Whirlpool Washer Error Code F18 — What it Means
The F18 error on many Whirlpool washers signals that the machine has detected water where it shouldn’t be — typically in the base or the service tray under the tub — or that the washer’s flood-detection/flood-sensing system has been triggered. When the washer senses water in the base it will usually stop the cycle and display the F18 code to prevent further flooding or electrical damage. This safety response can lead to interrupted cycles, longer overall wash times as the machine attempts to drain, and in some cases visible water on the floor. If left unaddressed, leaks can cause damage to flooring, create mold, and create electrical hazards or progressive damage to internal parts (pump, seals, and electronics).
Common Causes
- Leaking inlet or drain hoses (loose, cracked or damaged)
- Clogged, damaged, or failing drain pump or pump housing
- Faulty flood sensor / water detection sensor or malfunctioning float switch
- Cracked tub, door boot (front-load) or door seal allowing water into the base
- Loose hose clamps or plumbing connections
- Blocked or kinked drain line causing overflow or backup
- Failed water level/pressure switch or associated tubing
- Control board or wiring faults reporting a false leak signal
- Overuse of detergent causing suds and overflow into the base
Troubleshooting Steps
- Power & water safety first: unplug the washer and shut off the water supply before you touch anything. This prevents shock and additional flooding.
- Check for visible leaks: inspect the inlet hoses, drain hose and clamps at the back of the washer for obvious cracks, loose clamps or water residue. Replace hoses or tighten clamps if needed.
- Remove standing water and dry the base: if safe to do so, tip the machine slightly (with two people) or remove the lower access panel to inspect and mop out any water collected in the base or service tray. Allow the base to fully dry before powering up again.
- Inspect the drain pump and filter: remove obstructions (coins, debris, lint) from the pump housing and check the pump impeller for damage. A partially blocked pump can cause backup and trigger the flood sensor.
- Check the flood sensor / water detection assembly and wiring: look for corrosion, loose connectors, or waterlogged wiring. Clean and reseat connectors; replace the sensor if visibly damaged or yielding no continuity when tested.
- Examine the door boot and tub seals (front-load): inspect for tears, punctures, or gaps allowing water into the cabinet base. Replace worn bellows or seals as needed.
- Check the pressure switch and hose: ensure the small air hose from the tub to the pressure/level switch is connected and undamaged. Bloc