I have a Ford 2002 Windstar with no heat? The blower motors (front/back) are working and the AC works. So what could it be?
Is your radiator coolant coming up to correct temperature? A thermostat stuck open would prevent proper heating.
If the coolant warms up properly I would suspect the blend door or its controlling mechanism. The door might be stuck in the Off position.
Have you checked the coolant level?
A common problem is the blend door motors but front and back together seems unlikely.
I Would First Follow Tester’s Advice And Check The Coolant Level
Do you regularly check the coolant level? Really low coolant volume can result in your getting no heat and at the same time cause the engine to get too hot, which is not good.
Should this be the case and adding coolant doesn’t correct the condition, then you might have to have the air purged from the cooling system. The coolant level will have to be closely monitored for a while. A continually dropping level could indicate an external or internal leak.