Dear Ben Hopkins:
"Ben Hopkins" wrote in message news:gjBvh.16827$ snipped-for-privacy@newsread2.news.pas.earthlink.net...
adding sci.engr.mech
I'm not a physicist, not a scientist, but I have a question
> I think this group can answer.
>
> There's a refrigerator in my uninsulated garage. It has
> a freezer section on the top.
>
> In the summer, it's very hot in the garage (Southern
> California), in the winter it's very cold (sometimes down
> to the 50's (Farenheit)).
>
> In the summer, things freeze in the refrigerator
> compartment if they're on the top shelf (close to the
> freezer section), and the freezer freezes real good. A
> water bottle half full of water freezes up in three to four
> hours.
>
> In the winter, things don't freeze in the refrigerator
> compartment, even if they're on the top shelf, and in
> the freezer section, the water bottle's contents aren't
> completely frozen after 8 hours!
>
> How come? The thermostat has not been changed.
> This is the second winter we've had the fridge in the
> garage, and it was the same last winter.
The configuration of your freezer's cooling system is such that it is most "effective" near a certain temperature differential. Most refrigerant type systems are this way, but will have different differential temperatures. You can alter this differential by some amount by changing the pre-charge in the cooling loop. As refrigerant is lost over time due to leakage, the optimum temperature range changes.
But I think you have "too small" or blocked condensor coil, making it harder to transfer heat that has been collected in the cabinet to ambient. Check your owners manual for installation instructions, including required clearances around and behind the unit, as well as coil servicing instructions.
Other than that... that is about the way it is.
David A. Smith