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Error code reference

Fisher & Paykel Washer Error Code U1

Fill fault; the motor has not primed after a given time

Fisher & Paykel codesFisher & Paykel washer codes

Fill fault; the motor has not primed after a given time. Possible causes include water supply not turned on, siphoning, sprayarm not in place, excessive foaming, fill valve failed closed, or machine set to HP on a low pressure water supply.

First step from the service manual

Verify the water supply is turned on.

The complete diagnostic procedure includes additional test steps, resistance specifications, wiring diagram references, and component test points.

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What U1 means on a Fisher & Paykel washer

The U1 error code on a Fisher & Paykel washer indicates a fill fault, specifically that the motor has failed to prime within a defined time period. Priming refers to the motor detecting adequate water in the drum to begin agitation or washing. The control board monitors fill progress and triggers U1 when sufficient water volume is not reached before the timeout expires. This is fundamentally a water supply issue, though the root cause can originate at several different points in the fill circuit.

The most straightforward causes are external: the water supply tap being closed, a kinked inlet hose, or a clogged inlet filter screen. Beyond these, the U1 code can also result from siphoning, where water drains back out through the standpipe as fast as it fills in. An incorrectly installed or missing spray arm can also prevent the machine from reading water presence correctly. Excessive detergent causing heavy foam can interfere with water detection as well, since foam does not register the same as liquid water in the drum.

A less obvious but important cause is a machine configured for high pressure operation when connected to a low pressure water supply. Fisher & Paykel washers have an HP setting that affects fill behavior, and running this setting on an inadequate supply pressure will consistently trigger U1. A fill valve that has failed in the closed position is the primary hardware failure scenario and requires valve replacement. Systematic diagnosis should work from the simplest external checks inward toward component-level testing.

Source: manufacturer service documentation.

Common causes of U1

  1. 01

    Water supply not turned on or restricted

    Wiring / connection

    The inlet tap may be partially or fully closed, or the inlet hose filter screens may be clogged with sediment. Check that both supply valves are fully open and inspect the filter screens at the back of the machine where the hoses connect.

  2. 02

    Siphoning through the drain hose

    Wiring / connection

    If the drain hose is inserted too far into the standpipe or positioned too low, water can continuously siphon out during fill. Ensure the drain hose is installed at the correct height and forms a proper loop as specified for the installation.

  3. 03

    Excessive foaming from too much detergent

    Wiring / connection

    Overuse of detergent or use of non-HE detergent in a high-efficiency washer creates foam that does not register as water, causing the machine to time out before priming. Run a rinse cycle with no detergent to clear foam and reduce detergent quantity going forward.

  4. 04

    HP setting used with low water pressure supply

    Wiring / connection

    When the machine is set to the HP (high pressure) mode but the incoming water supply pressure is insufficient, the drum will not fill fast enough to prime within the allowed time. Verify the pressure setting matches your actual supply conditions.

  5. 05

    Fill valve failed closed

    Part replacement

    The water inlet valve may have failed electrically or mechanically in the closed position, preventing water from entering the machine at all regardless of supply conditions. If all external checks pass, the inlet valve should be tested and replaced if found faulty.

See the test procedure for each cause

Frequently asked questions about U1

What does U1 mean on a Fisher & Paykel washer?
U1 is a fill fault code indicating the motor did not prime within the allowed time during a fill cycle. The machine expected to detect water in the drum but could not confirm adequate fill before the timeout expired. Causes range from a closed water tap or siphoning issue to excessive foam or a failed fill valve. Starting with basic supply checks will resolve the majority of U1 errors without any parts replacement.
How do I fix a U1 error on my Fisher & Paykel washer?
Begin by confirming both hot and cold water supply valves are fully open and that the inlet hoses are not kinked. Check the small filter screens at the hose connection points on the back of the machine for sediment blockage. If the machine is set to HP mode, verify your home water pressure is sufficient for that setting. If those checks pass, inspect the drain hose installation for siphoning and evaluate whether excessive detergent foam could be the cause before moving on to component-level diagnosis of the fill valve.
Is it safe to keep using my washer when U1 is displayed?
You should not attempt to run wash cycles while U1 is active, as the machine has detected that it cannot fill properly and the cycle will not complete correctly. Continuing to run the machine without addressing the root cause will not damage it in most cases, but the underlying issue such as a failed valve or siphoning problem should be corrected before normal use resumes.
Will resetting the washer clear the U1 error code?
Resetting the machine may temporarily clear the U1 display, but the code will return on the next cycle if the underlying fill problem has not been corrected. A reset is only useful as part of diagnosing whether an intermittent condition such as a momentary pressure drop caused a one-time fault. If U1 reappears consistently, work through the supply, siphon, foam, and pressure setting checks before assuming a hardware failure.
How much does it cost to repair a U1 error on a Fisher & Paykel washer?
If the fix is simply turning on the water tap, adjusting the drain hose, or reducing detergent use, there is no parts cost involved. If the water inlet valve has failed and needs replacement, parts alone typically range from $30 to $90 depending on the specific model, with professional labor adding $80 to $200 on top of that. Diagnosing and confirming the valve is the fault before purchasing parts is recommended to avoid unnecessary expense.

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