Looking at the Fan Power ACP, it seems to be set to run the A/C at very high head pressures. R134a refrigerant typically runs at around the 700 to 900 kpa range in normal air conditioning applications however the standard PCM settings look to run this pressure much higher, probably around the 1500 kpa mark.
Running at this pressure means more engine power is required to run the compressor and also impacts on A/C cooling efficiency.
Are there other reasons why these setting are so high? The only thing I can think of is that bringing the fans on earlier for the the sake of A/C effiency might cause the engine to run too cool. Any thoughts on this one?