Error Code
low
Rational CM – Error E24: CombiMaster Error – Software Update Required
On your CombiMaster unit, error code E24 indicates that a software update…
Rational CM - Error CHnG: Change Polarity of Mains Supply
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 CombiMaster unit, the CHnG error code indicates an incorrect polarity of the mains power supply. This means the electrical wiring connection is faulty, posing a safety risk and preventing proper operation. This issue requires immediate attention from a qualified electrician or certified service technician.
Technical Details
Repair Steps:
- Safety First: Disconnect Power. Immediately disconnect the RATIONAL CombiMaster from the mains power supply at the main circuit breaker. Verify that power is completely off using a multimeter or voltage tester before proceeding with any inspection.
- Verify Mains Supply Polarity. This error typically arises from incorrect phase sequencing (for 3-phase units) or reversed neutral/line wiring. A qualified electrician should use appropriate testing equipment to check the polarity at the electrical outlet or the unit’s main terminal block according to local electrical codes.
- Inspect Wiring Connections. Carefully examine all visible wiring, especially at the main power input terminal block inside the CombiMaster and at the wall connection point. Look for loose connections, damaged insulation, or signs of charring/overheating that might indicate an improper connection.
- Consult Wiring Diagram. Refer to the RATIONAL CombiMaster’s electrical schematic diagram, which is usually found within the machine’s control panel or service manual. This diagram provides the precise wiring configuration required for safe and correct operation.
- Professional Intervention. Given the high voltage nature of this error, it is crucial that a licensed electrician or certified RATIONAL service technician performs the diagnosis and correction. Do NOT attempt to alter mains wiring if you are not qualified, as it poses a severe risk of electric shock and equipment damage.
- Test After Correction. Once the mains polarity has been professionally corrected and all connections are secured, restore power to the CombiMaster. Monitor the unit for normal startup and operation. If the CHnG error persists, further diagnostics by a qualified technician will be necessary to rule out other related electrical component failures.
Common Questions:
Q: What exactly does “change polarity of mains supply” (CHnG) mean on my CombiMaster?
A: The CHnG error on your RATIONAL CombiMaster indicates that the electrical wiring connecting the unit to your building’s main power supply has incorrect polarity. This could mean a reversed live and neutral wire, or an incorrect phase sequence in a 3-phase system, which prevents the unit from operating safely or correctly.
Q: Is it safe to continue using my RATIONAL CombiMaster with a CHnG error?
A: No, it is absolutely not safe. Operating the unit with incorrect mains polarity can lead to serious electrical hazards, damage to internal components, or even fire. You should immediately disconnect the power and arrange for professional service.
Q: Who should I call to fix the CHnG error on my CombiMaster?
A: You should contact a qualified and licensed electrician or a certified RATIONAL service technician. This error involves working with high voltage mains electricity, which requires specialized knowledge and tools to diagnose and correct safely.
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.