The E18 error on your Bosch Dishwasher means the machine has detected a water inlet fault, usually because water is taking too long to reach the correct level during the fill cycle. Check the water supply and inlet hose before assuming a major fault.
| Error code | E18 |
|---|---|
| Meaning | Long fill time / water inlet flow fault detected by the dishwasher's control board |
| Severity | Medium — the dishwasher will usually pause or stop the cycle until the issue is cleared |
| Time to fix | 15–45 minutes |
| Tools needed | Adjustable pliers, small bucket, torch |
What the E18 error means
Bosch dishwashers monitor how long it takes for water to reach the correct fill level during each wash cycle. If this takes longer than the internal limit, the control board raises the E18 code as a safety measure to stop the tub from underfilling or running dry. It's one of the more common Bosch dishwasher faults and is often linked to something blocking water flow rather than a faulty part.
In most cases the cause is mechanical — a kinked hose, closed tap, or clogged filter — rather than an electronic failure, so it's worth checking the simple things first before calling an engineer.
Common causes
- Water supply tap to the dishwasher is partially or fully closed
- Kinked, trapped, or crushed inlet hose behind the machine
- Blocked inlet filter or mesh screen where the hose connects to the dishwasher
- Low household water pressure affecting fill speed
- Faulty water inlet valve that isn't opening fully
- Air lock in the pipework after recent plumbing work
How to fix the E18 error
- Check the water tap: Make sure the tap feeding the dishwasher is fully open. A partially closed tap is one of the most common causes of this error.
- Inspect the inlet hose: Pull the dishwasher out carefully and check the hose isn't kinked, twisted, or trapped against the wall or cabinet.
- Clean the inlet filter: Disconnect the hose from the dishwasher and clean the small mesh filter where it connects. Debris here restricts flow and triggers the fault.
- Test water pressure: Run the kitchen tap on full to confirm normal household pressure. Very low pressure can prevent the dishwasher from filling within its time limit.
- Reset the dishwasher: Switch it off at the wall for two minutes, then restart the cycle to see if the error clears once flow is restored.
- Call an engineer if it persists: If water flow checks out fine and the error keeps returning, the water inlet valve itself may need replacing.
FAQ
Can I still use the dishwasher after an E18 error?
It's best not to until the cause is fixed, as the machine may not fill properly and dishes won't be washed correctly.
Does E18 mean the water inlet valve is broken?
Not always. Most cases are caused by a closed tap, kinked hose, or blocked filter rather than a faulty valve.
How do I reset my Bosch dishwasher after this error?
Turn it off at the wall socket, wait a couple of minutes, then switch it back on and restart the cycle.
