Your ice is only as good as the water going in. A filter is the cheapest fix you'll buy.

Hard water carries minerals. When water freezes on the evaporator plate, the minerals stay behind as scale.

Scale causes a chain of problems.

• Ice sticks to the evaporator and won't drop, so the machine makes less.
• Water lines, valves and sensors clog.
• The machine runs longer cycles and uses more power.
• Cubes come out small, soft, cloudy or uneven.

Much of the Midwest has hard water. Without a filter, scale builds on the plate between every cleaning.

Most ice machine filters do three things.

1. Catch sediment. Sand and rust from the pipes stay out of the valves.
2. Cut scale. A scale inhibitor slows how fast minerals stick to the plate.
3. Take out chlorine taste and smell. Guests notice ice that tastes like the tap.

A filter doesn't replace cleaning. It stretches the time between problems.

Every filter cartridge lists a life in months or in gallons. Follow whichever comes first. A busy store with a big machine uses up a filter faster.

Write the date on the cartridge when it goes in. It's the easiest way to know when it's due.

Signs a filter is overdue:

• The machine fills slowly or makes less ice
• The ice tastes or smells off
• Cubes are cloudy or smaller than normal
• The pressure gauge on the filter head, if there is one, reads low

Even with a filter, an ice machine needs descaling and sanitizing. The manufacturer's manual sets how often. In hard water, many kitchens do it every six months or sooner.

Clean the bin too. Ice is food, and the bin is a food contact surface. Wash the scoop daily and keep it out of the ice.

Ice machines aren't the only ones. Steamers, combi ovens and coffee brewers all scale up from hard water. If your ice machine needs a filter, the rest of the water-using equipment likely does too.