Customer gave me a used 21 cu ft Sears fridge. (Freezer on the top, refrigerator on the bottom.) I put it in the garage for a spare and have been monitoring the air temps in the refrigerator and freezer compartments.
The air temp in the refrigerator is at 36 when it shuts off on the stat, but goes up to about 43 before it kicks back on.
The air temp in the freezer is at 1 when it shuts off and it kicks back in at 11.
Is this too great a differential?
Not to bad, 43 seems a littly high though.See how long a tomato will last.
most refridgerator cold controls are set around a 4 - 6* differential, so yours is just about inline. this amount of differential is needed, to prevent short cycling of the compressor, since many variables, such as frequency of door openings, temps of products added to the box, etc. can increase a small boxes temperature quickly; quite possibly before the pressures have equalized; if the diferential is less than 4*
interestingly, one of the first signs i see on failing cold controls is irratic cycling, usually at a less than 4* differtial, and subsequent short cycling of the compressor. this is a result of the burning and pitting in the controls contacts and subsequent make and break at the points due to thermal expansion from the heat of the arcing at higher resistance contacts.