I have had this cool-n-save thing on my AC compressor for couple years, but never figured out how much it actually helped. Until today... I just got an idea to measure the current the compressor consumes. I have an clamp on current meter that I can easily clamp on the wires.
Today it was hot day in Texas, about 99F, and I fired up the AC. (Believe it or not... I really do not use our central AC much... I use mostly window AC units on the rooms we reside) At first without Cool-n-save operating the current consumption was ~18.3A. When I turned the cool-n-save on the current dropped to ~17.4A. This is on a 3.5 ton Carrier brand compressor from 2001.
Calculating back you can see about 5% reduction in power consumption. This is on the compressor only, but I do not think the compressor does "work more" BTU's. Does it? The reason for my thinking is that it is a piston based compressor and always compress the same amount of gas to condenser coil... and the RPM stays the same due to motor locked to 60Hz. (But I could be wrong... I'm not AC expert.)
It really seem to help more if the water is sprayed to the coils and evaporates there, rather than in air. But as most you know the buildup of deposit is rather serious problem. It is not easy to wash out. I have tried to use CLR but it can remove some of it, not all. (At least when not tried intensive brushing...)
I think the same or better effect would be achieved with geothermal system where the compressor condenser would be cooled with earth cool water. This is more expensive system but in the long run should pay itself back. It could also be used as heat pump during winter.
By the way, my first post here!
