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 - Power Supply to Chemical Pump Not Enough - Cleaning Cycle Not Effective
Caution / Monitor Closely
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, insufficient power to the chemical pump indicates a problem with its electrical supply, leading to ineffective cleaning cycles. Begin by accurately measuring the AC voltage at the pump's power terminals with a multimeter. If the reading is outside the 120-140 V AC range, the power board likely needs replacement.
Technical Details
Repair Steps:
- Safety First: Disconnect the oven from the main power supply before performing any inspections or repairs. Always allow sufficient time for all components to cool down.
- Access the Chemical Pump: Locate and access the chemical pump. This typically involves opening service panels on the side or rear of the oven. Refer to your UNOX technical manual for exact component location and access procedures.
- Measure Power Supply at Pump:
- With the oven powered ON (temporarily and with extreme caution, observing all safety protocols), set your multimeter to V AC.
- Carefully measure the voltage applied to the chemical pump’s power terminals.
- The expected power supply range is 120 – 140 V AC.
- Evaluate Voltage Reading:
- If the voltage is NOT within 120 – 140 V AC: This indicates a problem upstream with the power delivery. The most likely culprit is the power board. Proceed to Step 5.
- If the voltage IS within 120 – 140 V AC: The power supply to the pump itself is sufficient, suggesting the issue lies with the chemical pump or its immediate connections. Proceed to Step 6.
- Replace the Power Board (If Voltage is Incorrect):
- Disconnect power to the oven again and ensure it is fully isolated.
- Locate and carefully remove the existing power board, meticulously noting all electrical connections and wiring routes.
- Install a new, genuine UNOX power board, ensuring all wiring is reconnected securely and correctly.
- Restore power and initiate a cleaning cycle to verify proper operation and adequate power supply to the pump.
- Inspect Chemical Pump and Connections (If Voltage is Correct):
- With power OFF, visually inspect the chemical pump for any physical signs of damage, leaks, or blockages in the intake or output lines.
- Thoroughly check all electrical connections to the pump for looseness, corrosion, or burnt wires. Clean or re-seat connections as necessary.
- Verify that the pump motor can rotate freely; sometimes calcification or debris can seize the impeller.
- Test Chemical Pump Functionality:
- If the pump appears physically sound and its electrical connections are good, the chemical pump itself may be faulty internally.
- Consider performing an electrical continuity test on the pump motor windings if accessible (with power off) or a functional test if your multimeter has the capability.
- If the pump shows signs of failure (e.g., no hum, no movement when power is applied, or incorrect electrical resistance), it will need to be replaced.
- Replace the Chemical Pump (If Faulty):
- Disconnect power to the oven.
- Disconnect the water and chemical lines from the chemical pump, being prepared for potential chemical residue or spills.
- Disconnect the electrical wiring to the pump.
- Remove the old pump and install a new, genuine UNOX chemical pump, ensuring proper orientation and mounting.
- Reconnect all fluid lines and electrical wiring securely.
- Perform a thorough leak check and test the unit by initiating a cleaning cycle to confirm the new pump’s operation.
Common Questions:
Q: Why is a proper power supply crucial for the chemical pump?
A: The chemical pump needs specific voltage and current to operate effectively, ensuring it delivers the correct amount of cleaning solution into the oven chamber. Insufficient power can lead to weak pumping, poor chemical dispersion, and ultimately, an ineffective cleaning cycle, compromising hygiene and machine longevity.
Q: How do I know if my power board is the problem or the pump itself?
A: The key diagnostic step is to measure the voltage at the pump’s terminals. If the voltage is outside the 120-140 V AC range, the power board is likely failing to supply adequate power. If the voltage is correct but the pump doesn’t run or performs poorly, the pump motor or internal components are probably at fault and require replacement.
Q: Can I ignore this issue if the oven still cooks?
A: No, you should not ignore this issue. An ineffective cleaning cycle will lead to a buildup of grease and food residue inside the oven, which can affect cooking performance, introduce odors, promote bacterial growth, and significantly shorten the lifespan of critical internal components like heating elements and fans. Timely repair is essential for hygiene and durability.
When to call a technician
Consider calling a certified technician if:
- The error keeps coming back after you've tried the steps above.
- You're not comfortable doing the checks or repairs yourself.
- You notice unusual noise, smell, or behaviour.
- Equipment is under warranty and you want official service.
- You need the unit back in service quickly with minimal downtime.