small version of microprocessor is micro controller and this is enough for controlling air conditioning system and probably cost is reduced when we use micro controller cheers
To start with, using a microprocessor will increase the cost by adding more components to the BOM. The microcontrollers today are mature enough to use in almost all of the standalone system needs. you do not normally need to care about your timing (in memory access) clock speed and many such things using a low power internally clocked microcontrollers. You can get instant o/p after writing a couple lines of C and you can easily test it with a PC.
Guess you are talking about 10-15 years old airconditioners. Instead microprocessors, today almost every split or window AC's are controlled by microcontrollers and thus are more energy efficient and more intelligent than thier ancestors. Too we have the ease of controlling these by remotes which is too controlled by a micro.
Cheers
maybe he wanted some advise at setting an active electronic device based on microprocessors/microcontrollers, over a very 'harsh' environment (temperature changes, dust and air/water flow...)