Coffee Maker Not Brewing? 8 Fixes for Drip, Keurig, and French Press Issues

Every 3 months with standard tap water, monthly in areas with hard water (water that leaves significant mineral deposits on faucets and shower heads). The coffee maker starts to require descaling when brewing slows noticeably, when the coffee tastes bitter or sour despite fresh grounds and clean filters, or when the machine displays a descaling indicator. Descaling with white vinegar monthly is safe and effective, the mild acidity dissolves calcium carbonate scale without damaging internal components.

A burnt coffee taste is almost always caused by the hotplate keeping brewed coffee warm for too long. Brewed coffee left on a hotplate degrades with in 20 to 30 minutes, the heat continues to extract and oxidize the oils in the coffee, producing a burnt, bitter taste. Solution: switch to a thermal carafe model (Breville Precision Brewer, Technivorm Moccamaster) that keeps coffee warm without continued heat, or transfer brewed coffee to a preheated thermal container immediately after brewing.

Yes, paper filters placed inside a reusable basket add an additional layer of filtration that produces clearer coffee with less fine-particle sediment. Some users prefer this for cleaner-tasting drip coffee. Use a size 4 paper filter for most 10-12 cup baskets. The combination of a reusable basket (which holds the filter in position) with a paper filter reduces the coffee oil in the cup and produces a cup closer to pour-over quality from an automatic drip machine.

A burning plastic smell from a new coffee maker is typically the protective coatings on heating elements burning off in the first few brew cycles. Run two to three brew cycles with water only and discard the output. The smell should dissipate completely by the third cycle. If the burning smell continues after three cycles or develops in an older machine that previously had no smell, stop using the machine, a burning smell in an older unit indicates an electrical component is failing and creates a fire risk.