Does the receiver/dryer have a finite life? ie it can only absorb a certain amount of moisture? (filled with silica gell as far as i can establish..)
Can it be 'rejuvenated' by baking for example, to drive off accumulated moisture?
I'm thinking if the system has been empty of gas for a while, or the dryer has been off the car for a while, then it may have to be replaced?

Any help or info appreciated!

Cheers
Rich