to reduce the temperature of the HVAC evaporator coil, remove freon
I recently met an oldtimer that claimed to reduce the temperature of the HVAC evaporator coil, all one had to do was remove freon until the temperature dropped. When one removes freon, the capacity of the system is reduced. If one reduced enough freon to cause the coil to drop 40 degrees, one would probably reduce the capacity by 40-60%. The system may run cooler, but the capacity would not be enough on a hot day. The motor will exhibit a lower amp draw, but the net loss would affect cooling.