Determine compressor size from cooling capacity

[kurtz]

I am trying to refrigerate a relatively small space. It is 7 feet X 5 feet and 2 inches tall (a thin rectangular, space that contains the evaporator coil). Based on insulation, with some thermal bridging through the steel structure, an inside temp of 20 F, and ambient of 70 F (which actually will be constant), I calculated my cooling load as approximately 200 Btu/hr. I suppose I would like the capacity to handle 500 Btu/hr.

Do I need to calculate my evaporator surface area first, and try to figure out heat transfer rates for the moving phase changing refrigerant,, or are there data sheets showing compressor size based on cooling capacity for something this small?

Any help would be much appreciated,
danke

[Peter_1]

YOU should select a condensing unit which will give you a capacity of 500 Btu/hr at a condition , of 12°F to 10 F evaporating and 80°F to 85°F condensing
Evaporator should give 500 Btu at an evaporating temperature of 12°F in an ambient of 20°F

Kein danke

[chemi-cool]

Copeland USA makes such small condensing units.