Fisher & Paykel Dishwasher Error Code U1

U1 is a fill fault indicating that the wash motor did not prime within the allowed time during the fill cycle. This means the dishwasher could not establish sufficient water flow to begin washing. Causes range from simple issues like a closed water supply valve or low water pressure to a failed inlet fill valve. Checking your water supply and pressure are the recommended first steps.

Resetting the dishwasher may clear the U1 code temporarily, but the fault will return on the next cycle if the underlying cause has not been addressed. Resolve the supply pressure, valve, or installation issue first, then restart the machine. A reset alone is not a fix for a fill fault.

If the fix is simply adjusting the programme from HP to LP or correcting the drain hose routing, there is no parts cost involved. If the inlet fill valve has failed and needs replacement, parts typically cost in the range of $40 to $120 depending on the specific model, with a technician's labour adding $80 to $180 on top of that. Diagnosing the exact cause first will help avoid unnecessary parts purchases.

Start by confirming the water supply valve is fully open and that your home water pressure meets the 50kPa minimum. If the machine is set to the HP programme and your water pressure is low, change the programme to LP. Also check that the drain hose is correctly looped to prevent siphoning and that the spray arm is properly seated. If all of these check out, the inlet fill valve may need to be tested and replaced.

The dishwasher will not complete a wash cycle while U1 is active, so continued normal use is not possible until the fault is resolved. There is no immediate safety hazard from a fill fault, as the machine stops the cycle rather than running without adequate water. However, you should not attempt to repeatedly force the machine through cycles while the root cause remains unresolved, as running the pump dry can damage it over time.