No Water Entering Dishwasher? Inlet Valve and More

Start with the water supply line

The most common reason a dishwasher does not fill is that water never reaches the machine. Check the shutoff valve under the sink, usually a quarter-turn or compression valve, and turn it fully counterclockwise. If that valve was accidentally closed during a recent repair or while working under the sink, opening it restores flow.

Inspect the supply line from the shutoff to the dishwasher. A kink, a sharp bend, or a pinch can reduce flow enough that the dishwasher thinks there is a problem and skips the fill. Also look for signs of a frozen line if the dishwasher sits in an unheated space. For more on the plumbing, see our guide to the dishwasher supply line.

• Open the shutoff valve fully and listen for water movement.
• Straighten any kinks or loops in the supply line.
• Check that the line is not crushed between the cabinet and the dishwasher.
• If the line is frozen, thaw it gradually and seal any gaps in the cabinet.

Inlet screen and inlet valve

At the point where the supply line connects to the dishwasher, most models have a small mesh screen inside the inlet fitting. Sediment, scale, or rust particles from the household pipework can collect on this screen and slowly reduce water flow until the dishwasher no longer fills. Turn off the water supply, disconnect the hose, and pull the screen out. Rinse it under running water and gently scrub with a soft brush if needed.

The inlet valve, which is a solenoid-operated valve, controls the water that enters the tub. When the control board sends power to the valve, it opens and lets water in. If the valve does not open, no water enters. A stuck valve can happen if the solenoid coil fails, the plunger is stuck, or a small piece of debris holds it closed. Testing the valve with a multimeter for coil continuity is the definitive check. If the valve is dead, replacement is a common DIY task; see our step-by-step replacement guide.

Float switch and water level

The float switch is a safety device that sits in the bottom of the dishwasher tub. It rises as water fills and, when it reaches a set level, it signals the control board to stop the fill. If the float is stuck in the raised position, the machine believes there is enough water and never opens the inlet valve. Look inside the tub and press the float down gently; it should move with little resistance and spring back.

Sometimes the float switch is not stuck but the float chamber has accumulated debris, or the switch contacts are dirty. Cleaning the float area and verifying the switch operates with a multimeter are simple steps. For a step-by-step cleaning procedure, see our float switch cleaning guide. If the switch itself is faulty, you can replace it; follow our replacement guide.

Other causes and advanced checks

If the inlet valve, float, and supply line all look healthy, the problem may be in the control system. A damaged door latch or door switch will prevent the dishwasher from starting any cycle, including the fill phase. Check that the door closes fully and that the latch engages with a solid click. A broken door switch will need replacement.

A failing control board or a wiring fault can also stop the fill signal from reaching the inlet valve. Look for error codes on the display or blinking lights, then consult the manual or a troubleshooting resource. In older machines, a faulty timer or water level pressure switch may be the culprit. If you suspect the control board, you can try a reset by unplugging the dishwasher for a few minutes.

Also verify that the dishwasher is not accidentally set to a delay start or a cycle that skips the initial fill. Some models have an air gap or a high loop that can trap air and prevent water flow; if this is the case, run the sink faucet briefly to clear the air.

Prevention and maintenance

To keep water flowing reliably, clean the inlet screen every few months, especially if your home has hard water or older pipes. The water inlet filter cleaning guide explains how to do it without removing the machine.

Check the supply line for kinks whenever you move the dishwasher or after any work under the sink. If you notice any damage, replace the hose. For guidance on choosing a new hose, see our water inlet hose replacement guide. Using a water softener can reduce scale buildup inside the valve and screen; learn more about water hardness and its effects.

What to pick for your use

Questions

Why is my dishwasher not filling but I hear a humming sound?

A humming sound usually means the inlet valve is receiving power but the valve is blocked, either by a stuck plunger or a clogged screen. Turn off the water, clean the screen, and if that does not help, test the valve's continuity and replace it if needed.

Can a clogged float switch cause a no-fill condition?

Yes. If the float is stuck in the raised position, the dishwasher thinks the tub is full and will not open the inlet valve. Clean the float area and make sure it moves freely.

How do I know if the inlet valve is actually bad?

With the dishwasher unplugged and the water off, disconnect the supply line and use a multimeter to check for continuity across the two solenoid terminals. If there is no continuity, the valve coil is open and needs replacement. You can also apply 120V AC briefly to the valve with the water off and listen for a click, but this is riskier.

What should I do if the water supply line is frozen?

If the line is frozen, do not force the valve open. Gradually warm the line with a hair dryer or a warm towel. After the line thaws, check for leaks before running the dishwasher. Seal any cold-air gaps in the cabinet to prevent future freezing.

Is it worth replacing the inlet valve on an old dishwasher?

If the rest of the dishwasher is in good condition and the valve is the only issue, replacement is often a simple and cost-effective fix. If the machine is old and has other recurring problems, you may prefer to invest in a new unit. Our buying guides can help you compare current models.