E12

Limescale Build-Up (Descale Required)

Description

Limescale has built up in the heat pump, usually in hard-water areas, reducing heating efficiency.

Appliance Error Codes Details

Error Code
E12
Error Name
Limescale Build-Up (Descale Required)
Appliance Type
dishwasher
Brand
Bosch
Severity
low

Additional Troubleshooting

1. Run a descaling cycle with a dishwasher descaler.
2. Refill the water-softener salt and set the correct hardness level.
3. Severe scale may need two or three descaling cycles.
4. Use rinse aid and salt regularly to prevent future build-up.

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Author: Pavel Volkov
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