What a great site. I'm a new homeowner, hence I am new to the HVAC world.

I live in a ~ 1,500SF one floor house that has a "Comfortmaker" air conditioner and a Comfortmaker airhandler (in the attic). The house was built in 1996 and I purchased it last year.

The air conditioning has always been really weak to me. I don't feel like the air is cold enough from the vents, and plus I think the airflow is terrible. The air handler is in the attic right above the master bedroom, and the airflow is just OK. However, the airflow is extremely weak througout the rest of the house. I have 10 ft ceilings and the only way to feel air from the vents is to put your hand right below the vents. I assume part of this problem is because there are no dampers in our ductwork (confirmed by the HVAC installer). However, even if I had dampers installed, I still feel like the airflow will be weak. I change my air filters religiously, and always make sure the outside air condition is free of debris. Am I missing something that might be hampering the air flow?

Second , if the temperature outside of the house is 95 degrees, the house will never cool below 78 degrees even though the air conditioner runs constantly. For instance, the unit ran for 15 hours on Friday in 95 degree weather and never cooled the below 78 degrees. Could this be a refrigerant issue?

I need some expert advice. I don't know if this is normal or if Comfortmaker is a horrible brand. I have heard it is the builder brand and therefore might be really cheap. I don't know the tonnage is of hand, but I can check if need be.

I greatly appreciate your help! I feel clueless when it comes to HVAC.