Alto-Shaam Combi Oven Error Code E11: Convection Temperature High
E11 Convection Temperature High means the cavity probe, N6, read above 600 F (315 C) for at least 25 seconds in a combination or convection program. Press the Start icon to acknowledge it, and call for service if it comes back.
High: heat may be running past the safe limit, so the oven should stay off until it is checked.
- Code
- E11
- Maker
- Alto-Shaam
- Equipment
- Combi ovens
- Applies to
- Combitherm CT PROformance (CTP) and CT Classic (CTC); Combitherm CT Express / ESi / CCi (older 4-10 and 4.10 units; boiler or generator electric/gas)
What does Alto-Shaam error code E11 mean?
Convection and combination programs heat the cavity with an element and the circulating fan, and the cavity probe N6 reports the temperature back to the control. The control also keeps a hard ceiling. If N6 reads above 600 F (315 C) for at least 25 seconds, the control posts E11 Convection Temperature High and stops heating. That ceiling is well above any cooking setpoint, so reaching it means the heating is out of control rather than a normal overshoot. The manual names two causes: the convection element contactor is locked on, so the element keeps receiving power when it should be off, or the N6 probe is itself giving a wrong reading. Pressing Start acknowledges the message and the oven then tries to return to normal operation, but a contactor stuck on will push the temperature up again on the next heat call. For that reason the code should not be ignored.
Affected models and control systems
Electric and gas Combitherm CTP and CTC ovens in the six sizes from 6-10 to 20-20. The CT Express manual lists E11 as Convection Temperature High as well.
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
- E11 Convection Temperature High on the display
- Oven interior far hotter than the set temperature
- Heat continuing after a program ends
Possible causes
Listed in Alto-Shaam's documentation
- Convection element contactor locked on
- N6 cavity probe malfunction
Other likely causes — what usually sits behind error code E11 on this control. A technician confirms which one it is before any part is replaced.
- A contactor with welded contacts after repeated heavy cycling
- A shorted or damaged N6 probe cable near the cavity wall that distorts the reading
Safe checks before calling for service
- Press the Start icon once to acknowledge E11.
- Do not open the oven door while it is very hot; wait for it to cool.
- Turn the oven off at its normal switch and note the setpoint and program that was running.
- If E11 returns, leave the oven off and call; do not keep cooking.
How a technician diagnoses error code E11
- Read the code and ask which program and setpoint were running.
- With the oven cool, check the convection element contactor for stuck or burned contacts.
- Measure N6 resistance against the probe chart and compare it with a reference reading.
- Check that the contactor coil is de-energized when no heat is called.
- Replace the contactor or probe only after the test confirms which one failed.
- A contactor that is locked on keeps live 208-240 V on the heating element.
- The cavity can exceed 600 F (315 C), so tests need the oven cooled and then powered with care.
- Replacing high-current contactors needs correct torque and wire sizing.
How error code E11 differs from similar codes
E11 covers high cavity temperature in convection or combination use, while E13 covers the steam generator and E02 covers the relay board.
Technical reference
- Maker documentation
- Alto-Shaam owner support
- Edition
- MN-35949 Rev 08 03/22
- Models / control
- Combitherm CT PROformance (CTP) and CT Classic (CTC); Combitherm CT Express / ESi / CCi (older 4-10 and 4.10 units; boiler or generator electric/gas)
- Section
- Error Codes, pp. 25-31
- 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 Alto-Shaam combi oven error codes
How hot is too hot for E11?
The control posts it when N6 reads above 600 F (315 C) for at least 25 seconds.
Can a bad probe cause E11?
Yes, N6 is one of the two listed causes, so a false reading is possible.
Is it safe to keep cooking?
Not until the cause is found, since a stuck contactor can overheat the cavity.
Need help with Alto-Shaam error code E11?
A technician confirms the cause on site and gives you the price in writing before any work starts.