no heat coming from vents sitting still. only heat at 35+mph?

[jimj]

2006 Dodge Minivan. No heat while vehicle is sitting still. athe only way to get heat is to go 35 + mph then there is all the heat you want.

 

[josephrob2003]

a few things to check out
make sure the water level is topped up, with no air locks.
heat exchange valve is fully opening
and finally your thermostat is not sticking open,it should stay closed until the engine reaches normal working temperature.
is your fan working?

 

[Ryan]

Thermostat is stuck open