Heating Fault — Water Not Reaching Temperature
The F14 error code means your Miele dishwasher's water is not heating to the temperature required by the selected program. The control board has detected that the target temperature was not reached within the allowed heating time.
~25%
DIY Fixable
$200-450
Typical Repair Cost
1-2 hrs
Pro Repair Time
Quick Assessment
Answer to continue safely
Is it safe to keep using?
Maybe. You can attempt one more cycle after a reset and descale. If F14 returns, stop — dishes will not be sanitized and detergent will not dissolve properly, leaving residue on everything.
Can I reset the code?
Yes. Yes. Turn off at mains for 5 minutes. If the code returns within 1–2 cycles, the heater or sensor has genuinely failed.
When to stop immediately?
Stop if you notice: F14 returns after a reset and descaling cycle, You notice any burning smell from the machine.
Symptoms You May Notice
Dishes come out cold and greasy
Without hot water, grease and detergent are not dissolved properly
Cycle runs much longer than normal
The machine extends the heating phase trying to reach the target temperature before timing out
Steam is absent when door opens
Normally you see steam after a hot cycle — its absence confirms the water was not heated
F14 appears at mid-cycle
The code typically triggers during the main wash or final rinse phase when heating is critical
Possible Causes
Failed Heating Element
The flow-through heater has burned out or developed an open circuit. This is the most common cause (~45% of cases).
Requires ProfessionalDefective NTC Temperature Sensor
The sensor that measures water temperature gives incorrect readings, making the control board think the water is cold even if the heater works.
Requires ProfessionalLimescale Buildup on Heater
Thick calcium deposits insulate the heating element, reducing its efficiency until it can no longer reach the target temperature.
DIY PossibleWiring or Connector Fault
A loose plug, corroded connector, or broken wire between the heater and control board interrupts the heating circuit.
Requires ProfessionalControl Board Relay Failure
The relay on the main PCB that switches power to the heater has failed. Less common but possible in older machines.
Requires ProfessionalSafe Checks You Can Do
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1
Power Reset
Turn off the dishwasher at the mains for 5 minutes. Restart and run a 65°C (Normal) cycle. Monitor whether the water heats by checking for steam when you crack the door after 20 minutes.
If the cycle completes without error, it was likely a one-time sensor glitch.
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2
Run a Descaling Cycle
Use Miele descaling tablets or a quality citric acid descaler. Run the hottest available program with an empty machine.
In hard-water areas, descale every 3–4 months to prevent heater coating.
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3
Check the Water Supply Temperature
If your dishwasher is connected to a hot water line, run the kitchen tap and verify hot water is actually reaching the machine. If the hot water supply is cold, the issue is your water heater — not the dishwasher.
Most Miele dishwashers are designed for cold-water connection and heat internally.
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4
Listen for the Heater
Start a cycle and listen carefully after the fill phase. You should hear a faint hum or ticking as the heater activates. Complete silence during the heating phase suggests a dead element or no power reaching it.
Place your hand on the outer door after 15 minutes — it should feel warm if the heater is working.
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5
Check for Related Codes
If F14 appears alongside F84 or F85, multiple heating-circuit components may be involved. Note all codes displayed — this information helps a technician diagnose faster.
Some models show codes in sequence — write them all down.
When to Call a Professional
Contact a qualified Miele technician if:
- The heater element shows visible damage or burn marks
- No heat at all after 20+ minutes of a wash cycle
- F14 appears together with F84 or F85
- The machine trips the breaker when the heating phase starts
- The appliance is under warranty — heater replacement should be covered
Need Professional Help?
Find qualified Miele technicians in your area for proper diagnostics and repair.
Schedule Appointment