Samsung Dishwasher Error Code nF — What It Means & How to Fix It

What Does This Error Mean?

The nF error on a Samsung dishwasher means 'No Fill' — the machine is not detecting water entering the tub. The dishwasher started a fill cycle but didn't sense adequate water within the expected time. This is very similar to the 4E error and often has the same causes. Most of the time it's a water supply issue — a closed valve, low pressure, or a clogged inlet screen. It can usually be fixed without a technician.

Affected Models

Samsung DW80R9950UG
Samsung DW80R5061US
Samsung DW80N3030US
Samsung DW80M9550US
Various Samsung dishwashers 2018+

Common Causes

Water supply valve under the sink is partially or fully closed
Inlet water hose kinked behind the dishwasher preventing flow
Clogged inlet valve filter screen blocked by mineral deposits or debris
Faulty water inlet valve not opening when the control board signals it
Low home water pressure preventing adequate fill within the timeout period

How to Fix It

Locate the water supply valve under the kitchen sink — it's the valve the thin hose runs from to your dishwasher. Make sure it's fully open by turning it counterclockwise as far as it goes. A valve that's only half-open restricts flow enough to trigger the nF timeout.

If you recently had plumbing work done or the sink faucet repaired, the valve may have been accidentally left partially closed.
Pull the dishwasher forward slightly (if possible) and inspect the water inlet hose for kinks or bends. The hose should have a gentle curve — not a sharp 90-degree bend. Even a slight kink reduces flow significantly.

Dishwashers pushed tightly against the cabinet sometimes develop a kinked hose over time. Ensure there's enough slack for the hose to route without sharp bends.
Turn off the water supply valve, disconnect the hose from the back of the dishwasher, and look inside the dishwasher's inlet port for a small mesh screen. Remove the screen with needle-nose pliers and rinse it clean under the tap. Mineral deposits and debris easily block this tiny filter.

Hard water areas are especially prone to screen blockage. Soak the screen in white vinegar for 10-15 minutes to dissolve mineral deposits.
Check your home water pressure. Run the kitchen sink faucet on hot while the dishwasher is trying to fill. If the faucet pressure is also weak, your home's overall water pressure is low. Samsung dishwashers require a minimum of 20 PSI to fill correctly.

Your water utility company can tell you your home's water pressure. A pressure gauge at the hose bib also works. Normal home pressure is 40-80 PSI.
If all external factors check out, the water inlet valve solenoid has failed. Reset the dishwasher by unplugging it for 5 minutes. If nF still appears immediately when a new cycle starts, call a technician to test and replace the inlet valve.

Inlet valves are located inside the dishwasher at the back behind the lower kick plate, connected to where the supply hose attaches.

When to Call a Professional

If the supply valve is open, the hose isn't kinked, and the filter is clean, the inlet valve itself has likely failed. A faulty solenoid valve won't open even with power applied. Inlet valve replacement costs $80-$175 including parts and labor. A technician can verify valve failure in minutes with a multimeter test.

Frequently Asked Questions

What is the difference between nF and 4E on Samsung dishwashers?

Both codes mean the dishwasher isn't getting enough water, but they indicate slightly different failure points. 4E is the general water supply error, while nF specifically indicates a 'no fill detected' timeout. In practice they have the same causes and are fixed the same way. nF appears on newer Samsung dishwasher firmware, while 4E is used on older models.

How long does a Samsung dishwasher take to fill?

Most Samsung dishwashers fill in 2-5 minutes during a normal cycle. The machine uses a float switch or flow meter to detect when the tub has reached the correct water level. If the water level isn't reached within the programmed timeout period — usually 4-8 minutes — the nF error is triggered. The machine stops to prevent running with insufficient water.

Can hard water cause the nF error?

Hard water itself doesn't cause nF, but the mineral buildup it creates does. Over time, calcium and magnesium deposits clog the inlet valve filter screen and can even clog the valve's solenoid ports. If you live in a hard water area, clean the inlet filter screen every 6 months and consider using a dishwasher descaling tablet quarterly.