Alto-Shaam Combi Oven Error Code E210: VFD Under Voltage
E210 VFD Under Voltage means the table-top or upper fan drive reports an under-voltage condition. Press the Start icon to acknowledge it, and have a technician check the drive and its LED blink code.
High: the fan drive is reporting low voltage and the fan may not run.
- Code
- E210
- Maker
- Alto-Shaam
- Equipment
- Combi ovens
- Applies to
- Combitherm CT PROformance (CTP) and CT Classic (CTC)
What does Alto-Shaam error code E210 mean?
The variable frequency drive, or VFD, that runs the convection fan needs a steady supply and monitors it. If the voltage reaching the drive falls below its limit, the drive reports under voltage and the control posts E210 VFD Under Voltage. The manual lists only one possible cause, a VFD malfunction, and says the blink code on the drive's LED also applies. The drive's own reading is the key, since the supply could be low because of the building, because of a bad connection, or because the drive's measurement is wrong. Pressing Start acknowledges the message and the oven then tries to return to normal operation, but the drive repeats its voltage check each time it starts. E210 refers to the table-top or upper drive. It sits alongside E211, which reports the opposite condition, over voltage, and E212 and the current codes after it.
Affected models and control systems
Combitherm CTP and CTC ovens in electric and gas, sizes 6-10 to 20-20. For a roll-in, E210 reports the table-top or upper drive.
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
- E210 VFD Under Voltage on the display
- Convection fan slow or stopping
- Message appearing when other heavy equipment starts
Possible causes
Listed in Alto-Shaam's documentation
- Possible VFD malfunction
Other likely causes — what usually sits behind error code E210 on this control. A technician confirms which one it is before any part is replaced.
- A loose or corroded connection on the oven's supply lines dropping voltage under load
- Building voltage sagging when large kitchen equipment starts on the same circuit
Safe checks before calling for service
- Press the Start icon once to acknowledge E210.
- Note whether lights or other equipment dimmed or restarted at the same moment.
- Make sure the oven's breaker is fully on and not warm to the touch.
- Tell the technician the time and any other equipment on the same circuit.
How a technician diagnoses error code E210
- Read the code and note any pattern of when it appears.
- Measure the supply voltage at the oven under load.
- Check connections in the supply for heat damage or looseness.
- Read the drive's LED blink code.
- Replace the VFD only if supply and wiring are good.
- Supply voltage measurements are taken on live 208-240 V wiring.
- The drive holds a charge after power is removed.
- A supply problem can damage other equipment as well.
How error code E210 differs from similar codes
E211 is the table-top or upper drive reporting over voltage; E210 is the opposite, under voltage.
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)
- 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
Is E210 a power company problem?
It can be, but the manual lists only a possible drive malfunction.
Does it affect the lower fan?
This code names the table-top or upper drive.
Will it clear on restart?
If the voltage was a one-time dip, perhaps.
Need help with Alto-Shaam error code E210?
A technician confirms the cause on site and gives you the price in writing before any work starts.