A new cabinet arrives with a display, a set of buttons and no advice. The number you choose matters less than most people expect. What matters is that it stops moving.
Storage: one number, held steadily
For keeping wine rather than serving it, WSET puts the range at 10 to 15 C and stresses constant temperature over any particular value in its storage notes. A cabinet sitting at 14 C for five years does a better job than one that averages 12 C by swinging between 8 and 16.
So pick a number in that band, write it down, and stop adjusting it. Twelve is a reasonable default for a mixed collection because it is close enough to serving temperature for reds and whites alike that neither needs much correction at the table.
What dual zones are actually for
A second zone is a serving convenience, not a storage requirement. Set the lower zone to around 8 C for whites and sparkling you plan to drink soon, and keep the upper zone in the storage band for everything else.
Storing wine long-term at 6 C does no favors. It slows development further than intended and puts white wine below the range where it shows anything, as the serving temperature chart sets out. Cold is not a stronger version of cool.
A kitchen fridge is not a wine cabinet
A domestic fridge runs at 4 to 5 C, is dry, vibrates, and gets opened several times a day. Over months in that environment corks lose elasticity and harden, which damages the seal and can leave a wine stale or a sparkling wine flat.
For a few days before serving it is perfectly fine. As a storage solution it is a slow way to spoil the bottles you were trying to look after.
Check what the cabinet really does
The display reports one sensor in one place. Put a cheap thermometer on the top shelf for a week, then the bottom shelf for a week, and write down the highs and lows. Cabinets commonly run several degrees warmer at the top, and compressor cabinets cycle more widely than thermoelectric ones.
Cabinet and number of zones: Set point: Measured, top shelf, over a week: low / high: Measured, bottom shelf, over a week: low / high: Warmest and coldest shelves: What lives on which shelf: Date checked:
That difference between shelves is not a fault, it is a feature. In a single-zone cabinet, put whites and sparkling low and reds high, and you have a dual-zone cabinet for the price of a thermometer.
When it drifts
Check the reading occasionally rather than trusting the display forever, particularly after a heatwave or a power cut. If it stops holding temperature, the equipment failure guide covers what to move first and what to write down, so that a strange bottle years later has an explanation.
And before buying the next cabinet, the capacity guide covers what a stated bottle count really means once your own bottle shapes are involved.