Fisher & Paykel Washer Error Code “SuD LoC”

When a Fisher & Paykel washer throws SuD LoC, it’s telling you there’s too much suds in the system. Extra foam cushions the water, confuses temperature and water-level sensing, slows draining, and can stall the cycle. The good news: most SuD LoC events are easy to clear with a reset rinse and a few housekeeping steps.

What “SuD LoC” Really Means

In plain English, the washer thinks it’s washing bubbles instead of clothes. High-efficiency machines are tuned for low-sudsing HE detergents; when they see a mountain of foam or the temperature/pressure signals don’t behave like real water, they pause and trigger SuD LoC to protect the motor and pump.

You might notice the cycle stretching on, a cool tub at times when you expect heat, or a load that finishes with residue and a soapy smell.

Why It Happens (Most Common Triggers)

• Too much detergent for the soil level or load size.
• Non-HE detergent (or DIY mixes) that foam heavily.
• Very soft water amplifying suds even at normal doses.
• Rinse boosters or oxygen additives stacked on top of a full dose.
• Drain setup issues (high standpipe, partial siphon) that confuse sensing and leave suds behind.

Quick Recovery (Simple, Safe, and Usually Enough)

Start gentle—no tools required.

1. Let the foam collapse.
   Pause and wait ~20 minutes so bubbles break down naturally.
2. Run a Deep Rinse.
   Choose a Deep Rinse / Extra Rinse to flood and flush the tub. If your model allows, add one more rinse for stubborn suds.
3. Clear the drain path.
   Make sure the drain hose isn’t kinked and the standpipe height is within spec. As a rule of thumb, max ~1200 mm (≈47 in.)—beyond that, draining slows and foam lingers. (Exact limits vary by model—check your use & care guide.)

If SuD LoC returns immediately after a deep rinse, move to the next section.

Smart DIY Steps (Only a Few, and They Work)

Keep this practical and light; you don’t need to strip the machine.

• Right-size the dose. For most HE liquids in average water: start at 2–3 teaspoons (10–15 mL) for small/medium loads, 1–2 tablespoons (15–30 mL) for large or heavily soiled. In soft water, halve that. Pods count as a full dose—don’t add extra liquid.
• Switch to true HE. If the bottle doesn’t say HE, retire it. Enzymatic HE formulas clean with less foam.
• Rinse-aid & boosters in moderation. Oxygen boosters and pre-soaks add surfactants. If you use them, drop your main detergent dose.
• Warm rinse once. A warm deep rinse can reduce surface tension and help collapse foam (skip this for delicates that require cold).
• Run a Drum Clean. Monthly Tub/Drum Clean (with a washing-machine cleaner or 1–2 cups of white vinegar) dissolves film that promotes sudsing.

If you’ve corrected dosing and plumbing but SuD LoC still crops up, there may be sensor noise or trapped foam in the air-trap/pressure system. That’s a good time to schedule a professional check.

Less Lists, More Plain Talk: What’s Actually Going On

Your washer should see water level and temperature change in predictable ways. With excess suds, the pump cavitates (spins in foam, not water), the pressure signal gets inconsistent, and heating can stall because sensors don’t “see” real liquid contact. The control pauses the cycle and posts SuD LoC so the foam can die down and the machine can save the pump and motor from working dry.

When It’s Not Just Detergent

Occasionally SuD LoC is the symptom, not the cause:

• A standpipe that’s too high or a partially blocked drain leaves wash liquor in the tub, building foam with every tumble.
• A leaky or misrouted drain hose can create a siphon effect, pulling water out too fast and confusing level sensing.
• Pressure hose/air-trap partially clogged with lint or detergent gel can delay level changes and “look” like suds to the board.
• Rarely, a thermistor or control issue misreads temperature/level and flags an over-suds condition incorrectly.

In these cases, a tech will clear the air-trap, verify pressure readings, check the thermistor, and confirm the drain height and hose routing.

Preventive Habits That Keep SuD LoC Away

• Dose for the real load, not the basket size. Light soil = light dose.
• Mind water softness. If you have soft or softened water, cut detergent by 30–50%.
• Pre-treat smart. Pre-treat stains on fabric, not by over-pouring into the dispenser.
• Keep the door gasket clean. Wipe leftover suds and lint after heavy loads.
• Monthly Drum Clean. Keeps sensors clear and residue from building a “foam factory” on the drum walls.
• Check the install once. Verify standpipe height (≤ about 47 in / 1200 mm), secure the drain hose, and avoid tight bends.

Quick Action Plan (Bookmark This)

• Pause → wait ~20 min → Deep/Extra Rinse.
• Fix the dose (HE only, tablespoon—not coffee cup).
• Confirm standpipe height and hose routing.
• Run a Drum Clean cycle.
• If SuD LoC repeats with correct dosing and plumbing, book a pro to inspect the pressure/air-trap circuit and drain path.