Most homeowners do not check a softener by looking at the tank. They notice it in the laundry room and at the kitchen sink. Towels feel rough, whites look gray, colors seem to fade faster than they used to, glasses come out of the dishwasher with a cloudy film, and soap seems to vanish without making suds. Those symptoms can point to hard water, but detergent habits and appliance settings cause the same complaints, so the first job is to sort the causes before you assume the softener has failed.
What hard water does to fabric and dishes
Hard water carries dissolved calcium and magnesium. In the washer, those minerals react with soap and detergent and form a residue that does not rinse away well. The result is fabric that feels stiff, whites that look dull, and towels that lose their softness after a few washes. In the dishwasher, the same minerals leave a spotty or cloudy film on glass, and the film gets heavier over time. Hard water does not cause every one of these problems on its own, though, so treat it as one suspect among several.
Start with the pattern, not the symptom
Before you change anything, write down three things: which appliance or fixture shows the problem, which symptom you see, and when you first noticed it. A pattern narrows the cause quickly.
If the problem appears in the washer, the dishwasher, and at the bathroom sink, the water is the most likely common factor. If it shows up only in the dishwasher, look at the dishwasher first. If it shows up only on certain fabrics, look at how those fabrics are washed. If the change started at a specific date that matches a change in your routine, such as a new detergent, a new rinse aid, or a different wash setting, that routine change is a strong suspect.
Check the softener in two minutes
Open the brine tank cabinet and look at the salt level. If the salt is low or missing, the softener cannot soften the water, and hard water returns. Then look at the control display. Confirm that it shows the correct time and that no error or warning code is lit. You do not need to open the valve or check the internals for this step. If the display shows an error, note the code and bring it up when you call for help.
If the salt looks fine and the display looks normal, the softener is less likely to be the cause, but that does not rule it out. Move on to the detergent and the machine settings before you conclude anything.
Check the detergent and dosing first
Too much detergent is one of the most common causes of residue in laundry. Excess soap does not rinse out, and it builds a film on fabric and in the drum. Use the amount the label gives for your water and load size, and do not add extra because the load is large or the clothes look dirty. High-efficiency machines use less detergent and can leave residue when they receive the full dose meant for an older machine.
Fabric softener can add to the buildup. Heavy use leaves a coating that makes towels feel less absorbent, and it can contribute to a dull look over time. Try a load without it and see whether the towels feel different after a few washes.
In the dishwasher, check the rinse aid dispenser. An empty or badly set rinse aid compartment leaves spots. Check the detergent dose and the loading. Dishes that block the spray arm or sit too close to the detergent dispenser can leave residue that looks like hard water. Run one empty cycle with a cup of white vinegar on the top rack if you want to see whether the glass clears, but treat that as a cleaning step, not a diagnosis.
Check the machine and the water temperature
Cold water dissolves detergent less well than warm water. If every load is washed cold, detergent residue is more likely to stay in the fabric. Look at the wash setting you use most, and compare it with the detergent's directions. An overloaded washer also cannot rinse well, so a full drum of towels can look stiff even when the water is fine.
Recognize the signs that point somewhere else
Rust-colored or orange stains on fabric and dishes usually point to iron in the water or to rusty pipes, not to hard water alone. Iron stains look different from the white or gray film of hard water. If you see staining of that kind, the next step is a water report, not a change to your detergent. Dark specks that come from the water heater are a different problem, and they are covered in a separate guide on this site.
A sudden change across every water use in the house, along with a softener that displays a warning, deserves a closer look at the equipment. A slow change that affects only one appliance or one type of fabric usually points to habits or settings.
When to stop guessing and get a test
If the salt is fine, the display is normal, your detergent dose is correct, the rinse aid is working, and the symptoms still show up in every water use, the next step is to test the water before and after the softener. That tells you whether the softener is treating the water or not. Bring your written pattern, the salt level, any display code, and the detergent and rinse aid you use. A technician or tester can act on those facts much faster than on a general complaint about towels or glasses.