Central A/C in attic problem

[Luvsoutdoors]

Our house has radiant heat(electric)in the ceiling. The AC is ducted to the rooms thru attic. The blower/fan is in the attic-about in the middle of house. There is a 18"x18" grate/opening in hallway for access. About 4 times in the 10 years we have had it, this grate area drips water on the first warm day after the cold winter. There is a styrofoam box built with an opening to get to the filter,above the grate. We insulate the opening in the fall with batt and tape everything shut. Its just been a couple of water spots before but this year its like a dinner plate. Ideas, solutions welcome

[youngie22]

drain plug may be clogged, alot if times the make it drip where it is visible so no major problems occur. Pretty sure the is either a drain issue or some sort of condensation issue. Does your air handler in the attic have a "leak tray" below it or just sitting in the rafters

[King Canada]

Frost buildup that finally melted. See it a lot on exhaust fans.

[Luvsoutdoors]

How do you prevent the frost in the first place? One guy said don't insulate box & grate-just let the warm air go upin the attic. Wouldn't that be worse -we'd get more condensation over entire attic, esp since heat rises and we have a panel within 4 feet of it. Another said insulate the box more. The one that put it in is no longer in business so who is right??

[youngie22]

I don't think it is possible to "overinsulate". I would think that if it is condensation thawing from winter. insulation and ventilation are your only solutions, I may be wrong on that one