In our earlier post we noted immediate performance gains as IceCOLD was installed of 7% reduction in compressor power and a 24% reduction in compressor running times. We promised additional results as the testing was completed.
For this part of the data analysis, we used a statistical method called a "scatter diagram." With this, the entire test data set of over 13,000 individual data points was placed into two pools, one before and one after the installation. Each of these data pools was independently charted with compressor / condenser amps and outdoor temperatures. These are presented here:
Both graphs use linear regression analysis on the plot of data gathered. The first gives us a formula: Amps
= 0.029 Temp + 4.0567. The slope of the line (.029 in the pre-test) is the rate of increase in compressor Amps per degree Fahrenheit. The R
2 value is a measure of confidence, the "regularity or dependability" of the data.
The second graph is data immediately following the installation of IceCOLD. The data shows a different lower slope of 0.0225. This is a "flatter" graph indicating lower power consumption at all temperatures.
This represents a 9% reduction in condensing unit power per minute at the temperatures present during the period. The IceCOLD did not reduce cycle lengths below 50 degrees outside. We expected this effect. The absence of "flooded condenser control" in the condensing unit means that normal unit capacity is reduced during cool weather. Above 50 degrees, the impact of the product was pronounced. At 70 degrees outdoors, the compressor cycle length was cut by and average of 17%. At 80 and above, the reduction was above 20%.
The important result is that the initial results were verified in a full-length test. The noticeably quieter compressor operation continued from the moment of installation to the full length of the testing. The initial finding of a overall power saving of 30% was confirmed for the full test period and at all temperatures available during the testing.
No comments:
Post a Comment