Convotherm Combi Oven Error Code E12.1-E12.4: Core Probe Reads High
E12.1, E12.2, E12.3 and E12.4 on the older Convotherm OES, OEB, OGS and OGB ovens mean the core temperature sensor is reading too high. The manual's response is to correct the sensor position. Check where the probe sits first.
Low: only core-probe cooking is affected, and probe placement often fixes it.
- Code
- E12.1 / E12.2 / E12.3 / E12.4
- Maker
- Convotherm
- Equipment
- Combi ovens
- Applies to
- Convotherm OES / OEB / OGS / OGB (older, pre-C4)
What does Convotherm error code E12.1 / E12.2 / E12.3 / E12.4 mean?
The core temperature probe is pushed into the food, and the control uses its reading to decide when a core-temperature program is done. Each of the four codes, E12.1 to E12.4, reports the core temperature sensor reading too high a temperature. The reading is very sensitive to where the probe is: a tip lying against a hot tray, sitting near the surface, or sticking out of the food will read much higher than the true core. The manual's response is exactly that, to correct the sensor position. If the probe is placed correctly and the code stays, the probe, its cable or the connector could be giving a false reading. That is a job for service, because the probe is not something you can test without a meter. The oven keeps its other functions.
Affected models and control systems
Older Convotherm combi ovens in the OES, OEB, OGS and OGB line, which came before the C4. The source is that line's English user manual, a translation of the original, with no revision number printed.
Code numbers and their meaning can change between control generations. We match the full model and control before acting on a code.
What you may notice
- E12.1, E12.2, E12.3 or E12.4 on the display
- Core-temperature program ends early
- Probe tip touching a tray or out of the food
- Reading jumps up quickly
Possible causes
Likely causes — what usually sits behind error code E12.1 / E12.2 / E12.3 / E12.4 on this control. A technician confirms which one it is before any part is replaced.
- Probe tip lying on a hot tray or touching the chamber wall
- Probe pushed in too shallow or sticking out of the food
- Damaged probe cable giving a false reading
- Probe plug not fully seated in the socket
Safe checks before calling for service
- Remove the probe and look at the tip and cable.
- Insert it into the thickest part of the food, tip centered, clear of bone, tray and wall.
- Plug it in fully and start the program again.
- If the code stays with a correctly placed probe, stop using core-probe programs and contact customer service.
- Note which of the four codes appears.
How a technician diagnoses error code E12.1 / E12.2 / E12.3 / E12.4
- Read the code and history.
- Check the probe position and test it in a known temperature.
- Measure the probe resistance against temperature.
- Inspect cable and connector.
- Check the input on the board.
- Replace the probe first, then the board if needed.
- Verifying the probe input on the board needs the cover off.
- A false high reading can be a probe or the board input, which only measurement can separate.
- Probes are precision parts, and a replacement must match the oven.
Technical reference
- Maker documentation
- Convotherm owner support
- Edition
- No revision/part number found in the text read
- Models / control
- Convotherm OES / OEB / OGS / OGB (older, pre-C4)
- Section
- Troubleshooting, Errors and required responses, pp. 161-162
- Checked
- October 2026
We use the maker's document to read the code and do not reproduce it. Always confirm the complete model and control before applying these steps.
Related Convotherm combi oven error codes
What do the four numbers mean?
The manual groups them. The number after the dot names the measuring point, though it gives the same response.
Can I cook without the probe?
Use time-based cooking instead.
Is E12.x about the oven chamber?
No. That is E11.0.
Need help with Convotherm error code E12.1 / E12.2 / E12.3 / E12.4?
A technician confirms the cause on site and gives you the price in writing before any work starts.