report so there is a record of exactly what changed. Why calibration is not always the answer Some thermostats on this make can be adjusted and some cannot, and even where adjustment is possible, a thermostat that has drifted a long way has usually drifted because it is wearing rather than because it was set wrong. Adjusting a failing thermostat buys a season. So the report distinguishes the two: calibrated, with the figures; or replaced, with the reason. On a dual-fuel range remember that each oven has its own thermostat and they drift independently, so a range can have one oven perfect and the other well out. ### Can I just set it 25 degrees lower and forget about it? You can, and plenty of people do for years. Two arguments against. First, a drifting thermostat rarely stops drifting, so the offset you learn this year is wrong next year and you are permanently chasing it. Second, and more practically, the top of the range matters: an oven that reads 350 °F and delivers 390 °F has no headroom left at 500 °F, so anything that needs real heat gets it and anything delicate is unpredictable. It is a genuine repair with a genuine benefit. ### It burns things on the bottom specifically. That is more likely to be a heat-distribution problem than a calibration one, and on a vaulted oven it has a couple of specific causes worth checking before a thermostat is blamed. A tray larger than the specified size blocks what circulation the cavity has. A range out of level puts the food closer to one radiating surface — the maker's own test is a dish of water on the shelf sitting at one depth all over. And on the gas side, the burner is beneath, so scorching underneath with a correct average points at the burner or the diffuser rather than at the control. --- **[Read full article: Oven runs hot](https://la-cornuemiami.support/symptoms/oven-runs-hot/)**