99 ford taurus blows warm air changed the thermostat hoses are getting hot but not hot air circulating in?

the car the heater blower was replaced full job done on it Now i dont know where to begin

Heater core is probably clogged up with crap.You can have it flushed out.

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disconnect the htr hose's from the engine and reverse flush the htr core,with a garden hose with a nozzle. the heater core gets clogged with rust and scale.reverse flushing dislodges alot of that and lets the heated coolant run through it again.
experience
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There is a by-pass hose in line with the heater core that allows the hot coolant to basically allows the hot coolant to do just that 'bypass the heater core. Cut the line and install a blockage in that line and you will have good heat again. I have done this to many vehicles and it works perfectly with no ill affects on the engine.
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