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 E18: B1 Cabinet Sensor Above 340°C (640°F)
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 E18 signifies that the B1 cabinet sensor has detected a temperature exceeding 340°C (640°F). This critical issue indicates a failed sensor, an actual oven overheat, or a wiring short. Immediate investigation is required to prevent damage or safety risks, as the machine will halt operation until resolved.
Technical Details
Repair Steps:
- Safety First: Disconnect the CombiMaster unit from the main power supply before performing any inspection or service to prevent electric shock.
- Allow Cooling: If the oven was recently in operation, allow it to cool down completely to a safe handling temperature.
- Inspect B1 Cabinet Sensor: Locate the B1 cabinet temperature sensor, usually positioned inside the cooking cabinet. Visually inspect the sensor and its wiring for any signs of damage, fraying, burns, dislodgement, or corrosion.
- Check Wiring & Connections: Trace the sensor’s wiring back to the control board. Check all connections for tightness and ensure there are no shorts or open circuits. Look for any pinched or melted wires.
- Test Sensor Resistance: Using a multimeter, measure the resistance of the B1 sensor. Compare the reading to the manufacturer’s specifications for NTC or PT1000 sensors (depending on the exact CombiMaster model). A reading significantly out of range indicates a faulty sensor.
- Examine Solid State Relay (SSR) (if applicable): If your CombiMaster model uses an SSR for heating element control, a stuck-closed SSR could cause continuous heating and lead to overtemperature. With power disconnected, check for continuity across the SSR’s output terminals; it should be open. If it shows continuity, the SSR is likely shorted and needs replacement.
- Inspect Heating Elements: Briefly check the heating elements for any visible damage or signs of constant activation (e.g., glowing hot when they shouldn’t be). A continuously energized element due to a control fault can cause overtemperature.
- Verify Control Board: If the sensor and SSR test fine, the issue might reside with the main control PCB. A faulty input circuit on the board could misinterpret sensor readings or fail to control heating elements properly. This requires advanced diagnostics or replacement by a qualified technician.
- Reset Error: After addressing the underlying cause, power cycle the unit to clear the error code. If the problem persists, further diagnostics are required.
Common Questions:
Q: What is the B1 cabinet sensor responsible for?
A: The B1 cabinet sensor is a critical safety and operational component that monitors the internal cooking temperature of your RATIONAL CombiMaster. It provides feedback to the control board to accurately regulate cooking processes and prevent overheating.
Q: Can I continue to use my CombiMaster if this error occurs?
A: No, it is highly recommended to immediately cease operation of the CombiMaster when error E18 appears. This error indicates a potentially dangerous overtemperature condition or a critical sensor malfunction that could lead to equipment damage or safety hazards.
Q: How can I prevent this error in the future?
A: Regular preventive maintenance is key. Ensure proper ventilation around the oven, routinely inspect wiring for wear and tear, and keep the cooking cabinet clean to prevent buildup that might impede sensor function or heating element efficiency. Promptly address any other operational anomalies.
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.