A dishwasher that isn't filling with water most often has a partly closed supply valve, a stuck float, or a failed water inlet valve. Before you assume the worst, know that many models drain or pause for a minute or two at the start of a cycle, and a normal fill is only enough water to cover the bottom of the tub.
Quick diagnosis
| Symptom | Likely cause | First thing to try |
|---|---|---|
| No water at all, just a hum | Supply valve closed or a kinked line | Open the valve under the sink fully and check the line |
| Fills a little, then stops | Float stuck in the raised position | Lift and lower the float; clear debris around it |
| Starts, then sits quietly | Normal starting drain or sensing pause | Wait a few minutes before deciding it's broken |
| Water covers only the sump area | Normal low fill on modern machines | No action needed |
| No water after plumbing work | Debris in the inlet valve screen | Have the valve and screen checked |
| You hear water come in, but the tub stays nearly dry | Water siphoning out through a drain hose with no high loop | Check that the drain hose loops up high under the counter |
A closer look
The water supply
The dishwasher usually connects to the hot water line under the kitchen sink with its own shutoff valve. Plumbing work or a cabinet cleanout can bump that valve half closed. Behind the dishwasher, a supply line can kink when the unit is pushed back into place.
The float
Most dishwashers have a small dome or cylinder on the tub floor, usually in a front corner. It rises with the water and tells the control to stop filling. If food, broken glass or a utensil holds it up, the control thinks the tub is already full. Lift it gently; it should move up and down freely and drop back on its own.
The water inlet valve
This electric valve sits behind the lower kick panel and opens when the control calls for water. It can fail electrically, or its small inlet screen can clog with sediment, especially after water main repairs or house plumbing work. Replacing it means working with water and electrical connections, so leave it to a pro.
Water leaving as fast as it comes in
The drain hose normally rises in a high loop under the counter, or runs to an air gap, before it drops to the sink drain or disposer. Without that rise, water can siphon out during the fill, so the tub never holds enough. This often shows up after a new install or a disposer swap.
Who runs into this most
Homes that just had plumbing or remodel work, new installations, and houses on a street where the water was recently shut off for repairs.
Prevention checklist
- •Clean the filter and the area around the float regularly
- •Keep small utensils in the basket so they can't fall to the tub floor
- •Know where the dishwasher's shutoff valve is
- •After plumbing work, confirm the valve is fully open
Time to call a pro
- •The supply valve is open but the machine hums without filling
- •Water keeps filling without stopping (turn the supply valve off right away)
- •The breaker trips when the fill should start
- •A fault code appears (codes vary by model)
Travis's rule of thumb: Open the valve, lift the float, check the drain loop. If it still won't fill, the inlet valve is next on the list.
Valve open and still no water? Our dishwasher repair page is the next stop, or call (832) 552-1615. A weak fill also leaves detergent behind, which is one reason a dishwasher pod won't dissolve.