AC appears to work when driving, although inside car temp feels

Question: AC appears to work when driving, although inside car temp feels like its on the increase. When stopped temperture guage increases from mid point to near full deflection, continued driving drives the temp sensor back towards mid point, although not much cooling going on. Clutch like sound from compressor kicking on and off, when observed flywheel appears to start and stop, large AC fan (top of cooling housing) does not kick in at any point, although it sounds like there is a demand for it. Complete cooling housing replaced appx 12-18 months ago...car odometer only 50000km operating in Saudi Arabia, extreem ambient temperature...any suggestions Answer: The compressor clicking on and off is a sure cut sign of the system being low on freon. Once the freon level is full then the system will work properly. Reference Link: Air Conditioning Troubleshooting