In which ambient temperature is it best to place the wine cooler?

This depends on the climate class of the cabinet (found on the type plate inside the cabinet or on the back)

Basic climate classes

N (Normal)
Suitable for rooms with an ambient temperature from +16 °C to +32 °C.
This climate class is often found in energy‑efficient refrigerators for residential use.

T (Tropical)
Suitable for warm environments from +18 °C to +43 °C.
Units in this class typically have stronger insulation and a more robust compressor, allowing them to maintain a low internal temperature even in high heat. Often used in commercial settings.

SN (Subnormal)
Designed for cooler environments from +10 °C to +32 °C.
Suitable for, for example, basements or rooms with a lower than normal temperature.

ST (Subtropical)
Intended for warm and slightly humid environments from +18 °C to +38 °C.
They perform poorly in cold rooms.

Combination climate classes

Since temperature conditions can vary greatly, many units are approved for multiple climate classes. In these cases the climate class covers the full range from the lowest to the highest temperature.

N‑ST
Ambient temperature: +16 °C to +38 °C

N‑T
Ambient temperature: +16 °C to +43 °C

SN‑T
Ambient temperature: +10 °C to +43 °C
This is the most flexible climate class and is often found on units that can be placed in a wide variety of environments.

SN‑ST
Ambient temperature: +10 °C to +38 °C