Bosch Washer Error Code F18: Meaning and Fix
Reading the washer display
On a washer the code appears on the digital display or as a pattern of flashing cycle lights. Note it exactly, including any dashes or sub-codes, then unplug the washer for five minutes and run a short drain cycle to see whether it returns. Bosch shows the code with a leading E and a number on both dishwashers and washers.
Bosch (part of BSH Home Appliances) uses E-numbered codes on dishwashers and washers. Its dishwashers share control platforms with Thermador and Gaggenau, so the same fault can appear on those brands. The codes apply to model numbers such as SHPM65Z55N, SHE53T55UC and WAT28400UC; check the label on your unit to confirm yours.
What causes F18
- Food scraps, lint, coins or other debris blocking the drain pump, filter or hose
- A kinked, crushed or clogged drain hose or standpipe, or a disposal knockout plug that was never removed
- A weak, jammed or burned-out drain pump motor
- Standpipe or washer box clogged with lint
How to fix it
- Stop the cycle, switch the appliance off and unplug it (or flip its breaker) before touching anything.
- Bail out standing water with a cup and towel, then clean the filter or pump cover and remove anything that does not belong.
- Pour water down the standpipe to check it drains fast.
- Check the drain hose from the machine to the sink or standpipe for kinks, crush points and clogs; straighten or flush it with warm water.
- Look for a disposal knockout plug or a drain loop that sits too low, which can siphon or block flow.
- Restore power and run a short drain or rinse cycle; if the pump hums but does not move water, replace the drain pump.
Parts you may need
| Part | Part no. | Buy |
|---|---|---|
| Washer Drain Pump | 00144486 | Find part |
Part numbers are OEM references; confirm fit by your model number before ordering. Some links are affiliate links; we may earn a commission at no extra cost to you.
Questions
What does error F18 mean on a Bosch washer?
Emptying the tub took too long. Exact behavior can vary by model and software version; confirm against your own manual.
Can I keep using my washer while F18 is showing?
Not really. Water that stays in the machine smells, breeds bacteria and keeps the code coming back, so clear the drain path first.
How do I clear F18, and can I fix it myself?
Cancel the program, switch the appliance off and leave it unplugged (or the breaker off) for about five minutes, then restart. The code only stays cleared if the underlying problem is fixed, so work through the steps above. This one is usually a do-it-yourself job with basic tools.
Other Bosch washer codes
Sources
Part numbers are OEM references; confirm fit by your model number before ordering. Meanings compiled from manufacturer and parts-retailer documentation; see sources below. Unplug the appliance before opening it.
Applies to models including WAT28400UC, WAT28402UC, WAW285H1UC, WAP24200UC.