What Does E24 Mean On A Bosch Dishwasher: Clear Fixes And Tips

If your Bosch dishwasher flashes E24, it’s not trying to send Morse code. It’s telling you there’s a drain problem. I’ve spent years troubleshooting Bosch models in homes and workshops, and I can tell you E24 is one of the most common—and most fixable—alerts. In short, what does E24 mean on a Bosch dishwasher? It signals that the machine can’t drain water properly. The good news: most causes are simple, like a clogged filter, a kinked hose, or a blocked sink connection. Stick with me, and we’ll turn that E24 into a clean, quiet finish.

What E24 Means On A Bosch Dishwasher

E24 on a Bosch dishwasher indicates a drain error. The control board detects that water is not leaving the tub as expected. That can be due to a physical blockage, an installation issue, or, less often, a failing drain pump.

Think of the drain system like a slide at a playground. If the slide is bent, blocked, or sticky, nothing moves. E24 is your dishwasher’s way of saying, “The slide is jammed.”

Key points:

• E24 is a drain issue, not a heating or water-fill problem.
• It often appears early in the cycle or after a pause, when the unit tries to drain.
• It can show up intermittently if the blockage shifts or partial clogs move around.

Common Causes Of The E24 Error

From my experience and manufacturer documentation, these are the usual suspects:

• Dirty filter and sump screen Food bits, seeds, glass, or labels blocking flow at the bottom of the tub.
• Kinked or crushed drain hose The hose behind the dishwasher gets pinched during installation.
• Air gap or sink connection clog The small cap on the sink (air gap) or the garbage disposer inlet is blocked.
• Garbage disposer knockout still in place After a new disposer install, the knockout plug on the dishwasher inlet wasn’t removed.
• Check valve stuck The small flap near the pump or hose connection can get stuck closed.
• Drain pump obstruction Pump impeller jammed by debris like glass or bone.
• Wrong hose routing or no high loop Without a high loop or air gap, water can backflow, confusing sensors.
• Standing water from a previous power outage The machine thinks it’s still draining due to trapped water.

Quick Checks And Easy Fixes

These take minutes and solve most E24 cases:

• Clean the triple filter Twist out the bottom filter assembly. Rinse under warm water. Check the mesh for grease film.
• Inspect the sump Look for seeds, glass, pasta, or labels near the impeller opening. Use a flashlight.
• Check the drain hose Feel behind the unit. Make sure the hose isn’t bent, crushed, or looped too low.
• Clear the air gap If you have one on the sink, pop the cap and clean out gunk with a small brush.
• Verify the disposer inlet Remove the dishwasher hose at the garbage disposer. Ensure the knockout was removed and the inlet is open.
• Run a short drain test Start a rinse cycle and listen for the drain pump. You should hear steady humming and water moving.

Step-By-Step Troubleshooting Guide

Before you begin: Turn off power to the dishwasher at the breaker and close the water supply valve if you’ll be moving the unit.

1. Pull and clean the filter

• Remove the lower rack.
• Twist and lift the filter assembly.
• Rinse and scrub. Reinstall snugly.

2. Check the sump for debris

• Shine a light into the sump opening.
• Remove visible debris with tongs. Avoid fingers near the impeller.

3. Inspect the hose and high loop

• Confirm the hose has a high loop under the counter, secured near the top.
• If connected to a disposer, the hose should rise before it drops to the inlet.

4. Disconnect and flush the hose

• Place a towel and a pan under the connection.
• Detach the hose at the sink/disposer side.
• Run water through the hose in a sink or with a faucet sprayer to verify clear flow.

5. Examine the check valve

• On many Bosch models, a small rubber flapper sits at the drain outlet.
• Ensure it moves freely and isn’t warped shut.

6. Test the drain pump

• With the filter out, locate the impeller opening.
• Look for obstructions. If accessible, spin the impeller gently with a tool.
• Restore power briefly and start a drain cycle to test. Stop if you hear grinding.

7. Reset the dishwasher

• After fixes, hold Start for 3–5 seconds to cancel.
• Or power cycle at the breaker for 5 minutes.
• Run a quick wash to confirm the E24 is gone.

Signs you need a new pump:

• Loud buzzing with no water movement after clearing blockages.
• Burnt smell or visible damage.
• Impeller loose or wobbly.

When To Reset And When Not To

A reset helps after you’ve cleared a clog. It tells the control board to try again. But a reset won’t fix a physical blockage or a bent hose. If you reset first and the error returns, investigate the drain path.

Good times to reset:

• After cleaning filters and the sump.
• After re-routing or replacing the drain hose.
• After clearing the air gap or disposer inlet.

Avoid relying on resets if:

• Water remains in the tub after every cycle.
• You hear the pump straining or grinding.
• The error returns immediately at the start of a cycle.

Preventing E24 In The Future

A few simple habits keep drains happy:

• Scrape, don’t pre-rinse Get rid of the big stuff, but let enzymes do their job.
• Clean the filter weekly Takes 60 seconds and prevents buildup.
• Run hot water first At the sink, run hot water for 10–15 seconds before starting a cycle.
• Use quality detergent Avoid overdosing. Too much soap creates gunk.
• Check the hose annually Make sure it’s not sagging or kinked.
• If you install a new disposer Always remove the knockout before connecting.

Safety Notes And What To Avoid

– Unplug or switch off the breaker before hands-on work Electricity and water don’t mix.
– Don’t stick fingers into the pump housing Use tools and a flashlight.
– Don’t use chemical drain cleaners They can damage rubber parts and pumps.
– Keep the high loop Above the sink drain height to prevent backflow.
– Replace worn parts with OEM or trusted equivalents Cheap parts can lead to repeat errors.

Cost And Parts: What To Expect

If basic cleaning doesn’t solve E24, here’s a rough guide:

• New drain hose Low cost, usually affordable and easy to DIY.
• Air gap Very affordable.
• Check valve Very affordable; quick swap.
• Drain pump Moderate cost; DIY-friendly on many models.
• Professional service Expect a diagnostic fee plus parts and labor. Often worth it if you’re short on time.

Tip from the field: When the pump fails, it often follows a period of noisy draining. If yours has grown louder over weeks, plan ahead and order the part before it dies mid-dinner-party.

Frequently Asked Questions Of What Does E24 Mean On A Bosch Dishwasher

Is E24 Always A Drain Pump Failure?

No. Most E24 cases are clogs or hose issues. The pump is the last thing to replace after you rule out blockages and routing problems.

Can A Clogged Garbage Disposer Cause E24?

Yes. If the disposer inlet is blocked or the knockout plug wasn’t removed, the dishwasher can’t drain and triggers E24.

Will A Hard Reset Fix E24 Permanently?

Only if the underlying cause is gone. A reset clears the error but won’t fix a kinked hose or a stuck check valve.

How Often Should I Clean The Filter?

Weekly for busy kitchens, or at least twice a month. It takes a minute and prevents most drain problems.

What If E24 Appears Mid-Cycle?

Stop the cycle, drain any standing water, clean the filter and sump, and check the hose and air gap. Then run a short cycle to test.

Do I Need An Air Gap If I Have A High Loop?

Local codes vary. A high loop helps, but an air gap offers the best protection against backflow and is required in some areas.

Can Detergent Choice Trigger E24?

Indirectly. Too much or low-quality detergent can create residue that clogs the filter and sump over time.

Wrap-Up And Next Steps

E24 on a Bosch dishwasher means the machine can’t drain. In most homes I visit, a quick filter clean, hose check, and air gap clear fix it fast. When you handle the basics, your dishwasher rewards you with quiet, spotless cycles.

Take 10 minutes today to clean the filter and inspect the hose. If the error sticks around, follow the step-by-step guide above. Still stuck? Call a pro with confidence, knowing what to ask and what parts might be needed.

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