Rational iCombi Pro service level, calibration and gas errors
What the service level holds, the codes the self-test and calibration can give, the common gas burner errors, and the board LED codes.
What it is: Combi oven. Technician-level details for the iCombi Pro. For the Service numbers shown to users, see the iCombi Pro page.
Rational iCombi Pro service level, calibration and gas errors error codes
| Code | Meaning | Likely cause | What to do |
|---|---|---|---|
| (1|2) / (1|4) / (1|8) | Calibration: B1 / B2 / B4 sensor too hot | Oven not cool enough to start (all must be under 40 °C) | Let it cool. Codes can combine. |
| (2|1) / (2|2) | Calibration: differential pressure too low / too high | Pressure sensor P1 faulty or unplugged | Check P1. |
| (4|1), (10|1), (15|1) | Calibration value too small | Hose changed, water in the hose, or P1 faulty | Check the hose and P1. |
| (4|2), (10|2), (15|2) | Calibration value too large | As above | As above. |
| Timeout | A calibration step timed out | e.g. door open, heater or SSR fault | Fix and rerun. |
| Step 20 | Calibration finished successfully | ||
| 19 / 29 / 39 | Burner (upper hot air / steam / lower hot air) went out 5 times while running | Gas supply or flame sensing | Check gas and ignition. |
| 22 / 32 / 42 | Ignition failed 5 times | Gas, igniter or electrode | Check ignition. |
| 20 / 30 / 40 | Burner fan speed too far from set point | Fan or speed signal | Check the blower. |
| 110 | Scale-control pump fault while cleaner is in the steam generator | Pump | Check the pump. |
| 120 | Level electrode no signal while cleaner is in the steam generator | Electrode | Check the electrode. |
| 121 | Running without water | Water off | Fill the water. |
| I/O supply LED code 1–6 | Supply voltage / STM32 link / capacitive button / high-limit wiring / low-limit wiring / mains frequency not recognised | Board or wiring | Check the item named. |
How to enter service / parameter mode
- The service level is reached from Settings › Service; it asks for the technician password (from Rational, not shown here).
- Inside: basic settings and calibration, notification centre, and for each module (steam, convection, moisture, iCareSystem) diagnosis, module test, function test and service error history.
Other useful key presses
| Task | How |
|---|---|
| Self-test | Needed on new installs. Put a closed GN container 20 mm deep, open side down, in front of each fan wheel. Gas units need a flue gas check afterwards. |
| When to recalibrate | After replacing P1, the B4 sensor, a fan wheel, or the board and SD card together; after fitting hoods, new racks or a Combi-Duo; or if cooking is uneven. |
| Board replacement | Move the micro SD card to the new board; the unit restores its software backup, then update to the latest software. |
| eSTB reset | After fixing the cause, hold the eSTB reset button 3 s. |
For licensed technicians only. This equipment can involve mains voltage, high-voltage microwave circuits, gas and refrigerant. Isolate power (and gas) before opening panels, follow the manufacturer's manual and your local licensing rules (for example ARC refrigerant handling and electrical or gas licences). Wrong settings can spoil food or damage equipment. Check every value on the unit in front of you before changing it.
Based on: Rational iCombi Pro service reference sheet. Always check the manual for your exact model and software version.
ServiceModes is not affiliated with Rational or any other manufacturer. Written in our own words from the manufacturer's documentation.