Storing Food In A Negative Space

I managed a residential property for a housing association. A tenant called down to say that her fridge must be faulty as her milk goes bad too quickly, and she noticed that at her workplace things stored in the fridge are generally colder.

Okay, sounds interesting, up I go.

We open the fridge (brand new, digital display, etc.) and I notice that the temperature is set to 13°C. I tell her that this should be around 3°C to 5°C ideally. She says that she set it to 13°C as she wanted it really cold…

Okay, I tell her that to do that, she has to set it to a lower temperature or higher, which prompts her to laugh at me and say I don’t know how negative numbers work. She was convinced that it’s -13°C…

Okay, I explain to her it’s positive; she doesn’t believe me and says it’s cold in a fridge for a reason and it always has to be minus. I point out that that’s what she has a freezer underneath for, which actually freezes stuff, and also point out that her drinks etc would all be frozen solid if the fridge went under 0°C.

I’m not making this up… she still didn’t believe me, so I had to Google “ideal temperature for fridges” and show it to her. Still in disbelief, she reluctantly agrees to set the fridge to 4°C, so I do just that and leave.

I kid you not, within thirty minutes she calls down that she wants an engineer to visit anyway because even though I’ve set it to 4°C, it’s still not cold.

So, I had to give another lesson about thermodynamics and explain why it takes time for her fully loaded fridge to reach the temperature set, and she’ll need to wait, and I’ll call an engineer only if it won’t change in the next three to four hours.

It was working fine, of course.