3-second answer: Standing water in the bottom of a Bosch dishwasher almost always means something is blocking the drain path. Nine times out of ten it’s a clogged filter or a kinked/blocked drain hose. Other culprits are the drain pump, a stuck check valve, the air gap or garbage-disposal knockout plug, or a control fault flagged by an E24/E25 error. Most causes are homeowner-fixable in under 30 minutes — here’s how to clear them in order.
First: is it really a drain problem?
A small amount of clean water sitting in the cylinder around the filter is normal on a Bosch — it keeps the seals from drying out. You have a real drain problem when there’s standing dirty water across the tub floor at the end of a cycle, dishes come out wet and gritty, or the cycle stops partway with water still inside. If that’s what you’re seeing, work through the causes below in order — they’re listed most-common first.
6 reasons a Bosch dishwasher won’t drain
- Clogged filter. The cylindrical filter at the bottom traps food and grease. Bosch recommends cleaning it monthly; a blocked filter is the single most common drain failure.
- Kinked or clogged drain hose. The hose runs from the pump to your sink drain or disposal. It can kink behind the unit or clog with grease and debris.
- Blocked garbage-disposal knockout or air gap. If your drain hose connects to a new garbage disposal, the internal knockout plug may never have been removed — a classic install-day cause. A clogged sink air gap does the same thing.
- Failed or jammed drain pump. Glass shards, a twist-tie, or a fruit pit can jam the impeller; the pump motor can also simply wear out.
- Stuck check valve. The valve that stops drained water flowing back can stick shut with debris.
- Control or electronic fault. Less common, but a drainage error such as E24/E25 can point to the pump circuit or control board.
No time to troubleshoot, or water won’t clear? Call (647) 834-4646 for same-day Bosch dishwasher repair across the GTA — flat $89 service call applied to the repair.
What Bosch E24 and E25 mean
If your Bosch is flashing an error, it’s telling you where to look:
- E24 — drainage fault: water isn’t leaving fast enough. Usually a clogged filter, blocked hose, or air-gap/knockout issue. Start with the 5-step fix below.
- E25 — drain-pump problem: the pump cover is loose or the pump is blocked/jammed. Check the pump area specifically.
These pair closely with our deep dive on the Bosch dishwasher E24 error code if you want the full code walkthrough.
The 5-step fix (about 30 minutes)
Have towels and a shallow bowl ready — there will be water.
- Scoop the standing water. Bail out the tub with a cup and sponge so you can work dry.
- Clean the filter. Twist out the cylindrical filter assembly at the bottom, rinse it under the tap, and clear the well underneath. Reinstall snugly.
- Check the drain hose. Pull the dishwasher out, straighten any kinks, and detach the hose end at the sink/disposal to check for grease clogs. Flush it through.
- Clear the disposal knockout / air gap. If recently connected to a disposal, confirm the knockout plug was removed. Clean the air gap on the countertop if you have one.
- Run a short rinse cycle. If the water drains away cleanly, you’ve fixed it. If it still pools, the drain pump or check valve is the likely culprit — see below.
When it’s the drain pump or check valve
If cleaning the filter and hose didn’t help, the drain pump is the next suspect. With the dishwasher unplugged, the pump can be accessed at the base of the tub; debris jamming the impeller is sometimes visible and removable. A pump that hums but won’t move water, or is silent entirely, usually needs replacement. This is where many homeowners hand it off — it involves disconnecting power and water and partially tipping the unit, and on Bosch models the lower assembly is tightly packed. A technician can confirm the pump versus the control board quickly and carry the right part.
When to call a pro
Call a technician if:
- The filter, hose, and air gap are clear but water still won’t drain.
- An E24/E25 returns after cleaning.
- The drain pump is silent, humming, or grinding.
- Water is leaking onto the floor as well as failing to drain.
Appliance Forever’s technicians are factory-trained on Bosch and every major brand. We diagnose the drain pump, check valve, and control board, confirm the fix, and give you an upfront quote first — a flat $89 service call applied to the repair, with same-day service on most calls. See our dishwasher repair page for everything we cover, or our guide on dishwasher noises if you also hear grinding.
Frequently Asked Questions
Why is there standing water in the bottom of my Bosch dishwasher?
Standing dirty water across the tub floor means the drain path is blocked. The most common causes are a clogged filter or a kinked/clogged drain hose, followed by a blocked disposal knockout, a jammed drain pump, or a stuck check valve. A small amount of clean water around the filter, though, is normal on a Bosch.
How do I fix a Bosch dishwasher that won’t drain?
Bail out the water, clean the cylindrical filter, then check the drain hose for kinks and clogs and clear the disposal knockout or air gap. Run a short rinse cycle to confirm. If water still pools, the drain pump or check valve is likely at fault and usually needs a technician.
What does the E24 error on a Bosch dishwasher mean?
E24 is a drainage fault — water isn’t leaving fast enough, usually due to a clogged filter, blocked drain hose, or air-gap/knockout issue. E25 specifically points to the drain pump being loose or blocked. Clearing the filter and hose resolves most E24 cases.
Is a little water in the bottom of a Bosch dishwasher normal?
Yes. A small amount of clean water in the cylinder around the filter is normal and intentional — it keeps the pump seals from drying out. You only have a problem when there is standing dirty water across the tub floor or dishes come out wet and gritty.
Can a clogged garbage disposal stop my dishwasher draining?
Yes. If the drain hose connects to a recently installed disposal, the internal knockout plug may not have been removed, which blocks drainage completely. A clogged disposal or sink air gap can do the same. Clear those before suspecting the pump.
How much does it cost to fix a Bosch dishwasher that won’t drain?
If cleaning the filter and hose does not solve it, a professional diagnostic at Appliance Forever is a flat $89 service call, applied to the repair when you go ahead. You get an upfront quote before any work, and many drain-pump and valve repairs are completed in the same visit.
Bosch still holding water after the DIY fix? Appliance Forever offers same-day dishwasher repair across the GTA, York Region, and Simcoe County. Factory-trained on Bosch and every major brand — your $89 service call is applied to the repair. Call (647) 834-4646 or book online.
