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Bosch · error E18Bosch washing machine showing E18
An E18 code on a Bosch washing machine almost always points to a drainage problem — the machine started a cycle but couldn't pump the water out in the time it expected.
What it usually means
The control board runs a timer when it tells the pump to empty the drum. If the water level hasn't dropped enough by the time that timer runs out, it stops the cycle and shows E18 rather than risk flooding. The good news: the cause is usually mechanical and easy to reach, not electronic.
Common causes
- Blocked pump filter
The filter at the front-bottom of the machine catches coins, hair grips and lint. A clogged filter is the single most common cause — and a genuine 5-minute fix.
- Kinked or blocked drain hose
If the hose is pinched behind the machine or clogged, water can't leave fast enough.
- Blocked sink waste or standpipe
Where the hose feeds into a kitchen sink trap, a greasy blockage there will trigger E18.
- Faulty drain pump
The pump itself can fail or jam. This one needs a part — but it's an inexpensive, common one.
Most E18 faults are a cheap, fast fix — but you won't know whether it's a blocked filter or a failed pump until someone looks. That diagnosis shouldn't cost you a £100+ callout.
Note: exact fault behaviour varies by model and age — the only way to be sure is to have someone look. That's what the £29 call is for.
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