Bosch dishwasher drain hose not draining — drain hose

Use only checks that match the exact appliance or system and its official guide.

1. Check 1

   With the dishwasher controls off and the floor dry enough to stand safely, record whether water is standing in the tub, whether the unit leaked underneath, whether a drain-pump sound was heard, and the exact displayed code if any.

   Expected result: Classify the result as no standing water, standing water with no code, E22, E23, E24, E25, E15, or an active leak or wet base area.

   Next step: If E15, an active leak, or water near an electrical outlet is present, stop and follow the safety boundary. Otherwise continue with the visible hose and connection inspection, keeping the code and symptom pattern for service if the check does not resolve it.

   Stop if: Do not run another cycle to test an active leak, wet base, burning smell, damaged cord, or water near electrical components.

   Why this matters

   Why: Standing water confirms that the drainage path or pump has not completed its job. E22 points toward the filter, E23 toward a drain-pump issue, E24 toward the drainage path, and E25 toward a blocked pump or pump-cover problem; E15 is a water-in-base safety condition rather than a routine hose-cleaning prompt.

2. Check 2

   From the cabinet or other ordinary safe access, trace the visible Bosch drain hose from the dishwasher connection to the sink siphon, air gap, or garbage-disposal inlet; do not pull the appliance out or disconnect a wet fitting.

   Expected result: Look for a sharp kink, crushed section, sag that can hold water, loose clamp or connection, hose rubbing on a cabinet edge, a blocked air-gap path, or a disposal connection that was recently changed.

   Next step: Photograph the route and connection, and restore only an obviously displaced external routing or secure connection when the model and plumbing instructions make that safe; otherwise leave it in place for a qualified appliance or plumbing technician.

   Stop if: Stop if the hose is split, hardened, leaking at the fitting, inaccessible without moving the appliance, or connected to a wet or damaged plumbing assembly.

   Why this matters

   Why: A visible kink, crush, or loose connection makes a hose or installation restriction more likely than an internal pump fault. A clean, open-looking route does not prove the hose is clear because an obstruction can be inside the hose or at the siphon connection.

3. Check 3

   Inspect the drain-hose termination at the sink siphon, air gap, or garbage disposal without dismantling the trap or forcing the hose; if a disposal was installed or replaced recently, verify from its installation documentation whether the dishwasher inlet knockout plug was removed.

   Expected result: Record whether the hose enters the intended inlet, the connection is open and secure, the air-gap or siphon path is visibly blocked, or the disposal port may still contain its knockout plug.

   Next step: Use the appliance and plumbing installation instructions or ask a qualified plumber to correct a connection or knockout-plug issue; do not drill into a connected disposal or open a trap full of wastewater as a trial repair.

   Stop if: Stop for wastewater leakage, an inaccessible disposal connection, a damaged trap, or any need to cut, drill, or replace plumbing without the correct installation instructions.

   Why this matters

   Why: A blocked siphon or air-gap path, a wrong or loose connection, or an intact disposal knockout plug can stop a Bosch dishwasher from draining even when the hose itself is not kinked. A normal-looking connection shifts attention back to the filter, pump cover, or internal pump.

4. Check 4

   Only with the dishwasher switched off and only as the exact Bosch owner manual permits, remove the filter and inspect the pump area; use a sponge to remove standing water and clear visible debris, and reinstall the filter and pump cover exactly as instructed.

   Expected result: Note food debris or glass-like sharp material, a blocked filter, a loose or missing pump cover, a clear pump area, or a cover that will not release or reseat without force.

   Next step: After safe reassembly, perform one controlled drain test if the manual allows and no leak or safety condition is present; if the area is inaccessible, damaged, or still blocked, arrange service instead of reaching deeper.

   Stop if: Do not reach blindly, handle sharp debris bare-handed, force the pump cover, use drain chemicals, or work on wiring or the pump motor.

   Why this matters

   Why: Bosch identifies filter and pump debris as common no-drain causes. A loose or missing pump cover fits Bosch's E25 guidance, while a clear and correctly reassembled area makes a hose, siphon, drain-pump, or other internal fault more likely.

5. Check 5

   With the hose connection, filter, and pump cover restored and no leak present, run only the model-approved drain or short test procedure and observe the outlet connection, water movement, unusual noise, and whether the code returns.

   Expected result: Record complete drainage with no leak, partial drainage or backflow, a returning E23/E24/E25, a new leak, or a pump that is silent or unusually noisy.

   Next step: Stop testing after one failed controlled check, save the code and photos, and request qualified appliance service; include the hose route, connection type, filter or pump observations, and any recent disposal or plumbing work.

   Stop if: Stop immediately for E15, any leak, water in the base, electrical or burning odor, loud grinding, or a test that requires moving the appliance or opening live electrical parts.

   Why this matters

   Why: A complete, leak-free drain after a permitted obstruction correction supports the hose or connection as the cause. Persistent water, backflow, a returning code, or abnormal pump behavior points to an internal drain-pump, wiring, installation, or plumbing fault that should not be guessed at.