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Troubleshooting Common Combi Oven Issues

Troubleshooting Common Combi Oven Issues

Erin McGill |

When your combi oven acts up mid-service, it can throw your entire kitchen into chaos. While modern combi ovens are reliable workhorses, they still require regular maintenance, and occasionally, some hands-on troubleshooting.

Below, we break down the most common combi oven issues, why they happen, and how to fix them fast (or know when to call in the pros).

1. Oven Not Heating Properly

Symptoms:

  • Oven doesn't reach set temperature

  • Slow cooking times

  • Uneven results

Possible Causes:

  • Heating elements or steam generator failure

  • Door seal damage (heat escaping)

  • Temperature sensor fault

  • Limescale build-up affecting steam production

What to Try:
✅ Check the door gasket for cracks or warping
✅ Run a descaling cycle if you haven't recently
✅ Confirm the oven is correctly set to the desired cooking mode (steam, convection, combi)
❌ Don’t attempt to repair internal heating components unless qualified

2. No Steam or Weak Steam Output

Symptoms:

  • Food dries out during combi cooking

  • Steam mode ineffective

Possible Causes:

  • Water supply issue

  • Scale build up in boiler or injection system

  • Blocked or dirty steam inlets

  • Faulty solenoid valve

What to Try:
✅ Check water line and filters
✅ Run automatic descaling (if available)
✅ Clean or inspect the steam outlets
✅ Reset the oven to factory defaults if settings were changed

🛠️ Pro Tip: Poor water quality = more maintenance issues. Consider a water treatment system

3. Oven Won’t Start or Keeps Shutting Off

Symptoms:

  • No power

  • Random shut-offs

  • Display frozen or blank

Possible Causes:

  • Blown fuse or circuit breaker

  • Overheating protection activated

  • Electrical fault or moisture in controls

What to Try:
✅ Turn the oven off, wait 1–2 minutes, and restart
✅ Check for tripped breakers or loose plugs
✅ Let the unit cool fully before restarting
✅ If in a high-moisture environment, inspect for water ingress

⚠️ Persistent shutdowns = time to call for servicing.

4. Self-Cleaning Cycle Won’t Run Properly

Symptoms:

  • Cleaning doesn’t complete

  • Soap not dispensing

  • Error messages during cycle

Possible Causes:

  • Empty detergent tank

  • Clogged nozzles or drain

  • Sensor faults or blocked filters

What to Try:
✅ Refill detergent and rinse tanks
✅ Clean spray arms and filters manually
✅ Ensure the door seal is tight before starting
✅ Double-check that the correct cleaning program was selected

Strange Noises During Operation

Symptoms:

  • Whining, rattling, or banging sounds

  • Steam hissing excessively

Possible Causes:

  • Fan obstruction or worn bearings

  • Loose trays or racks

  • Excessive scale causing steam pressure fluctuations

What to Try:
✅ Make sure all internal racks and trays are seated properly
✅ Inspect fan area for blockages (after unplugging)
✅ Schedule a service to inspect mechanical parts if noise continues

Bonus: Common Error Codes and What They Mean

Error Code Meaning Action
E101 Temperature sensor fault Call service
E203 Water fill failure Check supply, filters
E305 Steam generator overheating Let oven cool, then restart
E901 Cleaning system error Check tanks, try reset

Refer to your oven's manual for model-specific codes (Rational, Unox, Lainox, etc.).

When to Call the Professionals

If you're experiencing:

  • Repeated error codes

  • Electrical faults

  • Internal steam leaks

  • Persistent heating problems

Don’t risk downtime, contact a certified Catercombi technician. We offer fast-response support, maintenance contracts, and same-day parts in many areas.

Final Tip: Prevent Problems Before They Start

Most combi oven issues are preventable with:

  • Daily cleaning

  • Weekly descaling (if required)

  • Routine service checks (every 6–12 months)

  • Proper water filtration

Need Support?
Call Catercombi for expert advice, servicing, or parts replacement. We keep your kitchen running, so you can focus on the food.

Call: 01227 913699  Email: service@catercombi.com Website: www.catercombi.com