f20
Moderate
Bosch · Washing Machines
Unexpected water heating
Quick Answer
Error code F20 on your Bosch Washing Machines means: Unexpected water heating. This is usually fixable — see the step-by-step guide below.
Affected Models
Applies to all models
Likely Causes
How to Fix It
1
Power off the washer immediately as this is a safety concern.
2
Replace the temperature sensor (NTC) and its relay.
3
If the sensor tests normal, replace the control board.
4
Do not use the washer until this issue is resolved.
Pro Tip
This fix requires some technical knowledge. If you're unsure about any step, consider contacting support or a qualified technician.
Parts You May Need
NTC temperature sensor
Heater relay
Control board
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