Why is my wine cooler not holding temperature?

What is actually going on

Wine columns fail quietly, and the usual version is a display still showing 55°F over racks sitting several degrees warmer, because the sensor sits where the circulating air still reaches and the bottles do not. When one zone of a dual-zone cabinet holds while the other climbs, the healthy zone has proved the sealed system out, and the fault belongs to the drifting zone: its evaporator, its fan or its damper.

What we check, and in what order

Ambient temperature is the first thing we measure here, and it explains more calls than any component does. A cabinet built into an island in a remodeled cottage kitchen, into a bar wall near Sail Bay, or into an outdoor kitchen is rejecting heat into a space where the air barely moves. On a warm afternoon that unit runs without ever cycling off and still loses two or three degrees. Nothing in it is broken. It has been asked to do something it cannot.

Condensation inside the glass is a separate fault from temperature and gets diagnosed separately. It is the door seal, or the pane heater whose job is to hold the glass above dew point. Both matter more in a coastal kitchen than anywhere inland, because the room spends much of the year close enough to dew point that a small loss shows up as fog on the glass by morning.

If that matches what yours is doing, say so when you call — it decides which parts come on the van.