Hello and good day Neil:
There could be a few factors, and one is the Heater control unit.
Does the Fan work??
It's probably just a blend door not opening.
Originally Posted by Neill 442
I have a 2000 Taurus SES 3.0L automatic at the end of winter last year the heat was poor and has not gotten any better. So far I have replace the thermostat,Flushed the cooling system inclueding removing the hoses at the heater core to flush it and today replaced the water pump. I still have no heat is there something I'm missing, could the heater control unit need calibrating? Thanks for any and all help.
Ford stopped using a valve to control the water into the heater core to control the heater temperature. Instead they use a “blend door” to mix hot and cold air to achieve desired temperature. That’s why you only get fresh (outside) air on the heat settings. The blend door controls the flow of air through and around the heater core. Two things could have gone wrong:
1. The electric actuator (motor) that moves the door is bad.
2. The hinge attached to the actuator is broken.
If it is the blend door pray it’s #1. A broken door means opening the evaporator housing to replace the door itself. That requires discharging the AC system to remove the housing. I’ve read where guys have dissected the evap housing to repair the door with out removal.