Temperature zones and the “OK” indicator
The inside of a fridge is not one temperature: cold air sinks and comes out of the vents, so some shelves are colder than others. The diagram shows where each kind of food keeps best; the “OK” indicator shows whether that zone is cold enough.
What the manuals say to do
Put the most perishable food in the coldest zone — Indesit and Miele name meat, fish and cooked food — and butter, cheese and drinks in the warmest, the door and top front. Bosch says that if the sticker does not show “OK”, turn the temperature down gradually; it can take up to 12 hours after switching on.
What it does not mean
It does not mean the coldest zone is in the same place in every fridge: Bosch puts it in front of the air outlets and in the chill compartment, Miele directly above the DailyFresh drawer and at the back, Indesit in the lower area. The “OK” sticker is not a thermometer reading.
Makes differ, check your fridge’s manual: the same drawing can mean different things on different brands, and only your model’s manual says exactly what a button does, what temperature it sets and when it switches itself off.
- What it looks like
- A diagram of the fridge with bands or shelves marked from warm to cold, and on some models a small indicator inside that reads “OK” when it is cold enough.
- Names used
- Chill zones (Bosch); Coldest area / warmest area (Miele); Temperature zone, cool zone, coldest zone (Indesit); Sticker “OK” (Bosch)
Where makers differ
Bosch’s “OK” sticker checks for +4 °C or colder. A fan fridge (Miele DynaCool, NoFrost models) evens out the zones, so the differences are smaller.
Other symbols with the same shapes
Sources
No public standard defines this panel symbol, so its meaning is taken from the manuals of 3 different maker groups (Bosch, Miele, Indesit), each fetched and read on the date shown:
- Bosch: Bosch — Instructions for use, fridge-freezer KGN.. (9001101173 F, PDF) — “The air circulation in the refrigerator compartment creates different chill zones: The coldest zones are in front of the air outlet openings and in the chill compartment.” Sticker “OK”: checks “the safe temperature ranges of +4 °C or colder … If the sticker does not indicate ‘OK’, gradually reduce the temperature.” Checked 2026-09-27.
- Miele: Miele — Operating instructions, fridge-freezer, M.-Nr. 11 746 390 (PDF) — “The coldest area in the fridge zone is directly above the DailyFresh drawer and at the back … The warmest area … is at the top in the front area and in the door. Use this for storing butter and cheese.” With the fan running, the differences are less pronounced. Checked 2026-09-27.
- Indesit: Indesit — Built-in fridge-freezer user manual EIB150502D (PDF, copy hosted by the University of Cumbria) — Upper area and door: temperature zone (drinks, eggs, butter); middle: cool zone (cheese, milk, yoghurt); lower area: coldest zone (cold cuts, meat and fish, home-cooked food); fruit & vegetable drawer at the bottom. Checked 2026-09-27.
Written in our own words; quotations are the regulation’s or the makers’ wording.