Is water still sitting in the drum?
Drain it slowly through the lower filter area before opening the door or moving the machine.
Washer not draining
Bosch Washer E18 F18 Error? Check Filter and Hose First
A Bosch washer E18 or F18 error means drain water is not leaving fast enough. First manage standing water, clean the lower pump filter and cavity, then check the hose and standpipe.
The usual cause is a blocked drain path: a packed filter, a coin at the impeller, a kinked hose, or a restricted standpipe connection.
Good clue: debris in the filter or impeller pocket explains the code before a pump replacement.
Don’t start with: Do not order electronics or a drain pump first. Unplug the washer, drain the tub slowly, and prove the filter and hose path before buying parts.
Active clue: water is still in the drumDrain through the lower access area slowly, then clean the filter before running another cycle.
Active clue: pump hums but water barely movesLook for debris at the filter, impeller, hose end, or standpipe before replacing the pump.
Do this first
- Unplug the washer before opening the lower service area or removing a hose.
- Expect hot or dirty water at the filter. Let the load cool if the washer stopped during a hot cycle.
- Use towels and a shallow pan before loosening the filter cap; open it a little at a time.
- Stop if water is coming out faster than you can contain it.
- Stop if the outlet, cord, pump wiring, or lower cabinet area is wet.
- Call service if you smell burning, see scorch marks, hear harsh grinding, or the washer trips a breaker.
One-minute drain-path sort
Does the pump hum but water barely leaves?
Look for a blocked filter, a jammed impeller pocket, a kinked hose, or a plugged hose end.
Is there no pump sound during drain?
Clean the filter and hose path first. If they are clear, the pump, wiring, or control side needs closer diagnosis.
Does water back up at the standpipe or sink connection?
The house drain or siphon connection may be the restriction, not the washer.
Are the filter, impeller pocket, and hose all clear?
Now a model-matched drain pump is a fair parts candidate, especially if it is silent, seized, or weak.
Use the drain path before blaming the pump
The useful clues are low and wet: the filter cavity, the impeller pocket, the hose run, and the standpipe connection. A blocked path can make a good pump sound weak.
Before you buy anything
Copy the full Bosch model number from the washer label and prove the drain path first. A pump, filter cap, or hose should go in the cart only after the filter, impeller pocket, hose routing, and house drain connection point that way.
What E18 and F18 are telling you
Bosch treats E18 and F18 as drain-side faults. The washer expected water to leave, and the water did not move fast enough.
- The restriction is often close to the front lower pump filter or in the short drain path right after it.
- Listen during drain. A low hum with little water movement often means the pump is trying to run against debris.
- A silent drain attempt matters only after the filter and hose path are clear. A blocked path can hide what the pump is really doing.
- If the hose end or standpipe backs up, the washer may be fine and the drain connection may be the real choke point.
- A failed pump is possible, but it should come after the simple drain path proves clean.
- Good clue: water drains slowly or stops with debris in the pump filter or impeller pocket.
- Watch for a kinked hose or blocked standpipe after the filter is clean.
What not to do first
The bad move is replacing parts while water and lint are still sitting in the drain path. Start with the messier checks because they tell you the most.
- Do not keep restarting full cycles while the tub is holding water.
- Do not force the door while water is against the glass.
- Do not pry the filter cap with sharp tools or a long screwdriver.
- Do not order a control board for a drain-time code before the filter, impeller pocket, and hose are clean.
- Do not assume a humming pump is bad; it may be blocked by a coin, hair pin, elastic, or fabric scrap.
- Do not push the washer back until the drain hose has a gentle path with no sharp bend behind the cabinet.
- Do not order a drain pump while water and debris are still in the filter path.
- Do not put hands near wet wiring or open cabinet areas during cleanup.
Drain the tub without flooding the room
This is the slow part of the job. The washer can hold more water than the lower filter area looks ready for.
- Cancel the cycle, turn the washer off, and unplug it.
- Put towels and a shallow pan at the lower access door before touching the cap.
- If your model has a small drain tube, use it first and empty the pan as often as needed.
- If there is no tube, loosen the filter cap slightly, let water run into the pan, then tighten it again while you empty the pan.
- Once the flow slows down, remove the filter fully and keep the cap, seal, and threads where they will not pick up grit.
Clean the filter and impeller pocket
The filter is not clean until the cavity behind it is clean too. Small hard items can sit past the screen and stop the impeller.
- Pull lint, coins, buttons, hair pins, pet hair, and gray sludge from the filter screen and cap.
- Wipe the sealing face so the cap can tighten evenly without a slow drip later.
- Shine a flashlight into the pump cavity and look for string, elastic, or a hard object near the impeller.
- Turn the impeller gently with a fingertip or non-sharp tool. It should move in small steps, not feel locked solid.
- Stop if the impeller is broken, the cavity is cracked, or water has reached wiring below the pump area.
Check the hose and standpipe
A clean filter does not help if the discharge path is pinched or blocked. Watch the hose end, not just the pump sound.
- Pull the washer forward only far enough to see the drain hose without stretching supply lines or the power cord.
- Look for a crushed bend behind the washer, lint sludge at the hose end, or a hose shoved too far into the standpipe.
- If the hose is easy to remove and you can control the spill, flush it into a bucket to see whether water passes freely.
- Leave an air gap at the standpipe or sink connection. Do not seal the drain hose airtight into the pipe.
- If the standpipe or sink connection overflows during drain, stop washer troubleshooting and deal with the house drain.
| What you see | What it usually means | Next move |
|---|---|---|
| Filter packed with lint, coins, or small fabric | The washer could not move water through the pump inlet | Clean the filter, cavity, and cap threads, then run a drain-only cycle |
| Pump hums and the impeller is blocked | The pump may be good but jammed | Remove the debris, retest, and listen for a steady drain sound |
| Hose is kinked or hose end is packed with sludge | The discharge path is restricted after the pump | Straighten, clean, or replace the hose only if it stays damaged or blocked |
| Standpipe or sink connection backs up | The house drain cannot take the washer discharge | Stop and clear the plumbing side before blaming the washer |
| Path is clear but pump is silent, seized, or weak | Drain pump failure is now plausible | Match the pump by full model number before ordering |
When the pump actually earns attention
A drain pump is a reasonable repair only after the water has a clear route out of the washer. That keeps a simple blockage from turning into a wrong part.
- The pump moves up the list if the filter is clean, the impeller pocket is clear, the hose flows freely, and the washer still will not drain.
- No pump sound during drain can point to the pump or its wiring, but do not make that call while the filter is still packed.
- A rough grinding sound with no debris left in the cavity can mean the pump is damaged internally.
- If the pump runs for one load and fails on the next, write that down before service or parts shopping; intermittent faults are easy to misread.
- If a model-matched pump does not change the symptom, stop buying parts and schedule appliance diagnosis for wiring, sensing, or control faults.
Tools You May Need
These tools are for draining, seeing, and catching water. Skip any step that would put your hands near wet wiring or require major cabinet teardown.
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Shallow drain pan
Helps when: Use a shallow drain pan to control water while opening the Bosch lower pump filter slowly.
Skip it when: Skip filter work if you cannot manage standing water safely.
Compare shallow drain pans on Amazon
Inspection flashlight
Helps when: Use an inspection flashlight to find hair, trap sludge, code timing clues, or the first wet point without guessing.
Skip it when: Skip work until the area is dry, accessible, and safe to inspect.
Compare inspection flashlights on Amazon
Slip-joint pliers
Helps when: Use slip-joint pliers on accessible hose clamps only after the washer is unplugged and water is controlled.
Skip it when: Skip forcing clamps or hoses that require cabinet teardown or expose wet wiring.
Compare slip-joint pliers on AmazonReplacement Parts
Parts are later-stage decisions. Match every washer part to the full Bosch E-Nr or model number, not just to the E18 or F18 code.
Paid links. As an Amazon Associate I earn from qualifying purchases. Repair Riot may earn a commission at no extra cost to you.
Washer drain pump filter
Helps when: Use a washer drain pump filter cap only if the original is damaged, cracked, or will not seal after cleaning.
Skip it when: Skip replacing it before cleaning the filter cavity and checking for trapped debris.
Compare Bosch washer drain pump filters on Amazon
Washer drain hose
Helps when: Use a washer drain hose when the hose is kinked, blocked, split, or incorrectly routed after inspection.
Skip it when: Skip hose replacement if the blockage is in the filter cavity or standpipe.
Compare Bosch washer drain hoses on Amazon
Washer drain pump
Helps when: Use a washer drain pump only after the filter, impeller pocket, hose, and standpipe are clear and the pump still fails.
Skip it when: Skip pump replacement from E18 or F18 alone; match by Bosch E-Nr or full model.
Compare Bosch washer drain pumps on AmazonFAQ
What does E18 or F18 mean on a Bosch washer?
It usually means the washer is not draining water out fast enough. The most common causes are a clogged washer drain pump filter, debris in the pump, or a restricted washer drain hose.
Is E18 the same as F18?
For practical troubleshooting, yes. Both point you toward a drain problem first, so start with standing water, the filter, the pump cavity, and the drain hose.
Can I just reset the washer and keep using it?
You can try unplugging it for a few minutes, but if water is still in the drum or the code comes back, a reset will not fix the blockage or weak pump causing the problem.
Why does my washer hum but not drain?
That usually means the washer drain pump is trying to run but something is blocking the impeller or the pump is failing mechanically. Check the filter and pump cavity before replacing the pump.
Should I replace the pump right away?
Usually no. A clogged filter or hose is more common than a bad pump. Replace the washer drain pump only after you confirm the filter and hose are clear and the pump is still silent, seized, or too weak to move water.
Can a house drain problem cause this code?
Yes. If the standpipe or sink drain is backing up, the washer may not be able to discharge water properly. In that case the washer may be fine and the drain line needs attention.
Why does the code come back after I clean the filter?
Look one step past the filter. Debris can sit in the impeller pocket, the drain hose can be kinked behind the washer, or the standpipe connection can be restricted even after the filter looks clean.
How do I know if the Bosch washer drain pump is bad?
The pump is a better candidate after the filter, impeller pocket, hose, and house drain are clear. A silent pump, seized impeller, rough grinding, or very weak flow with a clear path points toward pump repair.
Can I run a spin cycle to force the water out?
Do not keep restarting spin or drain cycles while the tub is holding water. Drain the washer slowly through the lower access area first, then clean the filter and hose path before a controlled drain cycle.
Where do I find the model number before ordering parts?
Use the washer's rating label or Bosch manual lookup to get the full E-Nr or model number. Drain pumps, filter caps, and hoses can look similar but use different mounts, seals, and connectors.
Sources and reference notes
Repair Riot built this page around the visible drain path: standing water, filter debris, impeller movement, hose routing, and the point where a pump becomes a supported repair.
- Bosch washer error codes — official Bosch E18/F18 guidance for blocked or kinked drainage hose, pump cleaning, leak checks, and service escalation
- Bosch owner manual lookup — model-specific manual lookup and E-Nr rating-plate guidance before opening service areas or matching parts
- Bosch washing machine spare parts — manufacturer parts path for model-specific washer components