Dishwasher
E18
The E18 error code on an AEG dishwasher signals a water supply problem — specifically, the machine isn’t filling with water fast enough or at all. It’s a common fault, and in many cases you can fix it yourself without calling an engineer.
What does this error mean?
E18 means the dishwasher’s control board has detected that the appliance failed to reach the required water level within the expected time. The machine monitors fill time closely, and if water isn’t arriving quickly enough, it shuts down to protect the pump and heating element. This is a flow or supply issue, not a software glitch.
Est. repair cost
£80–£140 professional repair; £20–£50 DIY part (inlet solenoid valve) plus £0 if it’s just the filter or hose
🔍 Likely causes
🛠️ Step-by-step fix
Turn off the dishwasher and switch off the water supply tap (usually under the sink). Pull the machine forward slightly to access the back.
Check the inlet hose for kinks or sharp bends. Straighten it fully and make sure it isn’t pinched against the wall or cabinetry.
Unscrew the inlet hose from the back of the dishwasher. Inside the connection port, you’ll find a small mesh filter screen. Remove it carefully, rinse it under the tap to clear limescale or debris, and refit it.
Ensure the water supply tap under the sink is fully open — turn it anticlockwise as far as it goes.
Reconnect the hose, turn the water back on, and run a short wash cycle to see if E18 clears. If it does, the job is done.
If E18 returns after all the above, the water inlet solenoid valve itself is likely faulty and needs replacing — this is a straightforward part swap, but if you’re not confident working with the machine’s wiring connections, call a professional at this stage.
📞 When to call a professional
If cleaning the filter and checking the hose doesn’t resolve E18, the inlet solenoid valve has probably failed and needs replacing. Tell the engineer you’re getting an E18 fault and that you’ve already checked the hose and filter — this saves diagnostic time. You should also call out if you notice any water leaks from the inlet connection after reassembly.
⚖️ Repair or replace?
An inlet solenoid valve for an AEG dishwasher typically costs £20–£50 for the part; a professional repair including labour will run £80–£140. If your dishwasher is under 7 years old, repair is almost always worth it. Over 10 years old with other issues brewing, a replacement dishwasher — entry-level models start around £300 — may be the smarter long-term spend.