Help: Lack of heat Options

[azian_advanced]

hey guys.. i'm trying to figure out why i don't get much heat from the heater. i'd say i'm getting half the heat than what i should be getting.

i recently replaced my thermostat and radiator cap and flushed my radiator fluid and have no leaks whatsoever inside or out.

when i warm up the car, the upper radiator hose gets hot and the lower one is sort of warm (like it should).

but the heater hoses are barely warm. i've bled the system for any air locks also. my guess is there is a clog somewhere along the heater core lines or perhaps the heater core is defective/corroded. i really hope it isn't cuz it costs $400 or more from the dealer.

what do you think the problem might be? any help would be greatly appreciated.