A Neff dishwasher showing the tap symbol is warning you that something is wrong with the water supply to the machine. In most cases, the dishwasher is not getting enough water, is filling too slowly, or is being blocked by a safety or hose issue.
What the Neff tap symbol means
The tap icon is a “check water” indicator, not just a decorative light.
- It turns on when the dishwasher detects that filling with water is incomplete, too slow, or has failed.
- It can appear at the very start of a wash if the tub does not begin to fill, or part‑way through a cycle if water flow suddenly drops.
- On some models, the tap symbol may show together with a code or other lights, but the meaning is always related to water supply or flow.
The dishwasher uses this symbol to protect itself and your dishes, because it cannot wash properly without the correct amount of water.
Simple checks to do first
Before opening panels or thinking about parts, run through the easy, no‑tools checks that solve many tap‑symbol complaints.
- Confirm the water tap is fully open
- Locate the valve under the sink or in the cabinet that feeds the dishwasher.
- Turn it fully off, then fully on again to make sure it is really open internally.
- Look for a kinked inlet hose
- Gently pull the dishwasher forward if possible and inspect the supply hose.
- Make sure it is not sharply bent, crushed, or trapped behind the unit or pipework.
- Straighten any tight bends so water can flow freely.
- Try a basic reset
- Switch the dishwasher off at its power switch and at the wall or breaker for a few minutes.
- Turn the power back on, then start a fresh program and watch whether the machine begins to fill normally.
If the tap symbol clears after these checks and the cycle runs with normal filling sounds, the problem was likely a simple restriction or a brief glitch.
Checking water flow and the inlet filter
If the symbol remains, the next step is to confirm that the machine is seeing good water flow and that the inlet filter is clean.
1. Test water flow from the household tap
- Turn off power to the dishwasher.
- Close the dishwasher’s feed tap, then disconnect the inlet hose from the tap connection.
- Hold the hose or tap over a bucket or bowl.
- Open the tap briefly and check that water flows out strongly and steadily.
Weak or dribbling flow here points to a plumbing or valve problem rather than a dishwasher fault.
2. Clean the inlet hose filter at the machine
Most Neff dishwashers have a small mesh strainer where the inlet hose screws into the appliance.
- Turn off the water at the tap and unplug the dishwasher.
- Unscrew the inlet hose from the back or side of the machine.
- Carefully pull out the small mesh filter sitting in the valve port.
- Rinse the filter under running water and gently brush away grit, sand, or limescale.
- Re‑insert the clean filter, reconnect the hose, open the tap fully, and run a test cycle.
A clogged inlet filter is a very common cause of the tap symbol because it chokes the flow even though the household tap is open.
Internal causes: valves, safety systems, and pressure
When external supply and filters are fine, the tap symbol often points to internal water‑path issues.
1. Inlet valve or AquaStop faults
Neff machines may use a standard inlet valve or a safety hose system.
- The electric inlet valve controls how much water enters the dishwasher; if its coil fails, or the valve jams shut, the tub will not fill.
- AquaStop safety hoses shut off the water if a leak or hose failure is detected; once triggered, they block the supply and can leave the tap symbol on.
Testing these components usually involves checking for voltage at the valve during fill and may require part replacement.
2. Low or unstable water pressure
Even if water flows, low or fluctuating mains pressure can cause fill‑time errors.
- If the pressure is too low, the dishwasher may not reach its target fill level within the allowed time.
- Heavy demand in the home (washing machines, showers, garden hoses) can cause temporary low pressure.
If the tap symbol mainly appears at busy times and disappears when water demand is lower, low pressure is a likely factor.
3. Internal blockages and leak‑protection
On some Neff platforms, drain or leak issues can interact with the tap warning.
- Water in the base tray can lift a safety float switch; the machine then stops normal operation, may run the drain pump constantly, and shows warning lights.
- Severe blockages in the drain or sump can confuse the control’s water‑level checks.
If you hear the drain pump running continuously with the tap symbol on, or see water in the base, leak protection or serious blockage is probably involved.
Practical DIY checks inside the dishwasher
These are simple, owner‑friendly checks that can remove hidden restrictions and help the machine work normally again.
- Clean the filters and sump
- Remove the bottom rack and lift out the filter system.
- Rinse the filters and remove food, glass, seeds, or labels from the sump area.
- A clear sump and filter help both filling and draining happen as designed.
- Make sure spray arms move freely
- Spin the spray arms by hand to ensure they are not obstructed.
- Although spray arms themselves do not cause the tap light, blockages and poor circulation can stress the water system overall.
- Check under the sink for proper hose routing
- Ensure the inlet and drain hoses are not tangled around each other or clamped by other plumbing.
- Avoid tight bends and keep hoses supported so they do not sag and trap water or air.
These steps often improve overall water behavior and can help prevent the tap warning from returning.
When to call a professional
Not every tap‑symbol fault is suitable for a DIY fix. Calling a technician is sensible when:
- You have strong water flow at the tap and a clean inlet filter, but the dishwasher still does not fill.
- The tap symbol returns immediately at the start of a cycle, every time, after resets and basic checks.
- You suspect a failed inlet valve, AquaStop safety hose, or internal leak but are not comfortable working with live electrics or removing panels.
- The base tray contains water, or the drain pump runs constantly with the tap symbol lit.
A trained appliance engineer can safely test valves, sensors, float switches, and wiring to confirm which part is at fault and whether repair or replacement is the better option.
FAQs: Neff dishwasher tap symbol
1. What exactly does the tap symbol indicate on my Neff dishwasher?
It is a water‑supply warning that means the machine is not filling correctly, either because there is no water coming in, too little water, or filling is taking too long.
2. My tap is fully open, but the tap symbol is still on what should I do?
Check that the inlet hose is not kinked, test water flow from the tap into a bucket, and clean the small inlet filter where the hose connects to the dishwasher.
3. Can a dirty inlet filter cause the tap symbol?
Yes. A clogged inlet filter restricts water flow enough that the dishwasher may time out during filling and turn on the tap warning light.
4. Does low water pressure trigger the tap icon?
It can. If your mains pressure is very low or drops when other appliances are running, the dishwasher may not reach its fill level in time and will show the tap symbol.
5. Could the tap symbol mean there is a leak?
On models with a base‑tray float or AquaStop system, a leak can cause the safety system to shut off water and display the tap or “check water” warning.
6. When should I stop troubleshooting and call a technician?
If you have confirmed good water flow at the tap, straight hoses, and a clean inlet filter but the dishwasher still will not fill and keeps showing the tap symbol, professional diagnosis of the valve, AquaStop, or internal sensors is the safest next step.
