No heat in ND

[cwilkie]

I have a question guys. My heat does not blow very strong when the fan is on high. When I move the heat slider to shut the heat door the fan blows strong but with cold air. With the fan still on high when I move the slider to turn the heat on it blows weak. It does not matter if the air blows out of the top vents or floor. This is a no. AC cab. It has a new heater core and the fan is in deed blowing air.

I know I need to take the heater box apart tomorrow but I reall do not know what to look for.
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