Conversion for Discontinued Compressors
Conversion for Discontinued Compressors
(OP)
I have a job that is using a SABROE SMC3-65 compressor, 6510 kcal/hr at 1700 rpm. This compressor was discontinued about 20 years ago, and I am looking for a replacement. The compressor feeds five evaporator coils in a refrigeration system from freezer to dry stores. I calculate (from the cylinder diameter and stroke) that the volume moved of R-22 is just under 10 cubic ft/min. Assuming I did the calculation right, what conversion is needed to go from ft3/min to lbs/hr?





RE: Conversion for Discontinued Compressors
The equation looks like
#/hr = (60 ft^3/min)*(p #/ft^3)
The problem is what density do you use for the R22 since the temperature, pressure, and phase of the R22 vary throughout the process. I would suggest starting with the actual density at the suction side of the compressor.
One thought - did you consider the volumetric efficiency in your calculation?
Regards
Dave
RE: Conversion for Discontinued Compressors
If you are going to change the compressor, consider changing to something other than R-22 now as well.
10 CFM is pretty run-of-mill. You should have no problems finding a comparable flow compressor from any number of manufacturers.
RE: Conversion for Discontinued Compressors
If you are running the compressor at 0*F evaporator and a saturated liquid temperature of 90*F then you have a refrigerant flow of ~ 3# R-22/min/ton and at 100*F (SLT) it would be about 3.15#/min/ton. If you are interested in using a different refrigerant then I suggest you read this:
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