Patent ID: 8682527

Claim:
A method of operating an air conditioning system having a compressor and an evaporator that are operably connected, the method comprising: changing output of the compressor based on a temperature limit of the evaporator, the temperature limit being one of a predetermined fixed temperature limit and a variable temperature limit; and determining the variable temperature limit by: determining a target air outlet temperature for conditioned air in a control space, detecting an actual evaporator temperature, calculating a difference between the target air outlet temperature and the actual evaporator temperature, finding a predetermined first temperature adjustment that correlates to the difference, finding a predetermined second temperature adjustment that correlates to another condition; calculating the variable temperature limit by adjusting the fixed temperature limit by one of the first and second temperature adjustments, and determining if an engine temperature is below a predetermined limit, and wherein changing output of the compressor includes changing output of the compressor based on predetermined fixed temperature limit instead of the variable temperature limit when the engine temperature is below the predetermined limit.