What to check yourself
Step 1. Empty the drain pump filter
This is the cause four times out of five. The filter sits behind a small hatch at the front bottom of the machine. Put a shallow tray and towels down first: a full drum empties about two gallons through that opening, and it comes out faster than most people expect. Unscrew the filter, pull out whatever is caught in it, and check the impeller behind it turns freely with a finger. Coins, hair grips, buttons and screws are the usual finds.
The water can still be hot if the cycle stopped mid-wash. Give it an hour to cool, or you risk a scald from a tray of water at 140F.
Step 2. Straighten the drain hose
Pull the machine out and look at the hose along its whole run. A kink behind the machine after it has been pushed back into place is the second most common cause, and it costs nothing to fix. The hose also must not sit lower than the machine along its run, or it siphons and confuses the pump.
Step 3. Check the standpipe or sink trap it drains into
If the filter is clean and the hose is straight, the blockage is downstream in the house plumbing, not in the machine. A standpipe clogged with lint backs water up into the machine. Detach the hose and pour a jug of water down the pipe: if it does not disappear immediately, the fault is the pipe.
What a technician will look at
Described so you know what you are paying for, not as steps to repeat.
Replace the pump
If the filter is clear, the hose is fine and the standpipe drains, the pump itself has failed, usually the motor winding rather than the impeller. On most Bosch models it is a front-access job that a competent owner can do, but it means tipping the machine and disconnecting a live circuit.
Unplug the machine at the wall before any work behind the front panel. Not the power switch, the plug.
When to call a technician
Call someone if the pump runs but no water moves, if it makes a loud buzz and stops, or if E18 comes back within a few cycles of a clean filter. Those point at the pump or the pressure sensor rather than a blockage, and both need the machine opened up.
What the repair costs
| Repair | Part only | Fitted by a technician |
|---|---|---|
| Clearing the filter or the drain hose | - | Free |
| Drain pump replacement | $20 to $100 | $150 to $400 |
A new machine of the same class runs $500 to $1,500. Once a quote passes about a third of that on an older appliance, the repair stops making sense.
Codes people confuse this with
Questions people ask
- How do I get the water out so I can open the door?
- Through the same filter hatch. Most Bosch models have a short grey drain tube tucked beside the filter: pull it out, hold it over a tray, and pull off its cap. It empties in stages, so you will need to re-cap it and empty the tray several times. Only then unscrew the filter itself.
- Is E18 the same as F18?
- Yes. Bosch uses E-codes on machines sold in North America and F-codes in Europe and the UK. The fault, the checks and the repair are identical.
- The filter was clean. What now?
- Work outward: the hose, then the standpipe, then the pump. A clean filter with a machine that still will not drain usually means the blockage is in the house plumbing rather than the appliance.
Which machines this applies to
Applies to
Bosch front loaders across Serie 2 to Serie 8, including the 300, 500 and 800 Series sold in North America. The same fault appears as E:36 -25 -26 and E:38 -25 -26 on machines that show sub-codes.
Last checked
2026-08-03