Bosch Washer Error Code E18

Bosch Washer Error Code E18 – What It Means and Why It Happens

The Bosch washer error code E18 is a drain-related fault that indicates the machine cannot pump water out properly. This error is commonly triggered when the drain pump is blocked, the drain hose is kinked or clogged, the debris filter is obstructed, or the pump impeller is damaged. When E18 appears it may interrupt the wash cycle, leave clothes soaking wet, cause longer cycle times, and in rare cases lead to water leaks or overflow if the washer cannot remove water as expected. Left unresolved, a continued inability to drain can increase wear on the pump motor, create unpleasant odors from standing water, and in severe cases create a slip or electrical hazard if water escapes the cabinet.

Common Causes

• Clogged debris filter or pump trap with coins, lint, hair, or small garments
• Kinked, crushed, or clogged drain hose
• Obstruction in household drain or standpipe causing poor outflow
• Damaged or failed drain pump motor or worn pump impeller
• Foreign objects lodged in the pump inlet or sump area
• Incorrect installation height or routing of drain hose causing siphoning
• Faulty control board or faulty pump relay (less common)

Troubleshooting Steps

1. Stop the machine and unplug it from the power supply to ensure safety before any inspection or repair.
2. Locate and open the service flap at the base front of the washer. Place a shallow pan and towels to catch residual water.
3. Slowly open the small drain cap to release water into the pan. This prevents spills when removing the debris filter.
4. Remove and inspect the debris filter for lint, coins, hair pins, or small garments. Clean thoroughly and reinsert securely.
5. Visually inspect the pump inlet and sump for visible foreign objects. Remove any debris using pliers or gloved hands.
6. Check the drain hose for kinks, bends, or visible blockages. Detach and run water through the hose to confirm flow.
7. Confirm the drain hose is installed at the correct height and not inserted too far into the standpipe, which can create a siphon and cause draining issues.
8. With the washer unplugged, try to turn the pump impeller manually (if accessible) to check for seizing. If it does not spin, the pump may need replacement.
9. Reconnect power and run a short drain/spin cycle after cleaning. If E18 clears, monitor several cycles to ensure reliability.
10. If the error returns, test the pump by running a diagnostic mode (refer to your modelâs service sheet) or listen for the pump motor running during drain. No motor sound suggests a failed pump or electrical fault.
11. Inspect wiring connections to the pump for loose or corroded connectors. Repair or replace damaged connectors as needed.
12. As a last step, if mechanical and simple electrical checks fail, have a qualified technician test the pump current draw and the control board pump relay to determine if a pump or board replacement is required.

Maintenance and Prevention Tips

• Clean the debris filter monthly to prevent lint and objects from reaching the pump.
• Check pockets and remove coins, keys, and small items before washing clothes.
• Use a mesh laundry bag for small items like socks and baby clothes.
• Inspect the drain hose periodically for kinks or damage and replace if brittle.
• Avoid overloading the washer which can strain the pump and trap debris in the filter.
• Run a maintenance wash with hot water and a washing machine cleaner monthly to reduce buildup.
• Make sure the drain hose is installed to the recommended height and not inserted too far into the standpipe.
• Keep the area under the front service flap clear so you can access the filter quickly.
• Use recommended detergent amounts to reduce residue that can clog filters.
• Inspect and clean the pump impeller area during annual maintenance if accessible.
• Install a mesh trap or screen in the household drain to prevent larger objects from entering the home plumbing.
• Balance loads to avoid excessive vibration that could damage hoses and connectors.
• Replace old or cracked drain hoses every 5-7 years or when you see wear.
• If you have pets, check pockets and fabrics for pet hair that can accumulate in the filter.
• Keep the washer door slightly open between uses to help dry the interior and reduce odor-causing residue.
• Consider a professional check-up at regular service intervals, especially for high-use households.

Frequently Asked Questions

Q: Can I keep using the washer when E18 appears?

A: It is not recommended to continue normal use. E18 means water is not draining properly and continued operation can leave clothing wet and risk leaks. Stop the cycle, unplug the machine, and perform the basic checks listed above.

Q: How much does it cost to replace a Bosch drain pump?

A: Costs vary by model and region but typically range from a modest parts fee plus labor. Expect a parts cost in the lower to mid range and technician labor depending on local rates. Get an estimate from an authorized Bosch service center.

Q: I cleaned the filter but the code returned. What now?

A: If cleaning the filter doesnât fix it, check the pump impeller for damage, ensure the drain hose and household drain are clear, and verify pump electrical connections. If the pump motor does not run during drain cycles, the pump or control board may need replacement.

Q: Is E18 covered under warranty?

A: If your appliance is still under Bosch warranty, drainage faults caused by defective parts may be covered. Damage from foreign objects or improper installation is often not covered. Check your warranty terms and contact Bosch support or your retailer.

Conclusion and Safety Notice

Diagnosing an E18 error is often straightforward and can be resolved by cleaning the debris filter and checking the drain hose, but always prioritize safety. Disconnect power before opening the service panel or working on internal parts. If you are uncomfortable performing these steps, if water is leaking, or if electrical faults are suspected, stop and contact a qualified appliance technician. Attempting complex electrical repairs without proper training can be dangerous.

When in doubt, call a Bosch authorized service provider. Professional technicians can test the pump, inspect electrical controls, and replace parts safely to get your washer back to reliable operation. Proper maintenance and prompt attention to E18 will keep your Bosch washer draining efficiently and extend its service life.