Fisher & Paykel Dishwasher Error Code A1

When a Fisher & Paykel dishwasher (including DishDrawer™ models) throws Error Code A1, it’s telling you the machine can’t get water. In everyday terms: the unit tried to fill, didn’t see the expected water level or flow change, and stopped the cycle to protect the pump and heater. The good news—A1 is usually caused by something simple and fixable at home.

What A1 Actually Means

A1 is a no-water or water-inlet fault. The control opened the inlet valve, waited for water to arrive, and didn’t detect a proper fill. Sometimes the tap is closed after a remodel; sometimes a hose is kinked behind the cabinet; other times the inlet screen is clogged with sediment. Less commonly, the inlet valve itself has failed or household water pressure is too low for the fill sensor to register.

You’ll typically see the code soon after a cycle starts. You might also notice the machine humming briefly with no water swishing, or it may pause and beep, then throw A1.

Why It Happens (Plain English)

Dishwashers need a clear path from your shutoff valve to the inlet valve inside the machine. Anything that pinches, blocks, or starves that path will trigger A1. New installs are frequent culprits because the under-sink tap never got fully opened, or the supply line looped too tightly and kinked when the unit was pushed back.

Common triggers include:

• Closed or partially closed under-sink valve
• Kinked or crushed inlet hose behind the dishwasher
• Sediment clogging the inlet screen or valve
• Low water pressure from the home supply or a restricted saddle valve
• A failing inlet valve coil that opens weakly or not at all

Safety First, Then a Quick Reset

Turn the dishwasher off, wait a minute, then turn it back on and try Cancel/Drain to clear any queued cycle. A power reset at the breaker for five minutes can clear false alarms. If A1 returns right away, move to the steps below.

Smart DIY Steps (Minimal Tools)

1. Open the water tap fully
   Under the sink, confirm the dishwasher’s shutoff valve is fully open. Quarter-turn ball valves should be parallel with the pipe; multi-turn valves should be turned all the way counterclockwise.
2. Straighten the inlet hose
   Gently pull the dishwasher forward a few inches. Check the inlet hose for sharp bends or a crush point where it passes through cabinetry. Re-route with a smooth arc so it won’t kink when you slide the unit back.
3. Bleed cold water at the sink
   Run the cold water for 20–30 seconds to flush air and sediment, then start a quick cycle. Sometimes air in the line or debris at startup is all it takes to set A1.
4. Clean the inlet screen
   Shut off the under-sink valve. At the dishwasher connection or at the valve body (depends on model), there’s usually a tiny mesh filter. Remove the supply hose, tease out the screen, and rinse sediment under running water. Reinstall carefully so the O-ring seals.
5. Check household water pressure
   If faucets sputter or flow is weak, your pressure may be low. Dishwashers typically want 40–60 psi. If pressure seems fine elsewhere but the dishwasher still throws A1, the inlet valve may be sticky or electrically open.

If you’re comfortable with a multimeter, you can test the inlet valve coil (with power off, harness disconnected). A reading of “open” (infinite resistance) usually means the valve is bad. If you’re not set up for this, skip testing—don’t guess; move to service.

When DIY Isn’t Enough

If A1 keeps returning after the checks above, it’s time for a thorough diagnosis. A technician will verify water pressure at the tap, inspect the hose path, test valve operation under load, and confirm the control is energizing the valve correctly. On DishDrawer™ units, they’ll also confirm fill detection logic at the correct drawer and inspect internal hoses for restrictions.

Keep A1 From Coming Back (Practical Prevention)

Good habits make a big difference—even in hard-water areas.

• Full-open supply: After any plumbing work or move, re-check the under-sink valve position.
• Gentle routing: Leave a soft loop in the inlet hose; avoid tight corners and sharp cutouts in cabinetry.
• Sediment control: If you get frequent clogs, consider a simple inline sediment filter or flush the line before reconnecting the dishwasher after plumbing repairs.
• Seasonal awareness: In cold climates, prevent partial freezes in exterior walls—low flow from a chilly pipe can mimic low pressure.
• Annual quick check: Pop the toe-kick, shine a flashlight, and make sure the hose and wiring are tidy and dry.

Quick Action Plan

Start simple: open the valve, unkink the hose, flush the line, clean the inlet screen. If A1 still flags after a fresh start, the inlet valve or control-side detection likely needs attention. Don’t keep restarting the same failed fill—get it properly checked so the dishwasher can heat and wash on-spec again.

If you’d like, share your exact model number and what you’ve tried so far—I can tailor the next steps to your Fisher & Paykel series (including exact screen location and the right order of panels to remove).