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How to find tonnage or KW, EER of refrigerator

How to find tonnage or KW, EER of refrigerator

(OP)
Why do refrigerators doesnt quote the rating in tons . How to calculate the EER and Tons from the data available on the plate attached to refrigeraor.

RE: How to find tonnage or KW, EER of refrigerator

You should call the manufacturer and ask him this question.

Failing that, ask a senior person in your office.

RE: How to find tonnage or KW, EER of refrigerator

The information is likely not listed because it is not required to be listed by Indian law.

From the information on your picture it is not possible to calculate the capacity.

RE: How to find tonnage or KW, EER of refrigerator

Cooling capacity for a refrigerator is really not a necessary piece of information to the buyer. All the buyer needs is the climate class that matches their usage climate, and they'll know that the refrigerator will keep food cold and the freezer will freeze food. An air conditioner is different, because the buyer needs to know how big a room or house they can cool, using rules of thumb like 1 ton per 700 sq.ft. of living space.

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RE: How to find tonnage or KW, EER of refrigerator

If you can make a rough estimate of the COP of this refrig cycle for R134a, then it should be possible to get some idea of the refrig capacity. R134a is stated to be similar to R12 in refrigeration behavior.

For example, if COP is approx 2.5 for an air cooled condensor condensing at 100degF, evaporating at -30degF, then refrig capacity, peak would be 105 x 2.5 = 263W = 897Btu/hr = 0.075tons refrig capacity

While refrig capacity, normal, continous, assuming the compressor runs for say 30% of the time = 263 x 0.3 = 79W = 269Btu/hr = 0.022tons refrig capacity

COP would of course be better in winter and lower in hot weather. Net cooling capacity would also depend on insulation from ambient heat leak into the fridge.

1 ton of refrigeration capacity = 12000Btu/hr

COP = Net refrig effect (sat vap enthalpy - sat liquid enthalpy, Btu/lb)/ heat of compression, Btu/lb



RE: How to find tonnage or KW, EER of refrigerator

The trial value of 2.5 for the COP is taken from table 12-7 in Perry Chem Eng handbook 6th edition for R-12 operating at 100degF condensing, -30degF evaporating intervals, which possibly approximates the operating conditions in this refrigerator. These tabulated values assume the application of a compressor suction HX, but this doesnt alter the COP much.

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