Rooftop Air-conditioner dripping then pouring water...help

my wife is a mobile dog groomer with a Dodge Sprinter van. When her roof air-conditioner leaks, the first thing I do is check her air filter, then I remove the AC cover on the roof, remove the evaporator cover and blow out the evaporator.it is always clogged and wet with condensate. While I’m on the roof with the cover off I clean the condensate drip holes. I need to do this twice a year with all the dog hair flying around. Hope this helps