Caflashbob - In my experience as an automotive engineer, for a couple years (sort of as a side project) I did A/C system audits. We rarely found any issues at the plant. It is a robust method used in an auto plant to build the A/C system and charge it. Very effective. However, during the course of that study, it was made clear to me that 90% (or more) of the problems with an air conditioning system are due to a leak of refrigerant. The symptom may not necessarily be a direct result of low refrigerant, but the root cause is invariably (90% of the time or greater) due to a refrigerant leak.

So, if you're having slow cooling, I suggest to recharge the system in a way of your choosing. Consider adding refrigerant with stop leak in it, but if you're going to do it yourself, you must follow the directions on the can if it has stop leak in it.

 

 

Instead of increasing the fan speed. Try lowering the set temp lower, just to see what happens. If it's as low as it goes already, then the fan should have sped up by itself.

 

Refrigerant leak issue is not only on automotive system. It's every where; residential, industrial systems as well. One sure sign of refrigerant level being too low is ice build up on evaporator.

 

Htony - I believe you. It's amazing how well a car's A/C system works, and for how long it works, seeing the beating cars take traveling the roads. Those systems you mention are static.