heat doesnt work ,fan blows but heat doesnt come out . on 2002 Infiniti Q45

i replaced controll head , thermostat ,and flushed cooling system .

Asked by for the 2002 Infiniti Q45
do you mean no air flow or just cold air??

just cold air
check the temp of the inlet and out of the heater core. they should be around 170 in and 150 out. if not, the heater core may be clogged