Machine Use
The frequency of using the machine can determine how potentially damaging the humidity and steam can be to your cabinet. If you use your coffee every weekday, sometimes more than once each day, your chances of steam damaging your cabinet is increased. If you are someone who only uses the coffee maker several times over the course of a month, it is unlikely that your coffee maker will do any substantial damage to the cabinet. After use, gauge the temperature of the space on your cabinet above the coffee maker. If it feels hot or overly moist, you may need to change where you locate your coffee maker.
Distance and Positioning
Where your coffee maker is used can make a difference on the impact it has on your kitchen cabinets. A factor to consider is the distance between the top of the machine and the cabinet. The more vertical distance you can provide between your machine and furniture, the more protected it will be. Place the coffee maker in a place where the steam can rise unobstructed. Create room for the steam to rise by pulling the machine out from the wall when in use. Once the coffee is brewed and the top reservoir has cooled, you can slide it back in place underneath the cabinet against the wall.
Cabinet Material
The materials your kitchen cabinets are made of can determine the effect the coffee maker will have. High-quality wood can endure some humidity and moisture, but repeated exposure can cause the wood to swell up and warp over time. A thick finish to your wood can better protect it from the humidity and steam caused by coffee makers. If your kitchen cabinet is made of laminate, the steam from the coffee maker can cause the glue affixing the covering in place to separate from the cabinet. There is also the potential for plastics to melt after exposure to prolonged heat.
Temperature
Different coffee makers will heat up to different temperatures, so it is likely one maker could cause damage while others may not. If you see excess moisture bead up on the surface of the cabinet, this could be a sign of excess heat and steam. Wipe it clear with a towel to avoid having the cabinet absorb the liquid. A number of different coffee makers are available today that do not require high heat to brew; rather, they cold-brew the coffee overnight. If steam is a concern, a cold-brew machine might be for you.