My coffee started tasting off. Bitter in a way that was not the beans. I blamed the roast, switched brands twice, then realized I had not cleaned the machine in over a year. The reservoir had a faint brown film. The basket was sticky with old coffee oils.

Coffee makers collect oil residue and mineral scale that turns your morning cup rancid. You do not need a special cleaning solution. You already have what you need.

The Vinegar Cycle

Fill the water reservoir with equal parts white vinegar and water. Run a full brew cycle without coffee in the basket. Halfway through, turn the machine off and let the vinegar sit for 30 minutes. This gives it time to dissolve the scale inside the heating element. Then finish the cycle.

The Rinse Cycle (Do Not Skip This)

Run two full cycles with plain water after the vinegar. You want every trace of vinegar rinsed out. If your first cup after cleaning tastes like salad dressing, you rushed the rinse.

Clean the Carafe and Basket

The glass carafe gets coffee stains that regular dish soap does not touch. Fill it with warm water, drop in a dishwasher tablet, and let it soak for an hour. The enzymes in the tablet break down coffee oils. Scrub the basket with hot water and dish soap — a bottle brush works great for the corners.

How Often?

Every three months if you brew daily. Every month if your water is hard. You will taste the difference immediately — clean machine, clean cup. If your coffee suddenly tastes burnt or sour, try cleaning before you blame the beans.