Dual Zone heater Blower works

Engine warm and NO heat then after a few minutes it may Blow Heat.

It never did this before.

Any Ideas?

Help!

 

one of three things might be wrong
1. thermostat getting stuck open
2. the dual controlls are worn out not letting the baffels open
3. the actuators that open the heater baffels is needing to be fixed
i would go with the first one replace the thermostat and do a flush and see if that works. then would move to the second the dual heater controlls. then all else fales have the heating system checked as in the aculators that swaps from the heater cor and the a/c condenser. it is usually one of the first two. i will also recomend checking the fuses as well when you do the thermo swap out. to make sure every thing is getting power when you are there under the hood