NTC Heater Sensor Short Circuit
The F1 error code on your Miele Oven indicates ntc heater sensor short circuit. This is a High severity issue. The NTC temperature sensor for the oven heater has a short circuit. Found on older Miele H-series ovens (H394B era and similar Novotronic models). The oven cannot regulate temperature safely and will not operate. What […]
~10%
DIY Fixable
From $150
Typical Repair Cost
1–2 hrs
Pro Repair Time
Quick Assessment
Answer to continue safely
Is it safe to keep using?
No. Without a functioning temperature sensor, the oven cannot regulate heat. Using it risks overheating or underheating food unsafely.
Can I reset the code?
Yes. Power cycling may clear a moisture-related F1. If the NTC sensor has physically failed, the code will return.
When to stop immediately?
Stop if you notice: F1 returns after power cycling and drying, The sensor or its wiring is visibly damaged.
Symptoms You May Notice
"F1" on the oven display
Appears immediately when the oven is turned on or during heating.
Oven will not heat
The heating cycle does not start or stops immediately.
Oven shuts off mid-cycle
May heat briefly then cut out when the sensor reading becomes erratic.
Possible Causes
NTC sensor short circuit
The NTC thermistor inside the oven cavity has failed with a short circuit, reporting near-zero resistance.
Requires ProfessionalDamaged sensor wiring
The wire connecting the NTC sensor to the control board is damaged, melted, or pinched — creating a short.
Requires ProfessionalMoisture on sensor connections
Steam cleaning or heavy moisture use has caused a temporary short on the sensor connector.
DIY PossibleSafe Checks You Can Do
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1
Power cycle the oven
Turn off the oven at the circuit breaker for 5 minutes, then turn it back on.
If F1 was caused by temporary moisture, drying out may resolve it.
-
2
Let the oven dry
If you recently used steam cleaning or a steam oven function, leave the oven door open for several hours to dry completely.
Moisture on the NTC connector is a common cause of temporary F1.
-
3
Check for visible damage
Look inside the oven cavity for a thin metal probe (the NTC sensor, usually at the top or back). Check if its wire is visibly damaged.
Do not touch or pull on the sensor — just visual inspection.
When to Call a Professional
Contact a qualified Miele technician if:
- NTC sensor reads near-zero ohms (short circuit confirmed)
- Sensor wiring melted or charred
- Control board problem
Need Professional Help?
Find qualified Miele technicians in your area for proper diagnostics and repair.
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