Zenith Dishwasher Error Code F20

F20 on a Zenith dishwasher indicates a non-draining sump condition based on turbidity sensor feedback. The control board has determined that water is not properly draining from the sump area, either because a physical blockage or pump failure is preventing drainage, or because the turbidity sensor is not correctly detecting that draining has occurred. The dishwasher will halt the cycle until the fault is resolved.

Running the dishwasher with an active F20 error is not recommended, as standing water in the sump can promote mold, bacterial growth, and unpleasant odors. A non-draining condition may also cause water to pool and potentially overflow during subsequent cycle attempts. Resolve the drainage issue before resuming normal use.

Repair costs vary depending on the cause. Cleaning the filter and drain path costs nothing beyond time, while replacing a drain pump typically ranges from $80 to $200 including parts and labor. A turbidity sensor replacement generally falls in the $50 to $150 range depending on parts availability and local labor rates. Having a technician diagnose the issue first can help avoid unnecessary part replacements.

Start by removing and cleaning the sump filter at the bottom of the tub, as clogged filters are the most common cause. Next, check the drain hose for kinks and verify the garbage disposal or sink drain connection is clear. If drainage still fails, the drain pump or turbidity sensor may need to be tested and possibly replaced. Restoring proper water flow through the drain path is the key to clearing this fault.

A power reset may temporarily clear the F20 code from the display, but the fault will return if the underlying drainage problem or sensor issue has not been corrected. Resetting the unit by cutting power for a few minutes can be a useful diagnostic step to confirm whether the fault is persistent, but it is not a substitute for diagnosing and repairing the root cause.