Whirlpool Washer Error Code F18

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

1. Power & water safety first: unplug the washer and shut off the water supply before you touch anything. This prevents shock and additional flooding.
2. 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.
3. 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.
4. 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.
5. 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.
6. 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.
7. Check the pressure switch and hose: ensure the small air hose from the tub to the pressure/level switch is connected and undamaged. Blocked or pinched hoses can create incorrect water sensing that leads to faults.
8. Run a drain/spin or diagnostic cycle: after drying and re-checking connections, run a drain and spin or the factory diagnostic mode (if you know the procedure for your model) to see if the F18 returns.
   • If the code clears and no leaks are found, monitor the washer over several cycles.
   • If the code returns, document exactly when (start, drain, spin) the code appears — this helps technicians pinpoint the area.
9. Check for control board/wiring faults: if sensors and pumps test OK, the electronic control or wiring harness may be failing and falsely reporting a leak. Inspect connectors and wiring for chafing; replace the control board if diagnostics point to it.
10. When to call a professional: if you find a major structural leak (cracked tub, large seal failure), cannot locate the water source, or you’re uncomfortable working with electrical components, stop troubleshooting and call an authorized Whirlpool service technician.

Maintenance / Prevention Tips

• Inspect and replace inlet and drain hoses every 3–5 years or earlier if cracked.
• Use high-efficiency detergent in recommended amounts to prevent excessive suds and overflow.
• Avoid overloading the washer; excess weight can strain seals and hoses.
• Keep the area under and around the washer clear so small leaks are noticed quickly.
• Periodically check hose clamps and tighten if they loosen over time.
• Run a maintenance wash monthly (hot cycle with no clothes and a washer cleaner) to reduce residue buildup.
• Check the drain line for kinks and ensure it is properly secured to the standpipe or laundry tub.
• Replace worn door boots or gaskets promptly to prevent seepage into the cabinet.
• Inspect the drain pump intake for trapped debris after every few months of use.
• Listen for unusual noises during drain/spin cycles — grinding or rattling can indicate pump issues.
• Don’t push the washer tight against the wall; allow service access and prevent hose strain.
• If you have hard water, consider a water softener to reduce mineral buildup that can clog valves and hoses.
• Ensure the washer is level — an unlevel machine puts extra stress on seals and connections.
• Replace older rubber hoses with braided stainless steel hoses for greater durability.
• Keep the lower access panel in place and periodically inspect the service tray for moisture.
• Have routine professional inspections if the washer is heavily used (multi-family home, shared laundry).

FAQs

Q: Is F18 dangerous?
A: F18 itself is a safety response indicating detected water in the base. The primary danger is potential electrical shorting or floor damage from leaks. Shut off power and water once you spot the error and address the leak promptly.

Q: Can I clear F18 by unplugging the washer?
A: Power cycling can temporarily clear the display, but if the underlying leak or flooded base remains, the code will usually return. Dry the base and fix the leak before resuming normal use.

Q: How much will repairs cost?
A: Costs vary widely: replacing a hose or clamp is inexpensive, pump or sensor replacement is moderate, and tub or control board repairs are higher. Expect anywhere from $50 for a simple part to several hundred dollars for major repairs or labor. Get a quote from a certified technician for accuracy.

Q: Can I keep using the washer after F18 appears?
A: It’s not recommended. Continuing to run the washer risks further leaking, water damage, and electrical hazards. Address the cause before resuming normal operation.

Q: How can I tell if the flood sensor or the pump is bad?
A: Perform a visual inspection and continuity tests with a multimeter if you’re comfortable. If the sensor is wet/corroded or reads out of spec, replace it. If the pump won’t run or is noisy and shows no proper flow even when energized, the pump likely needs replacement. When unsure, call a technician.

Conclusion / Safety Notice

F18 is a high-priority alert because it indicates water has reached areas it shouldn’t — the washer’s protective system is trying to prevent flooding and electrical damage. Always prioritize safety: disconnect power and water before inspecting, and avoid operating the machine if you see active leaks. Simple fixes (tightening a clamp, clearing debris) are often user-serviceable, but structural leaks, cracked tubs, or electrical faults require professional attention.

If you’re not confident working with electrical components, pumps, or internal sensors, contact an authorized Whirlpool technician. Getting prompt, professional service prevents secondary damage and keeps your home safe.