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 E5: B3 Core Probe Sensor Defective
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, error code E5 indicates a defective B3 core probe sensor. This sensor is crucial for precise internal temperature monitoring during cooking. You will need to inspect the probe, its cable, and connection points for damage or corrosion. Replacement of the sensor is typically required to restore accurate temperature control and functionality.
Technical Details
Repair Steps:
- Safety First: Always disconnect the combi oven from the main power supply before performing any inspection or service to prevent electric shock.
- Inspect the Core Probe: Carefully examine the B3 core probe itself for any visible signs of damage, bending, corrosion, or insulation breaches. Ensure it is clean and free of food residue.
- Check Probe Cable and Connector: Trace the core probe cable from the probe handle back to its connection point, typically located on the control board or a dedicated sensor input board. Look for cuts, pinches, frayed wires, or loose/corroded connectors. Disconnect and re-seat the connector firmly.
- Verify Connection at Control Board: Locate the core probe input on the main control board. Ensure the wiring is correctly terminated and that there are no loose screws or corroded terminals.
- Test Probe Continuity (if possible): Using a multimeter, check the resistance across the core probe’s terminals. Refer to the RATIONAL service manual for expected resistance values at room temperature. A significantly open or short circuit reading confirms a faulty probe.
- Check for Water Ingress: Inspect the probe’s handle and cable entry points for any signs of water ingress, which can short circuit the internal wiring of the probe.
- Replace the Core Probe: If inspection or testing confirms the B3 core probe is defective, it must be replaced with a genuine RATIONAL spare part. Follow the manufacturer’s instructions for replacement, ensuring proper sealing and connection.
- Power On and Test: Reconnect power to the unit and restart the oven. Attempt to run a cooking program that utilizes the core probe to verify the error has cleared and the probe is reading correctly.
- Professional Assistance: If the error persists after replacing the probe, or if you are unsure about performing these steps, contact a certified RATIONAL service technician for further diagnostics, as the issue may lie with the control board or internal wiring.
Common Questions:
Q: Why is the core probe important for my CombiMaster?
A: The core probe is critical for precise cooking, especially when cooking proteins, as it measures the internal temperature of the food. This ensures food safety and optimal cooking results, preventing undercooking or overcooking.
Q: Can I still use my CombiMaster without a working core probe?
A: While the oven may operate in some manual modes (e.g., steam, convection with time-based cooking), any programs requiring core temperature monitoring will likely be disabled or produce unreliable results, compromising food safety and quality. It’s not recommended for precision cooking.
Q: Is this a common issue with RATIONAL CombiMaster units?
A: Core probes, like many external sensors exposed to high heat and moisture, can eventually wear out or sustain damage from repeated use, cleaning, or accidental impact. It is a known wear item that occasionally requires replacement.
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.