Error Code
high
Unox OVEN – Control Panel or USB Board Defective – Buzzer Does Not Sound
On your CHEFTOP and BAKERTOP MIND.Maps™ unit, a non-sounding buzzer often indicates…
Unox OVEN - Circuit Breaker Triggers When Control Board Reboots
Critical / Stop Operation
Warning: The information provided here is for educational purposes only.
Working with commercial kitchen equipment involves high voltage, gas, and high temperatures.
We strongly recommend contacting a certified service technician for any repairs.
We are not responsible for any damage or injuries resulting from DIY repair attempts.
This information is provided 'as is' without any guarantees of completeness or accuracy.
TLDR
On your CHEFTOP and BAKERTOP MIND.Maps™ unit, a tripping circuit breaker during control board reboot indicates a short circuit within a component. The most common cause is a shorted 230 V AC back-cooling fan. Immediately replace the faulty back-cooling fan to restore normal operation and prevent further electrical issues.
Technical Details
Repair Steps:
- Isolate Power: BEFORE any inspection or repair, disconnect the UNOX CHEFTOP or BAKERTOP MIND.Maps™ oven from its main power supply. Verify zero voltage at the terminal block with a multimeter.
- Access the Back-Cooling Fan: Carefully remove the rear access panel(s) of the oven to gain access to the control board compartment and the back-cooling fan. Note the position and routing of all wires and hoses.
- Identify the Fan: Locate the 230 V AC back-cooling fan, typically positioned near the control board to provide essential cooling.
- Perform Electrical Test: Disconnect the wiring from the back-cooling fan. Using a multimeter, check for continuity or a direct short across the fan’s power terminals. A reading close to zero ohms or an audible continuity beep indicates a short circuit. Also, check for continuity between the fan’s terminals and its metal casing, which would also indicate a short.
- Replace the Back-Cooling Fan: If a short is confirmed, carefully unmount the faulty back-cooling fan. Install a new, genuine UNOX replacement back-cooling fan (230 V AC) in its place, ensuring correct orientation and secure mounting.
- Reconnect Wiring: Reconnect the electrical wiring to the new back-cooling fan, ensuring all connections are tight and secure. Double-check that no wires are pinched or improperly routed.
- Reassemble and Test: Reinstall all removed panels. Restore power to the oven and initiate a control board reboot or start a cooking cycle to test if the circuit breaker still trips. Observe the new fan’s operation and listen for any unusual noises.
Common Questions:
Q: Why does a shorted back-cooling fan trip the circuit breaker?
A: A shorted back-cooling fan creates an abnormally low resistance path, drawing excessive current from the electrical supply. The circuit breaker is a safety device designed to detect this overcurrent and trip, interrupting the power flow to prevent overheating, damage to the electrical system, or fire hazards.
Q: What are the potential consequences of not replacing a shorted back-cooling fan promptly?
A: Operating the oven with a shorted back-cooling fan is extremely dangerous. It can lead to repeated circuit breaker trips, potential damage to the control board due to lack of cooling, severe electrical component failure, and a significant risk of electrical fire. Immediate replacement is crucial for safety and operational integrity.
Q: Can I repair the back-cooling fan, or must it be replaced?
A: Commercial kitchen equipment fans, especially those involved in critical cooling and designed for specific electrical loads, are typically sealed units and not serviceable. Attempting to repair a shorted fan is not recommended due to safety risks and potential for improper functionality. Replacement with a genuine UNOX part is the safest and most reliable solution.
When to call a technician
For this error, we recommend calling a certified technician. Do not continue operation or attempt repair yourself.
- Equipment shows a critical or stop-operation fault.
- You smell gas, burning, or see smoke or sparks.
- Error returns after following the steps above.
- You are not trained to work on this equipment.
- Warranty or safety could be affected by DIY repair.