Rational combi oven error codes
What common iCombi, SelfCookingCenter and CombiMaster Plus service messages mean, safe checks to try first, and when to call a technician.
Error on the display and service starting soon? Call 0800 90 60 30. Calls are answered 24 hours, 7 days. Technician cover runs 7 days, with after-hours emergency cover. We aim to respond to emergencies within 2 hours, depending on workload. This is a target, not a guarantee.
CES Wellington is Rational trained and approved. This page covers common operator messages on iCombi Pro and iCombi Classic, and on SelfCookingCenter and CombiMaster Plus. It does not cover iVario. Codes differ between those families, so use the section that matches your machine. Photograph the display and note the model from the rating plate before you switch off. See Rational combi oven service and all brand pages on error codes.
The lists below are the common messages an operator sees — water supply, cleaning, door and probe issues, fans, the steam generator and temperature sensors. They are not a full service-code catalogue. If your code is not listed, photograph the display and call us.
iCombi Pro and iCombi Classic
Only one service message is shown in the foreground on iCombi. The training manual says you can swipe vertically on that message to see if others are behind it.
| Code | What it means | What you can safely do |
|---|---|---|
| Service 10 | SC pump / pump-off path: the machine is not pumping water away as expected (SC pump, combi water box or pump-off hose). | The unit can often still be used for cooking. Call us. Leave the panels on. |
| Service 11 / 12 / 13 | Water filling or flow sensing problem (level electrode or CDS water-flow sensor). | Check the water tap is fully open. If it comes back, call us. Leave the panels on. |
| Service 20.x | A temperature sensor (thermocouple) has failed. Sub-codes identify the cooking cabinet, control, humidity or steam generator sensors. | Call a technician. Leave the panels on. |
| Service 23 / 24 | Steam heating or hot-air heating fault (SSR). | Call a technician. Leave the panels on. If it is safe, switch off at the wall or isolator. |
| Service 25 | No water flow detected when it should hit the fan during cleaning. Check the water supply, pressure, hoses and that racks or a trolley are in the correct position. | Open the water tap fully and check nothing is blocking the cabinet as the manufacturer directs for cleaning. If it comes back, call us. |
| Service 26 / 27 | Drain or ball valve has not reached the open or closed position (including XS ball-valve messages). | Call us. Leave the panels on. If a cleaning programme is running, do not leave cleaner in the cabinet — call us for advice. |
| Service 28.x | A thermal element is out of range — for example the steam generator is too hot, or the cooking cabinet is too hot or too cold. | Call a technician. Leave the panels on. If it is safe, switch off at the wall or isolator. |
| Service 29 | The control-board temperature is too high. | Check the air filter under or around the control panel is not blocked, and that the unit is not sitting in an external heat source. If the message remains, call us. |
| Service 30 | Moisture or climate control fault. | The unit may still cook with limitations. Call us. |
| Service 31.x | Core temperature probe fault (cabinet probe or a connected USB core probe). | You can usually still cook without using the core probe. Call us to have the probe checked. |
| Service 32.x / 33.x | Gas or combustion-system fault (gas units only), including failed ignition or repeated unsuccessful resets. | Close the gas valve. Leave the panels on. Call us. |
| Service 34.xx | A bus signal is missing from a component such as a fan motor, pump board or ignition box. | Call a technician. Leave the panels on. |
| Service 55 / 56 / 57 | A fan motor (top, bottom or middle) has not reached its set speed. Heating is blocked. | Call a technician. Leave the panels on. |
| Service 72 | The electronic safety temperature limiter (eSTL / eSTB) for hot air or steam has tripped. A service call is needed. | Call a technician. Leave the panels on. If it is safe, switch off at the wall or isolator. |
| Service 130 | Manual descaling is necessary (the filling volume is below 80% of the reference volume). | The steam generator needs descaling. Call us to arrange this. Do not open the panels or pour descaler unless you have been trained to use the unit’s own programme. |
Source: RATIONAL Service Reference iCombi, 80.51.872, V05, November 2022 (English); RATIONAL iCombi Pro / iCombi Classic Training Manual, 80.51.271, en-GB v04 (displayed messages, including Service 72); and the 80.51.321 troubleshooting / error-table guides (ET V04 and TM V03). Meanings are the operator-facing titles and conditions from those documents, not the technician repair steps.
SelfCookingCenter and CombiMaster Plus
On a SelfCookingCenter, faults that still allow cooking can often be suppressed with the Back button. The operating manual still says to notify customer service. CleanJet+care messages have extra rinse steps if cleaner is in the cabinet.
| Code | What it means | What you can safely do |
|---|---|---|
| Service 10 | Water is not pumped away during the steam-generator automatic drain (SC-Automatic). | On a SelfCookingCenter it can often be cleared with the Arrow button and the unit can still cook. Please call us. |
| Service 11 / 12 / 14 | Water filling or level-sensing problem. Service 14: the unit can only be used in Dry Heat until it is repaired. | Check the water tap is open. Call us. Leave the panels on. |
| Service 20 | A cooking-cabinet or related temperature sensor (thermocouple) is defective. | SelfCooking Control modes and programmes may not work; some Combi-Steamer use may still be possible. Call us. |
| Service 23 / 24 | Steam or hot-air heating fault. Displayed continuously. | Switch the unit off and call us. |
| Service 25 | No water flow detected during CleanJet+care cleaning. | Open the water tap fully, check the incoming screen, and remove containers from the cooking cabinet. If Service 25 occurs during cleaning, remove any cleaner tabs and rinse the cabinet thoroughly with the hand shower, including behind the air baffle. The unit can be used for cooking temporarily. Call us. |
| Service 26 / 27 | Drain valve has not found the open or closed position. CleanJet+care may not be possible. | If this appears during CleanJet+care, use Interrupt CleanJet as the operating manual describes, then remove tabs and rinse the cabinet if the message remains. For Service 27, the operating manual says to switch the power off at the mains for 5 seconds and on again. Call us if it remains. |
| Service 28 | Steam generator temperature is too high (the service manual describes the steam-generator sensor going above 180°C). | Call us. The steam generator may need descaling. Leave the panels on. |
| Service 29 | Control-panel electronics are too hot (above 85°C in the service manual). | Check the air filter under the control panel, and clean or replace it if needed. Check whether an external heat source is affecting the unit. If the message persists, call us. |
| Service 30 | Moisture or humidity control is not working. | The unit can be used for cooking with limitations. Call us. |
| Service 31 | Core temperature probe is defective. | The unit can be used for cooking without the core temperature probe. Call us. |
| Service 32 / 33 (gas units) | Gas ignition or combustion fault. Service 33 is displayed continuously after being reset four times. | Close the gas valve. Call us. |
| Service 34 | A bus (internal communication) signal is missing. | Call a technician. Leave the panels on. |
| Flashing water-valve symbol | Low water: the water valve may be closed, or the water intake filter on the unit may be clogged. | Open the water valve. If you are confident doing so, close the water valve, unscrew the water intake, remove and clean the intake filter, then refit it and check for leaks, as the operating manual describes. Call us if it remains. |
| Change polarity (gas units) | The power supply is not connected with the correct polarity. | Call us. Do not start swapping electrical connections yourself. |
| Reset (gas units) | The gas supply to the unit may be interrupted, or the gas pressure may be too low. | Open the gas valve if it is closed, and switch on any required ventilation. If Reset stays on the display, call us. |
Source: SelfCooking Center operating instructions, Fault messages chapter; and RATIONAL Training Manual 80.51.130, V08 en, SCC/CMP, September 2018 (service error-message definitions). “Before you call customer service” checks such as the flashing water-valve symbol are from the same operating instructions.
CombiMaster Plus display codes
CombiMaster Plus units in this family can also show short codes on the cabinet and time displays.
| Code | What it means | What you can safely do |
|---|---|---|
| H20 / OPEn | No water supply to the steam generator (cabinet display H20, time display OPEn). | Open the water tap. If it comes back, call us. |
| CHnG / PoL | Gas units: wrong polarity of the mains supply. | Call us. Do not start swapping electrical connections yourself. |
| E3 | Cooking-cabinet temperature sensor (B1) defective. | Call a technician. Leave the panels on. |
| E4 | Quenching / control temperature sensor (B2) defective. | Call a technician. Leave the panels on. |
| E5 | Core probe sensor (B3) defective. | You can usually still cook without the core probe. Call us. |
| E6 | Steam generator temperature sensor (B5) defective. | Call a technician. Leave the panels on. |
| E7 | Temperature sensor on the control board defective. | Call a technician. Leave the panels on. |
| E1 | External memory (EEPROM) data error. | Call a technician. Leave the panels on. |
| E2 | Heating blocked by an energy-optimising system. | If your site uses energy optimisation, wait and try again. If it remains, call us. |
Source: RATIONAL “SCC Service Reference” / “CM Service Reference” (Rational service codes, edition 01-2006); and 80.51.130, V08 en, September 2018, CM_P error messages. The scanned table in 80.51.130 does not always show every display string clearly in the text layer, so only codes also named in the service-reference sheet are listed here.
Safe checks to try first
- Water supply: the water tap or valve to the oven is fully open.
- Door: closed correctly (on floor units the door handle points down when it is shut, according to the SelfCookingCenter operating instructions).
- Cleaning programmes: no trays or containers left in the cabinet; racks or trolleys in the correct position.
- Air filter: the air filter at the control panel is not blocked (for board-temperature messages).
- Gas units: the gas valve is open for normal use; if a gas fault is showing, close the gas valve and call us.
Leave the panels on. There are live electrical parts inside. If you see water near electrics or smell burning, switch off at the wall or isolator if it is safe to do so, and call us.
When to call a technician
- The message stays after the safe checks above.
- The code is a temperature-sensor, heating, fan, bus, safety-limiter or gas fault.
- A cleaning programme has aborted and cleaner may still be in the cabinet.
For day-to-day care your team can do, see how to maintain a Rational combi oven and combi oven repairs.
FAQ
What does Service 25 mean on a Rational combi?
Service 25 means no water flow was detected during cleaning. Open the water tap fully, check the incoming screen, and take containers out of the cabinet. If it happens during CleanJet+care, remove tabs and rinse the cabinet, including behind the air baffle. Then call 0800 90 60 30.
What does Service 31 mean on a Rational combi?
Service 31 means the core temperature probe is faulty. You can usually still cook without the probe. Call us to have it checked.
What does Service 32 or 33 mean on a gas Rational?
These are gas or combustion faults. Close the gas valve and call 0800 90 60 30. Leave the panels on.
Are iCombi codes the same as SelfCookingCenter codes?
They are related, but not always identical, and CombiMaster Plus uses a different E / H20 style display. Use the section that matches your machine and send us a photo of the display.
My Rational shows Service 72. What should I do?
On iCombi Pro and Classic, Service 72 means the electronic safety temperature limiter has tripped. A service call is needed. Switch off if it is safe, leave the panels on, and call 0800 90 60 30.
Do you cover Rational iVario on this page?
No. This page covers iCombi Pro and Classic, SelfCookingCenter and CombiMaster Plus. We do not have an iVario error-code manual in this set. Call 0800 90 60 30 with a photo of the display and we will help from there.
Error still showing?
Call 0800 90 60 30 or book a job. The line is answered 24 hours, 7 days. Extra or out-of-hours charges may apply.