2002 Volvo S60 Passenger side blows hot air . . .

Overall air conditioning performance dropped over the season - went from freezing me out to kind of cool and/or nothing. Took to the dealer, said they found a leak and replaced the coolant for $300. A/C still not working especially, if the temperature is above 70 degrees. Dealer said they tested it and it was fine (I'm thinking they tested in the morning when it was cooer outside). Passenger side blows hot air intermittantly. Driver's side blows fairly cold, but needs to be turned on Max for it have any effect. On days above 85, it's almost useless and just never gets cool in the car. Anyone sitting on the passneger side melts because they get heat half the time.