The 45degree angle is correct, that is not the problem. Even if the coil looks clean it can have a film of oil that causes the water to sheet down, not adhere to the coil and drip off. NEVER use a teflon product on an evaporator coil, it will make the problem worse. Do not use condenser coil cleaner or anything caustic for the same reason. The best thing to use is Electrasol dish washing detergent in the powedered form. Mix one cup to a gallon of hot water and spray on. Let it set and then rinse it off with hot water. Allow the coil to dry before putting back into operation. The coil has to form a slight oxidation in order for the water to adhere and drain properly. Allowing it to dry ( get air onto the coil surface) will let it oxidize. This should take care of your problem. If not, contact the Carrier distributor service manager and ask about Chem Arrow. It is a special chemical that should take care of this if used correctly. It is expensive and requires a special sprayer, but if all else fails it will do the job.
If all else fails....Try reading the directions!
Tell it like it is and let the chips fall where they may.
Any views or opinions stated here are strictly my own.